1 Introduction of Digital Watermarking

11 Introduction

The popularity of World Wide Web demonstrated the commercial potential of offering multimedia resources through the digital networks Since commercial interests seek to use the digital network to offer digital media for profit they have a strong interest in protecting their ownership rights The digital data can be processed accessed and it can be transmitted very quickly using networks There are numerous technical legal and organisational problems which arise when there is wide scale use of digital documents

Digital information can be copied any number of times from one medium to another they can be transmitted through networks etc all without compromising the quality of the data There is no way to distinguish between an original electronic documents and its copy It is easy to change any part of an un protected electronic document One possibility here is to replace original signatures with cryptographic methods Digital signature is data items formed by the signatory and created from the document that is to be signed

It relates the documents to the signatory in a secure and reliable way The signature of one document cannot be used to sign another even if the two documents in question differ by just a single character Digital watermarking has been proposed as one way to accomplish this

Also advanced Internet services enabled the users to create copy and distribute multimedia products such as audio video and still images with much ease and less effort minimum or no cost and in less time

Though it encouraged trading on the Internet but on the other hand it has created the problem of illegal copying or copyright infringement E-commerce has become a significant business with well-established online shopping services and online delivery of digital media such as audio and video Thus protection of digit alrights assumed a primary importance in the digital age

12 History of Watermarking

Although paper was invented in China over a thousand years ago the Europeans only began to manufacture it in the 11th and 12th centuries after Muslims had established the first paper mills in Spain Soon after its invention Chinese merchants and missionaries transmitted paper and knowledge of papermaking to neighboring lands such as Japan Korea and Central Asia It was there that Muslims first encountered it in the 8th century Islamic civilization spread knowledge of paper and papermaking to Iraq Syria Egypt North Africa andfinally Spain Most accounts of the history of paper focus either on its Origins in China or its development in Europe and simply disregard the centuries when knowledge of paper and papermaking spread throughout the Islamic lands Some of this neglect is due to the difficulty of

Page | 1

studying Islamic paper since Islamic papers unlike later European papers do not have watermarks and are consequently very difficult to localize and date This explains why the oldest watermarked paper found in archives dates back to 1292 in Fabriano Italy The marks were made by adding thin wire patterns to the paper molds The paper would be slightly thinner where the wire was and hence more transparent At the end of 13th century about 40 paper mills were sharing the paper market in Fabriano and producing paper with different format quality and price Competition was very high and it was difficult for any party to keep track of paper provenance and thus format and quality identification The introduction of watermarks was the best method to eliminate any possibility of confusion The digitization of todayrsquos world has expanded the watermarking concept to include digital approaches for use in authenticatingownership claims and protecting proprietary interests

13 Overview of Digital Watermarking

Information hiding (or data hiding) is a general term encircling a wide range of problems beyond the embedding messages in content The term hiding can refer to either for information imperceptibility (watermarking) or information secrecy (steganography) Watermarking and steganography are two important sub disciplines of information hiding that are closely related to each other and may be coincide but with different underlying properties requirements and designs thus result in different technical solutions Steganography is a term derived from the Greek words steganos which means ldquocoveredrdquo and graphia which means ldquowritingrdquo It is the art of concealed communication The existence of a message is secret

Examples include invisible ink which would glow over a flame used by both the British and Americans to communicate secretly during the American Revolution and hidden text using invisible ink to print small dots above or below letters and by changing the heights of letter-strokes in texts used by German spies in World Wars Watermarking which a term used back from paper watermarking on the other hand has the additional concept of resilience against attempts to remove the hidden data This is because the information hidden by watermarking systems isalways associated to the digital object to be protected or its owner while stenographic systems just hide any information Robustness criteria are also different since steganography mainly concerns with detection of hidden message while watermarking concerns potential removal by a pirate Besides steganography typically relates to covert point-to-point communication while watermarking is usually one-to-many

14 Definition of Digital Watermarking

Digital watermarking can be defined as the process of embedding embedding a certain piece of information (technically known as watermark) into multimedia content including text documents images audio or video streams such that the watermark can be detected or extracted later to make an assertion about the data A generalized watermark model consists of watermark encoding and detection processes as shown in Fig 1 and Fig 2 The inputs to the embedding process are the watermark the cover object and a secret key The key is used to enforce security and to protect the watermark The output of the watermarking scheme is the

Page | 2

watermarked data The channel for the watermarked data could be a lossy noisy unreliable channel Thus the received data may be different from the original watermarked data The inputs for extraction are the received watermarked data and the key corresponding to the embedding key The output of the watermark recovery process is the recovered watermark

Fig 1 Watermark embedding

Fig 2 Watermark detection

Page | 3

Water mark embedding process

Page | 4

Page | 5

Page | 6

2 Purpose of Digital Watermarking Watermarks added to digital content serve a variety of purposes The following list details six purposes of digital watermarking

Fig 7 Pupose of digital watermarking

Identify a misappropriating person Trace the marked documentrsquos dissemination through the network to avoid unauthorized duplication and distribution of publicly available multimedia

content added to limit the number of copies created whereas the watermarks are modified by the

hardware and at some point would not create any more copies content stamped with a visible watermark that is very difficult to remove so that it can be

publicly and freely distributed Prove ownership

Page | 7

21 Examples of watermarking

Reporting or recording certain information about how the watermarked media is being transmitted accessed or used

EXAMPLE Broadcast monitoring equipment in use today detects watermarks in broadcasts and uses them to generate automatic reports about when where and how often specific content is being aired

EXAMPLE Web crawlers or media player devices could look for watermarks in content they crawl or play and then record information about where and when specific marked files are found or played

Providing information to the individual user

EXAMPLE A media player device upon reading a watermark in a file the user is accessing could display additional information that might interest the user such as metadata (information about the content) a special commercial offer or confirmation that the content is genuine and has not been altered Enabling or disabling access to particular capabilities or content

EXAMPLE An online service upon reading a watermark in content a user is trying to access could provide the user with an updated or authorized version of the content Triggering an investigation complaint or even legal measures concerning a particular user or distributor of watermarked content

EXAMPLE Watermarks embedded in infringing copies of copyrighted media content could enable copyright holders to trace the copies back to particular users or distributors and potentially to launch legal action

Page | 8

3 Requirements of watermarks

To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria

1 The watermark must be difficult or impossible to remove at least without visibly degrading the original image2 The watermark must survive image modifications that are common to typical image-processing applications (eg scaling dithering cropping compression)3 An invisible watermark should be imperceptible so as not to affect the experience of viewing the image and4 For some invisible watermarking applications watermarks should be readily detectable the proper authorities even if imperceptible to the average observer Such decidability without requiring the original un-watermarked image would be necessary for efficient recovery of property and subsequent prosecution

One can understand the challenge of researchers in this field since the above requirements compete each with the others The litmus test of a watermarking method would be that it is accepted and used on a large commercial scale and that it stands up in a court of law None of the digital techniques have yet to meet these tests

Page | 9

4 Properties of digital watermarking techniques

The most important properties of digital watermarking techniques are transparency robustness security capacity invertibility (reversibility) and complexity and possibility of verification Based on these parameters the algorithms can be evaluated if a specific algorithm has adequate properties and can be used for a certain application area

From we define the parameter as follows

Transparency - Relates to the properties of the human sensory A transparent watermark causes no artifacts or quality loss

Robustness - Describes whether the watermark can be reliably detected after media operations It is important to note that robustness does not include attacks on the embedding scheme that are based on the knowledge of the embedding algorithm or on the availability of the detector function Robustness means resistance to ldquoblindrdquo non-targeted modifications or common media operations For example the Stirmark or 2Mosaik tools attack the robustness of watermarking algorithms with geometrical distortions For manipulation recognition the watermark has to be fragile to detect altered media

Security - Describes whether the embedded watermarking information cannot be removed beyond reliable detection by targeted attacks based on a full knowledge of the embedding algorithm and the detector except the key and the knowledge of at least one watermarked data The concept of security includes procedural attacks such as the IBM attack or attacks based on a partial knowledge of the carrier modifications due to message embedding or embedding of templates The security aspect also includes the false positive detection rates

Capacity - Describes how many information bits can be embedded It addresses also the possibility of embedding multiple watermarks in one document in parallel

Invertibility - Describes the possibility to produce the original data during the watermark retrieval

Complexity - Describes the effort and time we need to embed and retrieve a watermark This parameter is essential if we have real time applications Another aspect addresses

Page | 10

whether the original data in the retrieval process or not We need to distinguish between non-blind and blind watermarking schemes

5 Types of Digital Watermarks

Watermarks and watermarking techniques can be divided into various categories in various ways The watermarks can be applied in spatial domain An alternative to spatial domain watermarking is frequency domain watermarking It has been pointed out that the frequency domain methods are more robust than the spatial domain techniques Different types of watermarks are shown in the Figure

Fig 8 Typology of digital watermarking

Watermarking techniques can be divided into two categories according to the type of working domain-

51 Spatial domain

Spatial watermarking can also be applied using color separation In this way the watermark appears in only one of the color bands This renders the watermark visibly subtle such that it is difficult to detect under regular viewing However the mark appears immediately when the colors are separated for printing This renders the document useless for the printer unless the

Page | 11

watermark can be removed from the color band This approach is used commercially for journalists to inspect digital pictures from a photo-stock house before buying unmarked versions

52 Frequency domain

Frequency domain (and other transform domains) by first applying a transform like the Fast Fourier Transform (FFT) In a similar manner to spatial domain watermarking the values of chosen frequencies can be altered from the original Since high frequencies will be lost by compression or scaling the watermark signal is applied to lower frequencies or better yet applied adaptively to frequencies that contain important information of the original picture Since watermarks applied to the frequency domain will be dispersed over the entirety of the spatial image upon inverse transformation this method is not as susceptible to defeat by cropping as the spatial technique However there is more a tradeoff here between invisibility and decodability since the watermark is in effect applied indiscriminately across the spatial image

Watermarking techniques can be divided into four categories according to the type of document to be watermarked as follows

53 Text WatermarkingThe process of embeddinghiding data in text document can be termed as ldquotext watermarkingrdquo This can be use to protect electronic documents paper documents are easy to copy and distribute electronically

54 Image WatermarkingThe process of embeddinghiding data in image document can be termed as ldquoimage watermarkingrdquo This process is done by visible water marking and invisible watermarking

55 Audio WatermarkingThe process of embedding information into audio can be termed as audio watermarking Can be achieved by inserting information about the distributor and the buyer A watermark embedded within an audio stream to identify its origination

56 Video WatermarkingVideo watermarking involves embedding cryptographic information derived from frames of digital video into the video itself Because the watermark is part of the video rather than part of the file format this technology works independently of the video file format or codec

According to the human perception the digital watermarks can be divided into three different types as follows

Page | 12

57 Visible watermark

Visible watermarks are especially useful for conveying an immediate claim of ownership The main advantage is that they virtually eliminate the commercial value of the document to a would-be thief without lessening the documents utility for legitimate authorized purposes A familiar example is in the video domain where a logo is placed in a corner of the screen image

58 Invisible-Robust watermark

The invisible-robust watermark is embedded in such a way that alternations madeto the pixel value are perceptually not noticed and it can be recovered only with appropriate decoding mechanism

59 Invisible-Fragile watermarkThe invisible-fragile watermark is embedded in such a way that any manipulation or modification of the image would alter or destroy the watermark

510 Dual watermark

Dual watermark is a combination of a visible and an invisible watermark In this type of water mark an invisible watermark is used as a backup for the visible watermark as clear from the following diagram

Figure Schematic representation of dual watermarking

From application point of view digital watermark could be as below

511 source based

Source-based watermark are desirable for ownership identification or authentication where a unique watermark identifying the owner is introduced to all the copies of a particular image being distributed A source-based watermark could be used for authentication and to determine whether a received image or other electronic data has been tampered with

Page | 13

512 destination based

The watermark could also be destination based where each distributed copy gets a unique watermark identifying the particular buyer The destination based watermark could be used to trace the buyer in the case of illegal reselling

6 Digital Watermarking Techniques

61 Text-based Watermarking

62 Image Watermarking

63 Audio Watermarking

64 Video Watermarking

61Text-Based Watermarking Techniques

A The text watermarking based on the fine-tuning of document structure

This is a technique which makes the text as a binary image it obtains watermark through fine-tuning the display style and it is imperceptibly by human visual The most classic algorithm is proposed by Brassil and Maxemchuk it gives many different ways to insert watermark in the PostScript document as follows

a) Line-shift encoding for the line space of a text file is uniform the coding method embeds a watermark by vertical shifting an entire line when the movement away from no more than 1 300 inches the human eye cannot easily perceive by analyzing the line spacing can determine whether it contains text watermark the process does not require the participation of the original text

b) word-shift encoding this coding method embeds watermark by level shifting some special words in a line When a word is shifted to right or left itrsquos adjacent words are not moving not moving words are as references location for the process of decoding Experience found that the human eye cannot identify the 1 150 inches below the level of displacement As the document is not a fixed word spacing so to determine whether it contains watermark needs the text of the original documents

c) Characteristics coding the coding method inserts a marker by changing the particular characteristics of a letter such as changing the height of a individual letter fonts etc The above-mentioned three kinds of coding methods are to use the spatial characteristics of text to embed the watermark These algorithm entirely depend on the text format (line-shift word-shift characteristics coding etc) there are many shortcomings such as not enough antiaggressive less robust not well hidden

Page | 14

Fig 9 Text water markingB The text watermark based on the not important content For a text when some of the expressions of the text occur Some minor changes there is no impact for understanding the document for this point the text watermark can be embedded Typical methods include inserting punctuation in sentences or inserting space at the end of a line For example we can store binary information by setting or not setting the comma in the two side-by-side words with and or or to connect

Specifically if the guns butter and flowers expresses the logic 1 then the guns butter and flower is logic0Weakness of such method that is the watermark information may be missing in the transmission process of application In addition the source text can not be arbitrary This method is not currently the main method of text watermarking

C The text watermark based on ldquoreplace the content of textrdquo The method is derived from information hiding technology It looks source text as the significance sequence instead of text images embedded in the course of the text is converted to vector with the same or similar meaning of the text of the secret process So watermark can be embedded by converting the source text into the same or similar meaning of hidden text

Usually in the English text many words have synonyms such as big and 1arge smart and clever and so on so we can elect these specific words of the text constitute a synonym replacement tables The word needs to be replaced said logic 0 the words that do not need to replace the logic 1So the secret data can be hidden in the text the number of hidden data relates to the synonym appear frequency in the text the method also applies to Chinese text The method of synonym replacement hide information by modifying the contents of the text it not only has better robustness but also do not need to rely on a specific document format However this approach requires source text cannot be arbitrary that is should contain a certain number of synonyms have been defined and in the process of extracting information needs the synonyms replace table

D The text watermark Based on natural language processing technology

Natural language processing is to in some specific applications automatically handling the text written in natural language such as machine translation information retrieval information

Page | 15

extraction data mining and intelligent search engines and so on after many years of development of the Natural language processing technology much experience and techniques have been accumulated such as word segmentation syntax analysis restatement eliminate the ambiguity of words and so on These are the foundation of The text watermark Based on natural language processing technology and compared to previous methods through the use of natural language processing technology embedded watermark informationmore secure reliable

Challenges

Marking copies uniquely

Making necessary for a recipient to provide personal information

Using encryption

Uses

Protect electronic documents

Paper documents are easy to copy and distribute electronically

62 Image Watermarking TechniquesIn image watermarking technique different type of technique is used as Digital Image ndash artificial resemblance of original object stored in form of binary numbers Image Watermarking ndash putting in some information that ensures your authentication of the document in the image itself Spatial domain algorithms- Two robust spatial-domain watermarking algorithms for image copyright protection are described as

The first one is robust against compression filtering and cropping Like all published crop-proof algorithms the one proposed here requires the original image for mark recovery Robustness against compression and filtering is obtained by using the JPEG algorithm to decide on mark location and magnitude robustness against cropping is achieved through a repetition code

The second watermarking algorithm uses visual components and is robust against compression filtering scaling and moderate rotations

The Discrete Cosine Transform (DCT)The discrete cosine transform (DCT) helps separate the image into parts (or spectral sub-bands) of differing importance (with respect to the images visual quality) The DCT is similar to the discrete Fourier transform it transforms a signal or image from the spatial domain to the frequency domain

Page | 16

Fig 10 DCT process diagramThe discrete cosine transform (DCT) is a technique for converting a signal into elementary frequency components It is widely used in image compression

Image Histogram

An image histogram is a type of histogram which acts as a graphical representation of the tonal distribution in a digital image It plots the number of pixels for each tonal value By looking at the histogram for a specific image a viewer will be able to judge the entire tonal distribution at a glance63 Audio Watermarking TechniquesIn audio watermarking technique different type of technique is used as

LSB watermarking - Least Significant Bit algorithm that embedding watermark into the least important part of the primary image and the watermark can be extracted from the primary image

The idea behind this watermarking technique is the following if you see you image as a matrix NxM (where N and M are the dimension of the image) you can represent the value of the pixel in the position (ij) as a binary number this binary can be then divided in all of its bit so that you will have a most significant bit (the one that contains quite a lot of information and a least significant bit that contains few information)

Quantisation watermarking - A new method for watermarking based on vector quantisation is proposed It is efficient for implementation with conventional techniques and simulation results show its robustness under a variety of attacks It also represents superiority over existing algorithms

Wavelet transform domain algorithms - The wavelet transform-domain least-mean square (WTDLMS) algorithm is known to have in general a faster convergence rate than the time-domain LMS algorithm and can find many applications in signal processing and communications areas However the computational complexity of the wavelet filter bank is relatively high In this work we show how to exploit the redundancy which exists in the computation of the wavelet coefficients between successive iterations so as to significantly reduce the computational load of the algorithm

Page | 17

7 Applications of Digital Watermarking

There is a wide variety of applications for watermarking The requirements of watermarking systems are always based on the application as for obvious reasons there is no ldquouniversalrdquo watermarking method Although it has to be robust in general different level of required robustness can be identified besides the specific characteristics of the problem which make the watermarking a suitable solution Several applications are listed below

Owner identification ndash similar to copyright protection to establish ownership of the content

Copy protection ndash also known as copy control to prevent people from making illegal copies of copyrighted content

Content authentication ndash to detect modifications of the content as a sign of invalid authentication

Fingerprinting ndash sometimes referred as transaction tracking or traitor tracking to trace back illegal duplication and distribution of the content

Broadcast monitoring ndash specifically for advertisements and in entertainment industries to monitor content being broadcasted as contracted and by the authorized source

Medical applications ndash known as invertible watermarking to provide both authentication and confidentiality in a reversible manner without affecting the medical image in any way

Page | 18

8 Limitations of digital watermarking

In January 1997 a counterfeiting scheme has been demonstrated for a class of invertible feature-based frequency domain invisible watermarking algorithms This counterfeiting scheme could be used to subvert ownership claims because the recovery of the digital signature from a watermarked image requires a comparison with an original The counterfeiting scheme works by first creating a counterfeit watermarked copy from the genuine watermarked copy by effectively inverting the genuine watermark This inversion creates a counterfeit of the original image A comparison of the decoded versions of both yield the owners (authorized) and the forged (inverted) signature This the technique of establishing legitimate ownership recovering the signature watermark by comparing a watermarked image with the original image breaks down It can be shown that both the legitimate signature and counterfeiters signature inhere in both the watermarked and counterfeit watermarked copies Thus while it may be demonstrated that at least one recipient has a counterfeit watermarked copy it cannot be determined which it is

Page | 19

9 Proposed Work

In traditional symmetric watermarking schemes the key used for watermark embedding must be available at the watermark detector This leads to a security problem if the detectors are implemented in consumer devices that are spread all over the world So asymmetric watermarking schemes also named public key digital watermarking schemes attract more and more attentions In such a public key watermarking system the private key is used for watermarking embedding and the public key is used only for watermarking detection The private key is kept for secret and the watermarks cannot easily be removed with public key

We are actually concentrating on studying public key watermarking techniques to evaluate and compare their performance in comparison to private key water marking techniques

Page | 20

10 RESEARCH DIRECTIONS

101 Study on Watermarking Algorithm

Digital watermarking technology processing contains two cores watermark embedding algorithm and detection algorithm Robustness imperceptibility invisibility and security of digital watermarking is generally the focus of the requirements

102 Study on Watermarking Theory

Although there are many published articles on watermarking the current watermarking technology canrsquot yet fill the actual requirements of most users The lack of standards interoperability problems as well as a suit of accurate and realistic requirements to watermarking system is still hinder the development of digital watermarking technology

There are still many problems to be resolved In order to be more widely used digital watermarking should establish a series of standards or agreements such as the standards of watermark embedding detection and certification Different watermarking algorithm has different compatibility and that is obviously not conducive to promoting the application of digital watermarking

103 Study on Watermark Attack

The relationship between watermark attack and watermarking algorithm is the same as spear and shield they restrict each other and promote each other as well To develop the technologies combined with cryptography authentication and digital signature is probably the direction of resistance development to various attacks

Page | 21

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

studying Islamic paper since Islamic papers unlike later European papers do not have watermarks and are consequently very difficult to localize and date This explains why the oldest watermarked paper found in archives dates back to 1292 in Fabriano Italy The marks were made by adding thin wire patterns to the paper molds The paper would be slightly thinner where the wire was and hence more transparent At the end of 13th century about 40 paper mills were sharing the paper market in Fabriano and producing paper with different format quality and price Competition was very high and it was difficult for any party to keep track of paper provenance and thus format and quality identification The introduction of watermarks was the best method to eliminate any possibility of confusion The digitization of todayrsquos world has expanded the watermarking concept to include digital approaches for use in authenticatingownership claims and protecting proprietary interests

13 Overview of Digital Watermarking

Information hiding (or data hiding) is a general term encircling a wide range of problems beyond the embedding messages in content The term hiding can refer to either for information imperceptibility (watermarking) or information secrecy (steganography) Watermarking and steganography are two important sub disciplines of information hiding that are closely related to each other and may be coincide but with different underlying properties requirements and designs thus result in different technical solutions Steganography is a term derived from the Greek words steganos which means ldquocoveredrdquo and graphia which means ldquowritingrdquo It is the art of concealed communication The existence of a message is secret

Examples include invisible ink which would glow over a flame used by both the British and Americans to communicate secretly during the American Revolution and hidden text using invisible ink to print small dots above or below letters and by changing the heights of letter-strokes in texts used by German spies in World Wars Watermarking which a term used back from paper watermarking on the other hand has the additional concept of resilience against attempts to remove the hidden data This is because the information hidden by watermarking systems isalways associated to the digital object to be protected or its owner while stenographic systems just hide any information Robustness criteria are also different since steganography mainly concerns with detection of hidden message while watermarking concerns potential removal by a pirate Besides steganography typically relates to covert point-to-point communication while watermarking is usually one-to-many

14 Definition of Digital Watermarking

Digital watermarking can be defined as the process of embedding embedding a certain piece of information (technically known as watermark) into multimedia content including text documents images audio or video streams such that the watermark can be detected or extracted later to make an assertion about the data A generalized watermark model consists of watermark encoding and detection processes as shown in Fig 1 and Fig 2 The inputs to the embedding process are the watermark the cover object and a secret key The key is used to enforce security and to protect the watermark The output of the watermarking scheme is the

Page | 2

watermarked data The channel for the watermarked data could be a lossy noisy unreliable channel Thus the received data may be different from the original watermarked data The inputs for extraction are the received watermarked data and the key corresponding to the embedding key The output of the watermark recovery process is the recovered watermark

Fig 1 Watermark embedding

Fig 2 Watermark detection

Page | 3

Water mark embedding process

Page | 4

Page | 5

Page | 6

2 Purpose of Digital Watermarking Watermarks added to digital content serve a variety of purposes The following list details six purposes of digital watermarking

Fig 7 Pupose of digital watermarking

Identify a misappropriating person Trace the marked documentrsquos dissemination through the network to avoid unauthorized duplication and distribution of publicly available multimedia

content added to limit the number of copies created whereas the watermarks are modified by the

hardware and at some point would not create any more copies content stamped with a visible watermark that is very difficult to remove so that it can be

publicly and freely distributed Prove ownership

Page | 7

21 Examples of watermarking

Reporting or recording certain information about how the watermarked media is being transmitted accessed or used

EXAMPLE Broadcast monitoring equipment in use today detects watermarks in broadcasts and uses them to generate automatic reports about when where and how often specific content is being aired

EXAMPLE Web crawlers or media player devices could look for watermarks in content they crawl or play and then record information about where and when specific marked files are found or played

Providing information to the individual user

EXAMPLE A media player device upon reading a watermark in a file the user is accessing could display additional information that might interest the user such as metadata (information about the content) a special commercial offer or confirmation that the content is genuine and has not been altered Enabling or disabling access to particular capabilities or content

EXAMPLE An online service upon reading a watermark in content a user is trying to access could provide the user with an updated or authorized version of the content Triggering an investigation complaint or even legal measures concerning a particular user or distributor of watermarked content

EXAMPLE Watermarks embedded in infringing copies of copyrighted media content could enable copyright holders to trace the copies back to particular users or distributors and potentially to launch legal action

Page | 8

3 Requirements of watermarks

To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria

1 The watermark must be difficult or impossible to remove at least without visibly degrading the original image2 The watermark must survive image modifications that are common to typical image-processing applications (eg scaling dithering cropping compression)3 An invisible watermark should be imperceptible so as not to affect the experience of viewing the image and4 For some invisible watermarking applications watermarks should be readily detectable the proper authorities even if imperceptible to the average observer Such decidability without requiring the original un-watermarked image would be necessary for efficient recovery of property and subsequent prosecution

One can understand the challenge of researchers in this field since the above requirements compete each with the others The litmus test of a watermarking method would be that it is accepted and used on a large commercial scale and that it stands up in a court of law None of the digital techniques have yet to meet these tests

Page | 9

4 Properties of digital watermarking techniques

The most important properties of digital watermarking techniques are transparency robustness security capacity invertibility (reversibility) and complexity and possibility of verification Based on these parameters the algorithms can be evaluated if a specific algorithm has adequate properties and can be used for a certain application area

From we define the parameter as follows

Transparency - Relates to the properties of the human sensory A transparent watermark causes no artifacts or quality loss

Robustness - Describes whether the watermark can be reliably detected after media operations It is important to note that robustness does not include attacks on the embedding scheme that are based on the knowledge of the embedding algorithm or on the availability of the detector function Robustness means resistance to ldquoblindrdquo non-targeted modifications or common media operations For example the Stirmark or 2Mosaik tools attack the robustness of watermarking algorithms with geometrical distortions For manipulation recognition the watermark has to be fragile to detect altered media

Security - Describes whether the embedded watermarking information cannot be removed beyond reliable detection by targeted attacks based on a full knowledge of the embedding algorithm and the detector except the key and the knowledge of at least one watermarked data The concept of security includes procedural attacks such as the IBM attack or attacks based on a partial knowledge of the carrier modifications due to message embedding or embedding of templates The security aspect also includes the false positive detection rates

Capacity - Describes how many information bits can be embedded It addresses also the possibility of embedding multiple watermarks in one document in parallel

Invertibility - Describes the possibility to produce the original data during the watermark retrieval

Complexity - Describes the effort and time we need to embed and retrieve a watermark This parameter is essential if we have real time applications Another aspect addresses

Page | 10

whether the original data in the retrieval process or not We need to distinguish between non-blind and blind watermarking schemes

5 Types of Digital Watermarks

Watermarks and watermarking techniques can be divided into various categories in various ways The watermarks can be applied in spatial domain An alternative to spatial domain watermarking is frequency domain watermarking It has been pointed out that the frequency domain methods are more robust than the spatial domain techniques Different types of watermarks are shown in the Figure

Fig 8 Typology of digital watermarking

Watermarking techniques can be divided into two categories according to the type of working domain-

51 Spatial domain

Spatial watermarking can also be applied using color separation In this way the watermark appears in only one of the color bands This renders the watermark visibly subtle such that it is difficult to detect under regular viewing However the mark appears immediately when the colors are separated for printing This renders the document useless for the printer unless the

Page | 11

watermark can be removed from the color band This approach is used commercially for journalists to inspect digital pictures from a photo-stock house before buying unmarked versions

52 Frequency domain

Frequency domain (and other transform domains) by first applying a transform like the Fast Fourier Transform (FFT) In a similar manner to spatial domain watermarking the values of chosen frequencies can be altered from the original Since high frequencies will be lost by compression or scaling the watermark signal is applied to lower frequencies or better yet applied adaptively to frequencies that contain important information of the original picture Since watermarks applied to the frequency domain will be dispersed over the entirety of the spatial image upon inverse transformation this method is not as susceptible to defeat by cropping as the spatial technique However there is more a tradeoff here between invisibility and decodability since the watermark is in effect applied indiscriminately across the spatial image

Watermarking techniques can be divided into four categories according to the type of document to be watermarked as follows

53 Text WatermarkingThe process of embeddinghiding data in text document can be termed as ldquotext watermarkingrdquo This can be use to protect electronic documents paper documents are easy to copy and distribute electronically

54 Image WatermarkingThe process of embeddinghiding data in image document can be termed as ldquoimage watermarkingrdquo This process is done by visible water marking and invisible watermarking

55 Audio WatermarkingThe process of embedding information into audio can be termed as audio watermarking Can be achieved by inserting information about the distributor and the buyer A watermark embedded within an audio stream to identify its origination

56 Video WatermarkingVideo watermarking involves embedding cryptographic information derived from frames of digital video into the video itself Because the watermark is part of the video rather than part of the file format this technology works independently of the video file format or codec

According to the human perception the digital watermarks can be divided into three different types as follows

Page | 12

57 Visible watermark

Visible watermarks are especially useful for conveying an immediate claim of ownership The main advantage is that they virtually eliminate the commercial value of the document to a would-be thief without lessening the documents utility for legitimate authorized purposes A familiar example is in the video domain where a logo is placed in a corner of the screen image

58 Invisible-Robust watermark

The invisible-robust watermark is embedded in such a way that alternations madeto the pixel value are perceptually not noticed and it can be recovered only with appropriate decoding mechanism

59 Invisible-Fragile watermarkThe invisible-fragile watermark is embedded in such a way that any manipulation or modification of the image would alter or destroy the watermark

510 Dual watermark

Dual watermark is a combination of a visible and an invisible watermark In this type of water mark an invisible watermark is used as a backup for the visible watermark as clear from the following diagram

Figure Schematic representation of dual watermarking

From application point of view digital watermark could be as below

511 source based

Source-based watermark are desirable for ownership identification or authentication where a unique watermark identifying the owner is introduced to all the copies of a particular image being distributed A source-based watermark could be used for authentication and to determine whether a received image or other electronic data has been tampered with

Page | 13

512 destination based

The watermark could also be destination based where each distributed copy gets a unique watermark identifying the particular buyer The destination based watermark could be used to trace the buyer in the case of illegal reselling

6 Digital Watermarking Techniques

61 Text-based Watermarking

62 Image Watermarking

63 Audio Watermarking

64 Video Watermarking

61Text-Based Watermarking Techniques

A The text watermarking based on the fine-tuning of document structure

This is a technique which makes the text as a binary image it obtains watermark through fine-tuning the display style and it is imperceptibly by human visual The most classic algorithm is proposed by Brassil and Maxemchuk it gives many different ways to insert watermark in the PostScript document as follows

a) Line-shift encoding for the line space of a text file is uniform the coding method embeds a watermark by vertical shifting an entire line when the movement away from no more than 1 300 inches the human eye cannot easily perceive by analyzing the line spacing can determine whether it contains text watermark the process does not require the participation of the original text

b) word-shift encoding this coding method embeds watermark by level shifting some special words in a line When a word is shifted to right or left itrsquos adjacent words are not moving not moving words are as references location for the process of decoding Experience found that the human eye cannot identify the 1 150 inches below the level of displacement As the document is not a fixed word spacing so to determine whether it contains watermark needs the text of the original documents

c) Characteristics coding the coding method inserts a marker by changing the particular characteristics of a letter such as changing the height of a individual letter fonts etc The above-mentioned three kinds of coding methods are to use the spatial characteristics of text to embed the watermark These algorithm entirely depend on the text format (line-shift word-shift characteristics coding etc) there are many shortcomings such as not enough antiaggressive less robust not well hidden

Page | 14

Fig 9 Text water markingB The text watermark based on the not important content For a text when some of the expressions of the text occur Some minor changes there is no impact for understanding the document for this point the text watermark can be embedded Typical methods include inserting punctuation in sentences or inserting space at the end of a line For example we can store binary information by setting or not setting the comma in the two side-by-side words with and or or to connect

Specifically if the guns butter and flowers expresses the logic 1 then the guns butter and flower is logic0Weakness of such method that is the watermark information may be missing in the transmission process of application In addition the source text can not be arbitrary This method is not currently the main method of text watermarking

C The text watermark based on ldquoreplace the content of textrdquo The method is derived from information hiding technology It looks source text as the significance sequence instead of text images embedded in the course of the text is converted to vector with the same or similar meaning of the text of the secret process So watermark can be embedded by converting the source text into the same or similar meaning of hidden text

Usually in the English text many words have synonyms such as big and 1arge smart and clever and so on so we can elect these specific words of the text constitute a synonym replacement tables The word needs to be replaced said logic 0 the words that do not need to replace the logic 1So the secret data can be hidden in the text the number of hidden data relates to the synonym appear frequency in the text the method also applies to Chinese text The method of synonym replacement hide information by modifying the contents of the text it not only has better robustness but also do not need to rely on a specific document format However this approach requires source text cannot be arbitrary that is should contain a certain number of synonyms have been defined and in the process of extracting information needs the synonyms replace table

D The text watermark Based on natural language processing technology

Natural language processing is to in some specific applications automatically handling the text written in natural language such as machine translation information retrieval information

Page | 15

extraction data mining and intelligent search engines and so on after many years of development of the Natural language processing technology much experience and techniques have been accumulated such as word segmentation syntax analysis restatement eliminate the ambiguity of words and so on These are the foundation of The text watermark Based on natural language processing technology and compared to previous methods through the use of natural language processing technology embedded watermark informationmore secure reliable

Challenges

Marking copies uniquely

Making necessary for a recipient to provide personal information

Using encryption

Uses

Protect electronic documents

Paper documents are easy to copy and distribute electronically

62 Image Watermarking TechniquesIn image watermarking technique different type of technique is used as Digital Image ndash artificial resemblance of original object stored in form of binary numbers Image Watermarking ndash putting in some information that ensures your authentication of the document in the image itself Spatial domain algorithms- Two robust spatial-domain watermarking algorithms for image copyright protection are described as

The first one is robust against compression filtering and cropping Like all published crop-proof algorithms the one proposed here requires the original image for mark recovery Robustness against compression and filtering is obtained by using the JPEG algorithm to decide on mark location and magnitude robustness against cropping is achieved through a repetition code

The second watermarking algorithm uses visual components and is robust against compression filtering scaling and moderate rotations

The Discrete Cosine Transform (DCT)The discrete cosine transform (DCT) helps separate the image into parts (or spectral sub-bands) of differing importance (with respect to the images visual quality) The DCT is similar to the discrete Fourier transform it transforms a signal or image from the spatial domain to the frequency domain

Page | 16

Fig 10 DCT process diagramThe discrete cosine transform (DCT) is a technique for converting a signal into elementary frequency components It is widely used in image compression

Image Histogram

An image histogram is a type of histogram which acts as a graphical representation of the tonal distribution in a digital image It plots the number of pixels for each tonal value By looking at the histogram for a specific image a viewer will be able to judge the entire tonal distribution at a glance63 Audio Watermarking TechniquesIn audio watermarking technique different type of technique is used as

LSB watermarking - Least Significant Bit algorithm that embedding watermark into the least important part of the primary image and the watermark can be extracted from the primary image

The idea behind this watermarking technique is the following if you see you image as a matrix NxM (where N and M are the dimension of the image) you can represent the value of the pixel in the position (ij) as a binary number this binary can be then divided in all of its bit so that you will have a most significant bit (the one that contains quite a lot of information and a least significant bit that contains few information)

Quantisation watermarking - A new method for watermarking based on vector quantisation is proposed It is efficient for implementation with conventional techniques and simulation results show its robustness under a variety of attacks It also represents superiority over existing algorithms

Wavelet transform domain algorithms - The wavelet transform-domain least-mean square (WTDLMS) algorithm is known to have in general a faster convergence rate than the time-domain LMS algorithm and can find many applications in signal processing and communications areas However the computational complexity of the wavelet filter bank is relatively high In this work we show how to exploit the redundancy which exists in the computation of the wavelet coefficients between successive iterations so as to significantly reduce the computational load of the algorithm

Page | 17

7 Applications of Digital Watermarking

There is a wide variety of applications for watermarking The requirements of watermarking systems are always based on the application as for obvious reasons there is no ldquouniversalrdquo watermarking method Although it has to be robust in general different level of required robustness can be identified besides the specific characteristics of the problem which make the watermarking a suitable solution Several applications are listed below

Owner identification ndash similar to copyright protection to establish ownership of the content

Copy protection ndash also known as copy control to prevent people from making illegal copies of copyrighted content

Content authentication ndash to detect modifications of the content as a sign of invalid authentication

Fingerprinting ndash sometimes referred as transaction tracking or traitor tracking to trace back illegal duplication and distribution of the content

Broadcast monitoring ndash specifically for advertisements and in entertainment industries to monitor content being broadcasted as contracted and by the authorized source

Medical applications ndash known as invertible watermarking to provide both authentication and confidentiality in a reversible manner without affecting the medical image in any way

Page | 18

8 Limitations of digital watermarking

In January 1997 a counterfeiting scheme has been demonstrated for a class of invertible feature-based frequency domain invisible watermarking algorithms This counterfeiting scheme could be used to subvert ownership claims because the recovery of the digital signature from a watermarked image requires a comparison with an original The counterfeiting scheme works by first creating a counterfeit watermarked copy from the genuine watermarked copy by effectively inverting the genuine watermark This inversion creates a counterfeit of the original image A comparison of the decoded versions of both yield the owners (authorized) and the forged (inverted) signature This the technique of establishing legitimate ownership recovering the signature watermark by comparing a watermarked image with the original image breaks down It can be shown that both the legitimate signature and counterfeiters signature inhere in both the watermarked and counterfeit watermarked copies Thus while it may be demonstrated that at least one recipient has a counterfeit watermarked copy it cannot be determined which it is

Page | 19

9 Proposed Work

In traditional symmetric watermarking schemes the key used for watermark embedding must be available at the watermark detector This leads to a security problem if the detectors are implemented in consumer devices that are spread all over the world So asymmetric watermarking schemes also named public key digital watermarking schemes attract more and more attentions In such a public key watermarking system the private key is used for watermarking embedding and the public key is used only for watermarking detection The private key is kept for secret and the watermarks cannot easily be removed with public key

We are actually concentrating on studying public key watermarking techniques to evaluate and compare their performance in comparison to private key water marking techniques

Page | 20

10 RESEARCH DIRECTIONS

101 Study on Watermarking Algorithm

Digital watermarking technology processing contains two cores watermark embedding algorithm and detection algorithm Robustness imperceptibility invisibility and security of digital watermarking is generally the focus of the requirements

102 Study on Watermarking Theory

Although there are many published articles on watermarking the current watermarking technology canrsquot yet fill the actual requirements of most users The lack of standards interoperability problems as well as a suit of accurate and realistic requirements to watermarking system is still hinder the development of digital watermarking technology

There are still many problems to be resolved In order to be more widely used digital watermarking should establish a series of standards or agreements such as the standards of watermark embedding detection and certification Different watermarking algorithm has different compatibility and that is obviously not conducive to promoting the application of digital watermarking

103 Study on Watermark Attack

The relationship between watermark attack and watermarking algorithm is the same as spear and shield they restrict each other and promote each other as well To develop the technologies combined with cryptography authentication and digital signature is probably the direction of resistance development to various attacks

Page | 21

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

watermarked data The channel for the watermarked data could be a lossy noisy unreliable channel Thus the received data may be different from the original watermarked data The inputs for extraction are the received watermarked data and the key corresponding to the embedding key The output of the watermark recovery process is the recovered watermark

Fig 1 Watermark embedding

Fig 2 Watermark detection

Page | 3

Water mark embedding process

Page | 4

Page | 5

Page | 6

2 Purpose of Digital Watermarking Watermarks added to digital content serve a variety of purposes The following list details six purposes of digital watermarking

Fig 7 Pupose of digital watermarking

Identify a misappropriating person Trace the marked documentrsquos dissemination through the network to avoid unauthorized duplication and distribution of publicly available multimedia

content added to limit the number of copies created whereas the watermarks are modified by the

hardware and at some point would not create any more copies content stamped with a visible watermark that is very difficult to remove so that it can be

publicly and freely distributed Prove ownership

Page | 7

21 Examples of watermarking

Reporting or recording certain information about how the watermarked media is being transmitted accessed or used

EXAMPLE Broadcast monitoring equipment in use today detects watermarks in broadcasts and uses them to generate automatic reports about when where and how often specific content is being aired

EXAMPLE Web crawlers or media player devices could look for watermarks in content they crawl or play and then record information about where and when specific marked files are found or played

Providing information to the individual user

EXAMPLE A media player device upon reading a watermark in a file the user is accessing could display additional information that might interest the user such as metadata (information about the content) a special commercial offer or confirmation that the content is genuine and has not been altered Enabling or disabling access to particular capabilities or content

EXAMPLE An online service upon reading a watermark in content a user is trying to access could provide the user with an updated or authorized version of the content Triggering an investigation complaint or even legal measures concerning a particular user or distributor of watermarked content

EXAMPLE Watermarks embedded in infringing copies of copyrighted media content could enable copyright holders to trace the copies back to particular users or distributors and potentially to launch legal action

Page | 8

3 Requirements of watermarks

To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria

1 The watermark must be difficult or impossible to remove at least without visibly degrading the original image2 The watermark must survive image modifications that are common to typical image-processing applications (eg scaling dithering cropping compression)3 An invisible watermark should be imperceptible so as not to affect the experience of viewing the image and4 For some invisible watermarking applications watermarks should be readily detectable the proper authorities even if imperceptible to the average observer Such decidability without requiring the original un-watermarked image would be necessary for efficient recovery of property and subsequent prosecution

One can understand the challenge of researchers in this field since the above requirements compete each with the others The litmus test of a watermarking method would be that it is accepted and used on a large commercial scale and that it stands up in a court of law None of the digital techniques have yet to meet these tests

Page | 9

4 Properties of digital watermarking techniques

The most important properties of digital watermarking techniques are transparency robustness security capacity invertibility (reversibility) and complexity and possibility of verification Based on these parameters the algorithms can be evaluated if a specific algorithm has adequate properties and can be used for a certain application area

From we define the parameter as follows

Transparency - Relates to the properties of the human sensory A transparent watermark causes no artifacts or quality loss

Robustness - Describes whether the watermark can be reliably detected after media operations It is important to note that robustness does not include attacks on the embedding scheme that are based on the knowledge of the embedding algorithm or on the availability of the detector function Robustness means resistance to ldquoblindrdquo non-targeted modifications or common media operations For example the Stirmark or 2Mosaik tools attack the robustness of watermarking algorithms with geometrical distortions For manipulation recognition the watermark has to be fragile to detect altered media

Security - Describes whether the embedded watermarking information cannot be removed beyond reliable detection by targeted attacks based on a full knowledge of the embedding algorithm and the detector except the key and the knowledge of at least one watermarked data The concept of security includes procedural attacks such as the IBM attack or attacks based on a partial knowledge of the carrier modifications due to message embedding or embedding of templates The security aspect also includes the false positive detection rates

Capacity - Describes how many information bits can be embedded It addresses also the possibility of embedding multiple watermarks in one document in parallel

Invertibility - Describes the possibility to produce the original data during the watermark retrieval

Complexity - Describes the effort and time we need to embed and retrieve a watermark This parameter is essential if we have real time applications Another aspect addresses

Page | 10

whether the original data in the retrieval process or not We need to distinguish between non-blind and blind watermarking schemes

5 Types of Digital Watermarks

Watermarks and watermarking techniques can be divided into various categories in various ways The watermarks can be applied in spatial domain An alternative to spatial domain watermarking is frequency domain watermarking It has been pointed out that the frequency domain methods are more robust than the spatial domain techniques Different types of watermarks are shown in the Figure

Fig 8 Typology of digital watermarking

Watermarking techniques can be divided into two categories according to the type of working domain-

51 Spatial domain

Spatial watermarking can also be applied using color separation In this way the watermark appears in only one of the color bands This renders the watermark visibly subtle such that it is difficult to detect under regular viewing However the mark appears immediately when the colors are separated for printing This renders the document useless for the printer unless the

Page | 11

watermark can be removed from the color band This approach is used commercially for journalists to inspect digital pictures from a photo-stock house before buying unmarked versions

52 Frequency domain

Frequency domain (and other transform domains) by first applying a transform like the Fast Fourier Transform (FFT) In a similar manner to spatial domain watermarking the values of chosen frequencies can be altered from the original Since high frequencies will be lost by compression or scaling the watermark signal is applied to lower frequencies or better yet applied adaptively to frequencies that contain important information of the original picture Since watermarks applied to the frequency domain will be dispersed over the entirety of the spatial image upon inverse transformation this method is not as susceptible to defeat by cropping as the spatial technique However there is more a tradeoff here between invisibility and decodability since the watermark is in effect applied indiscriminately across the spatial image

Watermarking techniques can be divided into four categories according to the type of document to be watermarked as follows

53 Text WatermarkingThe process of embeddinghiding data in text document can be termed as ldquotext watermarkingrdquo This can be use to protect electronic documents paper documents are easy to copy and distribute electronically

54 Image WatermarkingThe process of embeddinghiding data in image document can be termed as ldquoimage watermarkingrdquo This process is done by visible water marking and invisible watermarking

55 Audio WatermarkingThe process of embedding information into audio can be termed as audio watermarking Can be achieved by inserting information about the distributor and the buyer A watermark embedded within an audio stream to identify its origination

56 Video WatermarkingVideo watermarking involves embedding cryptographic information derived from frames of digital video into the video itself Because the watermark is part of the video rather than part of the file format this technology works independently of the video file format or codec

According to the human perception the digital watermarks can be divided into three different types as follows

Page | 12

57 Visible watermark

Visible watermarks are especially useful for conveying an immediate claim of ownership The main advantage is that they virtually eliminate the commercial value of the document to a would-be thief without lessening the documents utility for legitimate authorized purposes A familiar example is in the video domain where a logo is placed in a corner of the screen image

58 Invisible-Robust watermark

The invisible-robust watermark is embedded in such a way that alternations madeto the pixel value are perceptually not noticed and it can be recovered only with appropriate decoding mechanism

59 Invisible-Fragile watermarkThe invisible-fragile watermark is embedded in such a way that any manipulation or modification of the image would alter or destroy the watermark

510 Dual watermark

Dual watermark is a combination of a visible and an invisible watermark In this type of water mark an invisible watermark is used as a backup for the visible watermark as clear from the following diagram

Figure Schematic representation of dual watermarking

From application point of view digital watermark could be as below

511 source based

Source-based watermark are desirable for ownership identification or authentication where a unique watermark identifying the owner is introduced to all the copies of a particular image being distributed A source-based watermark could be used for authentication and to determine whether a received image or other electronic data has been tampered with

Page | 13

512 destination based

The watermark could also be destination based where each distributed copy gets a unique watermark identifying the particular buyer The destination based watermark could be used to trace the buyer in the case of illegal reselling

6 Digital Watermarking Techniques

61 Text-based Watermarking

62 Image Watermarking

63 Audio Watermarking

64 Video Watermarking

61Text-Based Watermarking Techniques

A The text watermarking based on the fine-tuning of document structure

This is a technique which makes the text as a binary image it obtains watermark through fine-tuning the display style and it is imperceptibly by human visual The most classic algorithm is proposed by Brassil and Maxemchuk it gives many different ways to insert watermark in the PostScript document as follows

a) Line-shift encoding for the line space of a text file is uniform the coding method embeds a watermark by vertical shifting an entire line when the movement away from no more than 1 300 inches the human eye cannot easily perceive by analyzing the line spacing can determine whether it contains text watermark the process does not require the participation of the original text

b) word-shift encoding this coding method embeds watermark by level shifting some special words in a line When a word is shifted to right or left itrsquos adjacent words are not moving not moving words are as references location for the process of decoding Experience found that the human eye cannot identify the 1 150 inches below the level of displacement As the document is not a fixed word spacing so to determine whether it contains watermark needs the text of the original documents

c) Characteristics coding the coding method inserts a marker by changing the particular characteristics of a letter such as changing the height of a individual letter fonts etc The above-mentioned three kinds of coding methods are to use the spatial characteristics of text to embed the watermark These algorithm entirely depend on the text format (line-shift word-shift characteristics coding etc) there are many shortcomings such as not enough antiaggressive less robust not well hidden

Page | 14

Fig 9 Text water markingB The text watermark based on the not important content For a text when some of the expressions of the text occur Some minor changes there is no impact for understanding the document for this point the text watermark can be embedded Typical methods include inserting punctuation in sentences or inserting space at the end of a line For example we can store binary information by setting or not setting the comma in the two side-by-side words with and or or to connect

Specifically if the guns butter and flowers expresses the logic 1 then the guns butter and flower is logic0Weakness of such method that is the watermark information may be missing in the transmission process of application In addition the source text can not be arbitrary This method is not currently the main method of text watermarking

C The text watermark based on ldquoreplace the content of textrdquo The method is derived from information hiding technology It looks source text as the significance sequence instead of text images embedded in the course of the text is converted to vector with the same or similar meaning of the text of the secret process So watermark can be embedded by converting the source text into the same or similar meaning of hidden text

Usually in the English text many words have synonyms such as big and 1arge smart and clever and so on so we can elect these specific words of the text constitute a synonym replacement tables The word needs to be replaced said logic 0 the words that do not need to replace the logic 1So the secret data can be hidden in the text the number of hidden data relates to the synonym appear frequency in the text the method also applies to Chinese text The method of synonym replacement hide information by modifying the contents of the text it not only has better robustness but also do not need to rely on a specific document format However this approach requires source text cannot be arbitrary that is should contain a certain number of synonyms have been defined and in the process of extracting information needs the synonyms replace table

D The text watermark Based on natural language processing technology

Natural language processing is to in some specific applications automatically handling the text written in natural language such as machine translation information retrieval information

Page | 15

extraction data mining and intelligent search engines and so on after many years of development of the Natural language processing technology much experience and techniques have been accumulated such as word segmentation syntax analysis restatement eliminate the ambiguity of words and so on These are the foundation of The text watermark Based on natural language processing technology and compared to previous methods through the use of natural language processing technology embedded watermark informationmore secure reliable

Challenges

Marking copies uniquely

Making necessary for a recipient to provide personal information

Using encryption

Uses

Protect electronic documents

Paper documents are easy to copy and distribute electronically

62 Image Watermarking TechniquesIn image watermarking technique different type of technique is used as Digital Image ndash artificial resemblance of original object stored in form of binary numbers Image Watermarking ndash putting in some information that ensures your authentication of the document in the image itself Spatial domain algorithms- Two robust spatial-domain watermarking algorithms for image copyright protection are described as

The first one is robust against compression filtering and cropping Like all published crop-proof algorithms the one proposed here requires the original image for mark recovery Robustness against compression and filtering is obtained by using the JPEG algorithm to decide on mark location and magnitude robustness against cropping is achieved through a repetition code

The second watermarking algorithm uses visual components and is robust against compression filtering scaling and moderate rotations

The Discrete Cosine Transform (DCT)The discrete cosine transform (DCT) helps separate the image into parts (or spectral sub-bands) of differing importance (with respect to the images visual quality) The DCT is similar to the discrete Fourier transform it transforms a signal or image from the spatial domain to the frequency domain

Page | 16

Fig 10 DCT process diagramThe discrete cosine transform (DCT) is a technique for converting a signal into elementary frequency components It is widely used in image compression

Image Histogram

An image histogram is a type of histogram which acts as a graphical representation of the tonal distribution in a digital image It plots the number of pixels for each tonal value By looking at the histogram for a specific image a viewer will be able to judge the entire tonal distribution at a glance63 Audio Watermarking TechniquesIn audio watermarking technique different type of technique is used as

LSB watermarking - Least Significant Bit algorithm that embedding watermark into the least important part of the primary image and the watermark can be extracted from the primary image

The idea behind this watermarking technique is the following if you see you image as a matrix NxM (where N and M are the dimension of the image) you can represent the value of the pixel in the position (ij) as a binary number this binary can be then divided in all of its bit so that you will have a most significant bit (the one that contains quite a lot of information and a least significant bit that contains few information)

Quantisation watermarking - A new method for watermarking based on vector quantisation is proposed It is efficient for implementation with conventional techniques and simulation results show its robustness under a variety of attacks It also represents superiority over existing algorithms

Wavelet transform domain algorithms - The wavelet transform-domain least-mean square (WTDLMS) algorithm is known to have in general a faster convergence rate than the time-domain LMS algorithm and can find many applications in signal processing and communications areas However the computational complexity of the wavelet filter bank is relatively high In this work we show how to exploit the redundancy which exists in the computation of the wavelet coefficients between successive iterations so as to significantly reduce the computational load of the algorithm

Page | 17

7 Applications of Digital Watermarking

There is a wide variety of applications for watermarking The requirements of watermarking systems are always based on the application as for obvious reasons there is no ldquouniversalrdquo watermarking method Although it has to be robust in general different level of required robustness can be identified besides the specific characteristics of the problem which make the watermarking a suitable solution Several applications are listed below

Owner identification ndash similar to copyright protection to establish ownership of the content

Copy protection ndash also known as copy control to prevent people from making illegal copies of copyrighted content

Content authentication ndash to detect modifications of the content as a sign of invalid authentication

Fingerprinting ndash sometimes referred as transaction tracking or traitor tracking to trace back illegal duplication and distribution of the content

Broadcast monitoring ndash specifically for advertisements and in entertainment industries to monitor content being broadcasted as contracted and by the authorized source

Medical applications ndash known as invertible watermarking to provide both authentication and confidentiality in a reversible manner without affecting the medical image in any way

Page | 18

8 Limitations of digital watermarking

In January 1997 a counterfeiting scheme has been demonstrated for a class of invertible feature-based frequency domain invisible watermarking algorithms This counterfeiting scheme could be used to subvert ownership claims because the recovery of the digital signature from a watermarked image requires a comparison with an original The counterfeiting scheme works by first creating a counterfeit watermarked copy from the genuine watermarked copy by effectively inverting the genuine watermark This inversion creates a counterfeit of the original image A comparison of the decoded versions of both yield the owners (authorized) and the forged (inverted) signature This the technique of establishing legitimate ownership recovering the signature watermark by comparing a watermarked image with the original image breaks down It can be shown that both the legitimate signature and counterfeiters signature inhere in both the watermarked and counterfeit watermarked copies Thus while it may be demonstrated that at least one recipient has a counterfeit watermarked copy it cannot be determined which it is

Page | 19

9 Proposed Work

In traditional symmetric watermarking schemes the key used for watermark embedding must be available at the watermark detector This leads to a security problem if the detectors are implemented in consumer devices that are spread all over the world So asymmetric watermarking schemes also named public key digital watermarking schemes attract more and more attentions In such a public key watermarking system the private key is used for watermarking embedding and the public key is used only for watermarking detection The private key is kept for secret and the watermarks cannot easily be removed with public key

We are actually concentrating on studying public key watermarking techniques to evaluate and compare their performance in comparison to private key water marking techniques

Page | 20

10 RESEARCH DIRECTIONS

101 Study on Watermarking Algorithm

Digital watermarking technology processing contains two cores watermark embedding algorithm and detection algorithm Robustness imperceptibility invisibility and security of digital watermarking is generally the focus of the requirements

102 Study on Watermarking Theory

Although there are many published articles on watermarking the current watermarking technology canrsquot yet fill the actual requirements of most users The lack of standards interoperability problems as well as a suit of accurate and realistic requirements to watermarking system is still hinder the development of digital watermarking technology

There are still many problems to be resolved In order to be more widely used digital watermarking should establish a series of standards or agreements such as the standards of watermark embedding detection and certification Different watermarking algorithm has different compatibility and that is obviously not conducive to promoting the application of digital watermarking

103 Study on Watermark Attack

The relationship between watermark attack and watermarking algorithm is the same as spear and shield they restrict each other and promote each other as well To develop the technologies combined with cryptography authentication and digital signature is probably the direction of resistance development to various attacks

Page | 21

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

Water mark embedding process

Page | 4

Page | 5

Page | 6

2 Purpose of Digital Watermarking Watermarks added to digital content serve a variety of purposes The following list details six purposes of digital watermarking

Fig 7 Pupose of digital watermarking

Identify a misappropriating person Trace the marked documentrsquos dissemination through the network to avoid unauthorized duplication and distribution of publicly available multimedia

content added to limit the number of copies created whereas the watermarks are modified by the

hardware and at some point would not create any more copies content stamped with a visible watermark that is very difficult to remove so that it can be

publicly and freely distributed Prove ownership

Page | 7

21 Examples of watermarking

Reporting or recording certain information about how the watermarked media is being transmitted accessed or used

EXAMPLE Broadcast monitoring equipment in use today detects watermarks in broadcasts and uses them to generate automatic reports about when where and how often specific content is being aired

EXAMPLE Web crawlers or media player devices could look for watermarks in content they crawl or play and then record information about where and when specific marked files are found or played

Providing information to the individual user

EXAMPLE A media player device upon reading a watermark in a file the user is accessing could display additional information that might interest the user such as metadata (information about the content) a special commercial offer or confirmation that the content is genuine and has not been altered Enabling or disabling access to particular capabilities or content

EXAMPLE An online service upon reading a watermark in content a user is trying to access could provide the user with an updated or authorized version of the content Triggering an investigation complaint or even legal measures concerning a particular user or distributor of watermarked content

EXAMPLE Watermarks embedded in infringing copies of copyrighted media content could enable copyright holders to trace the copies back to particular users or distributors and potentially to launch legal action

Page | 8

3 Requirements of watermarks

To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria

1 The watermark must be difficult or impossible to remove at least without visibly degrading the original image2 The watermark must survive image modifications that are common to typical image-processing applications (eg scaling dithering cropping compression)3 An invisible watermark should be imperceptible so as not to affect the experience of viewing the image and4 For some invisible watermarking applications watermarks should be readily detectable the proper authorities even if imperceptible to the average observer Such decidability without requiring the original un-watermarked image would be necessary for efficient recovery of property and subsequent prosecution

One can understand the challenge of researchers in this field since the above requirements compete each with the others The litmus test of a watermarking method would be that it is accepted and used on a large commercial scale and that it stands up in a court of law None of the digital techniques have yet to meet these tests

Page | 9

4 Properties of digital watermarking techniques

The most important properties of digital watermarking techniques are transparency robustness security capacity invertibility (reversibility) and complexity and possibility of verification Based on these parameters the algorithms can be evaluated if a specific algorithm has adequate properties and can be used for a certain application area

From we define the parameter as follows

Transparency - Relates to the properties of the human sensory A transparent watermark causes no artifacts or quality loss

Robustness - Describes whether the watermark can be reliably detected after media operations It is important to note that robustness does not include attacks on the embedding scheme that are based on the knowledge of the embedding algorithm or on the availability of the detector function Robustness means resistance to ldquoblindrdquo non-targeted modifications or common media operations For example the Stirmark or 2Mosaik tools attack the robustness of watermarking algorithms with geometrical distortions For manipulation recognition the watermark has to be fragile to detect altered media

Security - Describes whether the embedded watermarking information cannot be removed beyond reliable detection by targeted attacks based on a full knowledge of the embedding algorithm and the detector except the key and the knowledge of at least one watermarked data The concept of security includes procedural attacks such as the IBM attack or attacks based on a partial knowledge of the carrier modifications due to message embedding or embedding of templates The security aspect also includes the false positive detection rates

Capacity - Describes how many information bits can be embedded It addresses also the possibility of embedding multiple watermarks in one document in parallel

Invertibility - Describes the possibility to produce the original data during the watermark retrieval

Complexity - Describes the effort and time we need to embed and retrieve a watermark This parameter is essential if we have real time applications Another aspect addresses

Page | 10

whether the original data in the retrieval process or not We need to distinguish between non-blind and blind watermarking schemes

5 Types of Digital Watermarks

Watermarks and watermarking techniques can be divided into various categories in various ways The watermarks can be applied in spatial domain An alternative to spatial domain watermarking is frequency domain watermarking It has been pointed out that the frequency domain methods are more robust than the spatial domain techniques Different types of watermarks are shown in the Figure

Fig 8 Typology of digital watermarking

Watermarking techniques can be divided into two categories according to the type of working domain-

51 Spatial domain

Spatial watermarking can also be applied using color separation In this way the watermark appears in only one of the color bands This renders the watermark visibly subtle such that it is difficult to detect under regular viewing However the mark appears immediately when the colors are separated for printing This renders the document useless for the printer unless the

Page | 11

watermark can be removed from the color band This approach is used commercially for journalists to inspect digital pictures from a photo-stock house before buying unmarked versions

52 Frequency domain

Frequency domain (and other transform domains) by first applying a transform like the Fast Fourier Transform (FFT) In a similar manner to spatial domain watermarking the values of chosen frequencies can be altered from the original Since high frequencies will be lost by compression or scaling the watermark signal is applied to lower frequencies or better yet applied adaptively to frequencies that contain important information of the original picture Since watermarks applied to the frequency domain will be dispersed over the entirety of the spatial image upon inverse transformation this method is not as susceptible to defeat by cropping as the spatial technique However there is more a tradeoff here between invisibility and decodability since the watermark is in effect applied indiscriminately across the spatial image

Watermarking techniques can be divided into four categories according to the type of document to be watermarked as follows

53 Text WatermarkingThe process of embeddinghiding data in text document can be termed as ldquotext watermarkingrdquo This can be use to protect electronic documents paper documents are easy to copy and distribute electronically

54 Image WatermarkingThe process of embeddinghiding data in image document can be termed as ldquoimage watermarkingrdquo This process is done by visible water marking and invisible watermarking

55 Audio WatermarkingThe process of embedding information into audio can be termed as audio watermarking Can be achieved by inserting information about the distributor and the buyer A watermark embedded within an audio stream to identify its origination

56 Video WatermarkingVideo watermarking involves embedding cryptographic information derived from frames of digital video into the video itself Because the watermark is part of the video rather than part of the file format this technology works independently of the video file format or codec

According to the human perception the digital watermarks can be divided into three different types as follows

Page | 12

57 Visible watermark

Visible watermarks are especially useful for conveying an immediate claim of ownership The main advantage is that they virtually eliminate the commercial value of the document to a would-be thief without lessening the documents utility for legitimate authorized purposes A familiar example is in the video domain where a logo is placed in a corner of the screen image

58 Invisible-Robust watermark

The invisible-robust watermark is embedded in such a way that alternations madeto the pixel value are perceptually not noticed and it can be recovered only with appropriate decoding mechanism

59 Invisible-Fragile watermarkThe invisible-fragile watermark is embedded in such a way that any manipulation or modification of the image would alter or destroy the watermark

510 Dual watermark

Dual watermark is a combination of a visible and an invisible watermark In this type of water mark an invisible watermark is used as a backup for the visible watermark as clear from the following diagram

Figure Schematic representation of dual watermarking

From application point of view digital watermark could be as below

511 source based

Source-based watermark are desirable for ownership identification or authentication where a unique watermark identifying the owner is introduced to all the copies of a particular image being distributed A source-based watermark could be used for authentication and to determine whether a received image or other electronic data has been tampered with

Page | 13

512 destination based

The watermark could also be destination based where each distributed copy gets a unique watermark identifying the particular buyer The destination based watermark could be used to trace the buyer in the case of illegal reselling

6 Digital Watermarking Techniques

61 Text-based Watermarking

62 Image Watermarking

63 Audio Watermarking

64 Video Watermarking

61Text-Based Watermarking Techniques

A The text watermarking based on the fine-tuning of document structure

This is a technique which makes the text as a binary image it obtains watermark through fine-tuning the display style and it is imperceptibly by human visual The most classic algorithm is proposed by Brassil and Maxemchuk it gives many different ways to insert watermark in the PostScript document as follows

a) Line-shift encoding for the line space of a text file is uniform the coding method embeds a watermark by vertical shifting an entire line when the movement away from no more than 1 300 inches the human eye cannot easily perceive by analyzing the line spacing can determine whether it contains text watermark the process does not require the participation of the original text

b) word-shift encoding this coding method embeds watermark by level shifting some special words in a line When a word is shifted to right or left itrsquos adjacent words are not moving not moving words are as references location for the process of decoding Experience found that the human eye cannot identify the 1 150 inches below the level of displacement As the document is not a fixed word spacing so to determine whether it contains watermark needs the text of the original documents

c) Characteristics coding the coding method inserts a marker by changing the particular characteristics of a letter such as changing the height of a individual letter fonts etc The above-mentioned three kinds of coding methods are to use the spatial characteristics of text to embed the watermark These algorithm entirely depend on the text format (line-shift word-shift characteristics coding etc) there are many shortcomings such as not enough antiaggressive less robust not well hidden

Page | 14

Fig 9 Text water markingB The text watermark based on the not important content For a text when some of the expressions of the text occur Some minor changes there is no impact for understanding the document for this point the text watermark can be embedded Typical methods include inserting punctuation in sentences or inserting space at the end of a line For example we can store binary information by setting or not setting the comma in the two side-by-side words with and or or to connect

Specifically if the guns butter and flowers expresses the logic 1 then the guns butter and flower is logic0Weakness of such method that is the watermark information may be missing in the transmission process of application In addition the source text can not be arbitrary This method is not currently the main method of text watermarking

C The text watermark based on ldquoreplace the content of textrdquo The method is derived from information hiding technology It looks source text as the significance sequence instead of text images embedded in the course of the text is converted to vector with the same or similar meaning of the text of the secret process So watermark can be embedded by converting the source text into the same or similar meaning of hidden text

Usually in the English text many words have synonyms such as big and 1arge smart and clever and so on so we can elect these specific words of the text constitute a synonym replacement tables The word needs to be replaced said logic 0 the words that do not need to replace the logic 1So the secret data can be hidden in the text the number of hidden data relates to the synonym appear frequency in the text the method also applies to Chinese text The method of synonym replacement hide information by modifying the contents of the text it not only has better robustness but also do not need to rely on a specific document format However this approach requires source text cannot be arbitrary that is should contain a certain number of synonyms have been defined and in the process of extracting information needs the synonyms replace table

D The text watermark Based on natural language processing technology

Natural language processing is to in some specific applications automatically handling the text written in natural language such as machine translation information retrieval information

Page | 15

extraction data mining and intelligent search engines and so on after many years of development of the Natural language processing technology much experience and techniques have been accumulated such as word segmentation syntax analysis restatement eliminate the ambiguity of words and so on These are the foundation of The text watermark Based on natural language processing technology and compared to previous methods through the use of natural language processing technology embedded watermark informationmore secure reliable

Challenges

Marking copies uniquely

Making necessary for a recipient to provide personal information

Using encryption

Uses

Protect electronic documents

Paper documents are easy to copy and distribute electronically

62 Image Watermarking TechniquesIn image watermarking technique different type of technique is used as Digital Image ndash artificial resemblance of original object stored in form of binary numbers Image Watermarking ndash putting in some information that ensures your authentication of the document in the image itself Spatial domain algorithms- Two robust spatial-domain watermarking algorithms for image copyright protection are described as

The first one is robust against compression filtering and cropping Like all published crop-proof algorithms the one proposed here requires the original image for mark recovery Robustness against compression and filtering is obtained by using the JPEG algorithm to decide on mark location and magnitude robustness against cropping is achieved through a repetition code

The second watermarking algorithm uses visual components and is robust against compression filtering scaling and moderate rotations

The Discrete Cosine Transform (DCT)The discrete cosine transform (DCT) helps separate the image into parts (or spectral sub-bands) of differing importance (with respect to the images visual quality) The DCT is similar to the discrete Fourier transform it transforms a signal or image from the spatial domain to the frequency domain

Page | 16

Fig 10 DCT process diagramThe discrete cosine transform (DCT) is a technique for converting a signal into elementary frequency components It is widely used in image compression

Image Histogram

An image histogram is a type of histogram which acts as a graphical representation of the tonal distribution in a digital image It plots the number of pixels for each tonal value By looking at the histogram for a specific image a viewer will be able to judge the entire tonal distribution at a glance63 Audio Watermarking TechniquesIn audio watermarking technique different type of technique is used as

LSB watermarking - Least Significant Bit algorithm that embedding watermark into the least important part of the primary image and the watermark can be extracted from the primary image

The idea behind this watermarking technique is the following if you see you image as a matrix NxM (where N and M are the dimension of the image) you can represent the value of the pixel in the position (ij) as a binary number this binary can be then divided in all of its bit so that you will have a most significant bit (the one that contains quite a lot of information and a least significant bit that contains few information)

Quantisation watermarking - A new method for watermarking based on vector quantisation is proposed It is efficient for implementation with conventional techniques and simulation results show its robustness under a variety of attacks It also represents superiority over existing algorithms

Wavelet transform domain algorithms - The wavelet transform-domain least-mean square (WTDLMS) algorithm is known to have in general a faster convergence rate than the time-domain LMS algorithm and can find many applications in signal processing and communications areas However the computational complexity of the wavelet filter bank is relatively high In this work we show how to exploit the redundancy which exists in the computation of the wavelet coefficients between successive iterations so as to significantly reduce the computational load of the algorithm

Page | 17

7 Applications of Digital Watermarking

There is a wide variety of applications for watermarking The requirements of watermarking systems are always based on the application as for obvious reasons there is no ldquouniversalrdquo watermarking method Although it has to be robust in general different level of required robustness can be identified besides the specific characteristics of the problem which make the watermarking a suitable solution Several applications are listed below

Owner identification ndash similar to copyright protection to establish ownership of the content

Copy protection ndash also known as copy control to prevent people from making illegal copies of copyrighted content

Content authentication ndash to detect modifications of the content as a sign of invalid authentication

Fingerprinting ndash sometimes referred as transaction tracking or traitor tracking to trace back illegal duplication and distribution of the content

Broadcast monitoring ndash specifically for advertisements and in entertainment industries to monitor content being broadcasted as contracted and by the authorized source

Medical applications ndash known as invertible watermarking to provide both authentication and confidentiality in a reversible manner without affecting the medical image in any way

Page | 18

8 Limitations of digital watermarking

In January 1997 a counterfeiting scheme has been demonstrated for a class of invertible feature-based frequency domain invisible watermarking algorithms This counterfeiting scheme could be used to subvert ownership claims because the recovery of the digital signature from a watermarked image requires a comparison with an original The counterfeiting scheme works by first creating a counterfeit watermarked copy from the genuine watermarked copy by effectively inverting the genuine watermark This inversion creates a counterfeit of the original image A comparison of the decoded versions of both yield the owners (authorized) and the forged (inverted) signature This the technique of establishing legitimate ownership recovering the signature watermark by comparing a watermarked image with the original image breaks down It can be shown that both the legitimate signature and counterfeiters signature inhere in both the watermarked and counterfeit watermarked copies Thus while it may be demonstrated that at least one recipient has a counterfeit watermarked copy it cannot be determined which it is

Page | 19

9 Proposed Work

In traditional symmetric watermarking schemes the key used for watermark embedding must be available at the watermark detector This leads to a security problem if the detectors are implemented in consumer devices that are spread all over the world So asymmetric watermarking schemes also named public key digital watermarking schemes attract more and more attentions In such a public key watermarking system the private key is used for watermarking embedding and the public key is used only for watermarking detection The private key is kept for secret and the watermarks cannot easily be removed with public key

We are actually concentrating on studying public key watermarking techniques to evaluate and compare their performance in comparison to private key water marking techniques

Page | 20

10 RESEARCH DIRECTIONS

101 Study on Watermarking Algorithm

Digital watermarking technology processing contains two cores watermark embedding algorithm and detection algorithm Robustness imperceptibility invisibility and security of digital watermarking is generally the focus of the requirements

102 Study on Watermarking Theory

Although there are many published articles on watermarking the current watermarking technology canrsquot yet fill the actual requirements of most users The lack of standards interoperability problems as well as a suit of accurate and realistic requirements to watermarking system is still hinder the development of digital watermarking technology

There are still many problems to be resolved In order to be more widely used digital watermarking should establish a series of standards or agreements such as the standards of watermark embedding detection and certification Different watermarking algorithm has different compatibility and that is obviously not conducive to promoting the application of digital watermarking

103 Study on Watermark Attack

The relationship between watermark attack and watermarking algorithm is the same as spear and shield they restrict each other and promote each other as well To develop the technologies combined with cryptography authentication and digital signature is probably the direction of resistance development to various attacks

Page | 21

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

Page | 5

Page | 6

2 Purpose of Digital Watermarking Watermarks added to digital content serve a variety of purposes The following list details six purposes of digital watermarking

Fig 7 Pupose of digital watermarking

Identify a misappropriating person Trace the marked documentrsquos dissemination through the network to avoid unauthorized duplication and distribution of publicly available multimedia

content added to limit the number of copies created whereas the watermarks are modified by the

hardware and at some point would not create any more copies content stamped with a visible watermark that is very difficult to remove so that it can be

publicly and freely distributed Prove ownership

Page | 7

21 Examples of watermarking

Reporting or recording certain information about how the watermarked media is being transmitted accessed or used

EXAMPLE Broadcast monitoring equipment in use today detects watermarks in broadcasts and uses them to generate automatic reports about when where and how often specific content is being aired

EXAMPLE Web crawlers or media player devices could look for watermarks in content they crawl or play and then record information about where and when specific marked files are found or played

Providing information to the individual user

EXAMPLE A media player device upon reading a watermark in a file the user is accessing could display additional information that might interest the user such as metadata (information about the content) a special commercial offer or confirmation that the content is genuine and has not been altered Enabling or disabling access to particular capabilities or content

EXAMPLE An online service upon reading a watermark in content a user is trying to access could provide the user with an updated or authorized version of the content Triggering an investigation complaint or even legal measures concerning a particular user or distributor of watermarked content

EXAMPLE Watermarks embedded in infringing copies of copyrighted media content could enable copyright holders to trace the copies back to particular users or distributors and potentially to launch legal action

Page | 8

3 Requirements of watermarks

To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria

1 The watermark must be difficult or impossible to remove at least without visibly degrading the original image2 The watermark must survive image modifications that are common to typical image-processing applications (eg scaling dithering cropping compression)3 An invisible watermark should be imperceptible so as not to affect the experience of viewing the image and4 For some invisible watermarking applications watermarks should be readily detectable the proper authorities even if imperceptible to the average observer Such decidability without requiring the original un-watermarked image would be necessary for efficient recovery of property and subsequent prosecution

One can understand the challenge of researchers in this field since the above requirements compete each with the others The litmus test of a watermarking method would be that it is accepted and used on a large commercial scale and that it stands up in a court of law None of the digital techniques have yet to meet these tests

Page | 9

4 Properties of digital watermarking techniques

The most important properties of digital watermarking techniques are transparency robustness security capacity invertibility (reversibility) and complexity and possibility of verification Based on these parameters the algorithms can be evaluated if a specific algorithm has adequate properties and can be used for a certain application area

From we define the parameter as follows

Transparency - Relates to the properties of the human sensory A transparent watermark causes no artifacts or quality loss

Robustness - Describes whether the watermark can be reliably detected after media operations It is important to note that robustness does not include attacks on the embedding scheme that are based on the knowledge of the embedding algorithm or on the availability of the detector function Robustness means resistance to ldquoblindrdquo non-targeted modifications or common media operations For example the Stirmark or 2Mosaik tools attack the robustness of watermarking algorithms with geometrical distortions For manipulation recognition the watermark has to be fragile to detect altered media

Security - Describes whether the embedded watermarking information cannot be removed beyond reliable detection by targeted attacks based on a full knowledge of the embedding algorithm and the detector except the key and the knowledge of at least one watermarked data The concept of security includes procedural attacks such as the IBM attack or attacks based on a partial knowledge of the carrier modifications due to message embedding or embedding of templates The security aspect also includes the false positive detection rates

Capacity - Describes how many information bits can be embedded It addresses also the possibility of embedding multiple watermarks in one document in parallel

Invertibility - Describes the possibility to produce the original data during the watermark retrieval

Complexity - Describes the effort and time we need to embed and retrieve a watermark This parameter is essential if we have real time applications Another aspect addresses

Page | 10

whether the original data in the retrieval process or not We need to distinguish between non-blind and blind watermarking schemes

5 Types of Digital Watermarks

Watermarks and watermarking techniques can be divided into various categories in various ways The watermarks can be applied in spatial domain An alternative to spatial domain watermarking is frequency domain watermarking It has been pointed out that the frequency domain methods are more robust than the spatial domain techniques Different types of watermarks are shown in the Figure

Fig 8 Typology of digital watermarking

Watermarking techniques can be divided into two categories according to the type of working domain-

51 Spatial domain

Spatial watermarking can also be applied using color separation In this way the watermark appears in only one of the color bands This renders the watermark visibly subtle such that it is difficult to detect under regular viewing However the mark appears immediately when the colors are separated for printing This renders the document useless for the printer unless the

Page | 11

watermark can be removed from the color band This approach is used commercially for journalists to inspect digital pictures from a photo-stock house before buying unmarked versions

52 Frequency domain

Frequency domain (and other transform domains) by first applying a transform like the Fast Fourier Transform (FFT) In a similar manner to spatial domain watermarking the values of chosen frequencies can be altered from the original Since high frequencies will be lost by compression or scaling the watermark signal is applied to lower frequencies or better yet applied adaptively to frequencies that contain important information of the original picture Since watermarks applied to the frequency domain will be dispersed over the entirety of the spatial image upon inverse transformation this method is not as susceptible to defeat by cropping as the spatial technique However there is more a tradeoff here between invisibility and decodability since the watermark is in effect applied indiscriminately across the spatial image

Watermarking techniques can be divided into four categories according to the type of document to be watermarked as follows

53 Text WatermarkingThe process of embeddinghiding data in text document can be termed as ldquotext watermarkingrdquo This can be use to protect electronic documents paper documents are easy to copy and distribute electronically

54 Image WatermarkingThe process of embeddinghiding data in image document can be termed as ldquoimage watermarkingrdquo This process is done by visible water marking and invisible watermarking

55 Audio WatermarkingThe process of embedding information into audio can be termed as audio watermarking Can be achieved by inserting information about the distributor and the buyer A watermark embedded within an audio stream to identify its origination

56 Video WatermarkingVideo watermarking involves embedding cryptographic information derived from frames of digital video into the video itself Because the watermark is part of the video rather than part of the file format this technology works independently of the video file format or codec

According to the human perception the digital watermarks can be divided into three different types as follows

Page | 12

57 Visible watermark

Visible watermarks are especially useful for conveying an immediate claim of ownership The main advantage is that they virtually eliminate the commercial value of the document to a would-be thief without lessening the documents utility for legitimate authorized purposes A familiar example is in the video domain where a logo is placed in a corner of the screen image

58 Invisible-Robust watermark

The invisible-robust watermark is embedded in such a way that alternations madeto the pixel value are perceptually not noticed and it can be recovered only with appropriate decoding mechanism

59 Invisible-Fragile watermarkThe invisible-fragile watermark is embedded in such a way that any manipulation or modification of the image would alter or destroy the watermark

510 Dual watermark

Dual watermark is a combination of a visible and an invisible watermark In this type of water mark an invisible watermark is used as a backup for the visible watermark as clear from the following diagram

Figure Schematic representation of dual watermarking

From application point of view digital watermark could be as below

511 source based

Source-based watermark are desirable for ownership identification or authentication where a unique watermark identifying the owner is introduced to all the copies of a particular image being distributed A source-based watermark could be used for authentication and to determine whether a received image or other electronic data has been tampered with

Page | 13

512 destination based

The watermark could also be destination based where each distributed copy gets a unique watermark identifying the particular buyer The destination based watermark could be used to trace the buyer in the case of illegal reselling

6 Digital Watermarking Techniques

61 Text-based Watermarking

62 Image Watermarking

63 Audio Watermarking

64 Video Watermarking

61Text-Based Watermarking Techniques

A The text watermarking based on the fine-tuning of document structure

This is a technique which makes the text as a binary image it obtains watermark through fine-tuning the display style and it is imperceptibly by human visual The most classic algorithm is proposed by Brassil and Maxemchuk it gives many different ways to insert watermark in the PostScript document as follows

a) Line-shift encoding for the line space of a text file is uniform the coding method embeds a watermark by vertical shifting an entire line when the movement away from no more than 1 300 inches the human eye cannot easily perceive by analyzing the line spacing can determine whether it contains text watermark the process does not require the participation of the original text

b) word-shift encoding this coding method embeds watermark by level shifting some special words in a line When a word is shifted to right or left itrsquos adjacent words are not moving not moving words are as references location for the process of decoding Experience found that the human eye cannot identify the 1 150 inches below the level of displacement As the document is not a fixed word spacing so to determine whether it contains watermark needs the text of the original documents

c) Characteristics coding the coding method inserts a marker by changing the particular characteristics of a letter such as changing the height of a individual letter fonts etc The above-mentioned three kinds of coding methods are to use the spatial characteristics of text to embed the watermark These algorithm entirely depend on the text format (line-shift word-shift characteristics coding etc) there are many shortcomings such as not enough antiaggressive less robust not well hidden

Page | 14

Fig 9 Text water markingB The text watermark based on the not important content For a text when some of the expressions of the text occur Some minor changes there is no impact for understanding the document for this point the text watermark can be embedded Typical methods include inserting punctuation in sentences or inserting space at the end of a line For example we can store binary information by setting or not setting the comma in the two side-by-side words with and or or to connect

Specifically if the guns butter and flowers expresses the logic 1 then the guns butter and flower is logic0Weakness of such method that is the watermark information may be missing in the transmission process of application In addition the source text can not be arbitrary This method is not currently the main method of text watermarking

C The text watermark based on ldquoreplace the content of textrdquo The method is derived from information hiding technology It looks source text as the significance sequence instead of text images embedded in the course of the text is converted to vector with the same or similar meaning of the text of the secret process So watermark can be embedded by converting the source text into the same or similar meaning of hidden text

Usually in the English text many words have synonyms such as big and 1arge smart and clever and so on so we can elect these specific words of the text constitute a synonym replacement tables The word needs to be replaced said logic 0 the words that do not need to replace the logic 1So the secret data can be hidden in the text the number of hidden data relates to the synonym appear frequency in the text the method also applies to Chinese text The method of synonym replacement hide information by modifying the contents of the text it not only has better robustness but also do not need to rely on a specific document format However this approach requires source text cannot be arbitrary that is should contain a certain number of synonyms have been defined and in the process of extracting information needs the synonyms replace table

D The text watermark Based on natural language processing technology

Natural language processing is to in some specific applications automatically handling the text written in natural language such as machine translation information retrieval information

Page | 15

extraction data mining and intelligent search engines and so on after many years of development of the Natural language processing technology much experience and techniques have been accumulated such as word segmentation syntax analysis restatement eliminate the ambiguity of words and so on These are the foundation of The text watermark Based on natural language processing technology and compared to previous methods through the use of natural language processing technology embedded watermark informationmore secure reliable

Challenges

Marking copies uniquely

Making necessary for a recipient to provide personal information

Using encryption

Uses

Protect electronic documents

Paper documents are easy to copy and distribute electronically

62 Image Watermarking TechniquesIn image watermarking technique different type of technique is used as Digital Image ndash artificial resemblance of original object stored in form of binary numbers Image Watermarking ndash putting in some information that ensures your authentication of the document in the image itself Spatial domain algorithms- Two robust spatial-domain watermarking algorithms for image copyright protection are described as

The first one is robust against compression filtering and cropping Like all published crop-proof algorithms the one proposed here requires the original image for mark recovery Robustness against compression and filtering is obtained by using the JPEG algorithm to decide on mark location and magnitude robustness against cropping is achieved through a repetition code

The second watermarking algorithm uses visual components and is robust against compression filtering scaling and moderate rotations

The Discrete Cosine Transform (DCT)The discrete cosine transform (DCT) helps separate the image into parts (or spectral sub-bands) of differing importance (with respect to the images visual quality) The DCT is similar to the discrete Fourier transform it transforms a signal or image from the spatial domain to the frequency domain

Page | 16

Fig 10 DCT process diagramThe discrete cosine transform (DCT) is a technique for converting a signal into elementary frequency components It is widely used in image compression

Image Histogram

An image histogram is a type of histogram which acts as a graphical representation of the tonal distribution in a digital image It plots the number of pixels for each tonal value By looking at the histogram for a specific image a viewer will be able to judge the entire tonal distribution at a glance63 Audio Watermarking TechniquesIn audio watermarking technique different type of technique is used as

LSB watermarking - Least Significant Bit algorithm that embedding watermark into the least important part of the primary image and the watermark can be extracted from the primary image

The idea behind this watermarking technique is the following if you see you image as a matrix NxM (where N and M are the dimension of the image) you can represent the value of the pixel in the position (ij) as a binary number this binary can be then divided in all of its bit so that you will have a most significant bit (the one that contains quite a lot of information and a least significant bit that contains few information)

Quantisation watermarking - A new method for watermarking based on vector quantisation is proposed It is efficient for implementation with conventional techniques and simulation results show its robustness under a variety of attacks It also represents superiority over existing algorithms

Wavelet transform domain algorithms - The wavelet transform-domain least-mean square (WTDLMS) algorithm is known to have in general a faster convergence rate than the time-domain LMS algorithm and can find many applications in signal processing and communications areas However the computational complexity of the wavelet filter bank is relatively high In this work we show how to exploit the redundancy which exists in the computation of the wavelet coefficients between successive iterations so as to significantly reduce the computational load of the algorithm

Page | 17

7 Applications of Digital Watermarking

There is a wide variety of applications for watermarking The requirements of watermarking systems are always based on the application as for obvious reasons there is no ldquouniversalrdquo watermarking method Although it has to be robust in general different level of required robustness can be identified besides the specific characteristics of the problem which make the watermarking a suitable solution Several applications are listed below

Owner identification ndash similar to copyright protection to establish ownership of the content

Copy protection ndash also known as copy control to prevent people from making illegal copies of copyrighted content

Content authentication ndash to detect modifications of the content as a sign of invalid authentication

Fingerprinting ndash sometimes referred as transaction tracking or traitor tracking to trace back illegal duplication and distribution of the content

Broadcast monitoring ndash specifically for advertisements and in entertainment industries to monitor content being broadcasted as contracted and by the authorized source

Medical applications ndash known as invertible watermarking to provide both authentication and confidentiality in a reversible manner without affecting the medical image in any way

Page | 18

8 Limitations of digital watermarking

In January 1997 a counterfeiting scheme has been demonstrated for a class of invertible feature-based frequency domain invisible watermarking algorithms This counterfeiting scheme could be used to subvert ownership claims because the recovery of the digital signature from a watermarked image requires a comparison with an original The counterfeiting scheme works by first creating a counterfeit watermarked copy from the genuine watermarked copy by effectively inverting the genuine watermark This inversion creates a counterfeit of the original image A comparison of the decoded versions of both yield the owners (authorized) and the forged (inverted) signature This the technique of establishing legitimate ownership recovering the signature watermark by comparing a watermarked image with the original image breaks down It can be shown that both the legitimate signature and counterfeiters signature inhere in both the watermarked and counterfeit watermarked copies Thus while it may be demonstrated that at least one recipient has a counterfeit watermarked copy it cannot be determined which it is

Page | 19

9 Proposed Work

In traditional symmetric watermarking schemes the key used for watermark embedding must be available at the watermark detector This leads to a security problem if the detectors are implemented in consumer devices that are spread all over the world So asymmetric watermarking schemes also named public key digital watermarking schemes attract more and more attentions In such a public key watermarking system the private key is used for watermarking embedding and the public key is used only for watermarking detection The private key is kept for secret and the watermarks cannot easily be removed with public key

We are actually concentrating on studying public key watermarking techniques to evaluate and compare their performance in comparison to private key water marking techniques

Page | 20

10 RESEARCH DIRECTIONS

101 Study on Watermarking Algorithm

Digital watermarking technology processing contains two cores watermark embedding algorithm and detection algorithm Robustness imperceptibility invisibility and security of digital watermarking is generally the focus of the requirements

102 Study on Watermarking Theory

Although there are many published articles on watermarking the current watermarking technology canrsquot yet fill the actual requirements of most users The lack of standards interoperability problems as well as a suit of accurate and realistic requirements to watermarking system is still hinder the development of digital watermarking technology

There are still many problems to be resolved In order to be more widely used digital watermarking should establish a series of standards or agreements such as the standards of watermark embedding detection and certification Different watermarking algorithm has different compatibility and that is obviously not conducive to promoting the application of digital watermarking

103 Study on Watermark Attack

The relationship between watermark attack and watermarking algorithm is the same as spear and shield they restrict each other and promote each other as well To develop the technologies combined with cryptography authentication and digital signature is probably the direction of resistance development to various attacks

Page | 21

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

Page | 6

2 Purpose of Digital Watermarking Watermarks added to digital content serve a variety of purposes The following list details six purposes of digital watermarking

Fig 7 Pupose of digital watermarking

Identify a misappropriating person Trace the marked documentrsquos dissemination through the network to avoid unauthorized duplication and distribution of publicly available multimedia

content added to limit the number of copies created whereas the watermarks are modified by the

hardware and at some point would not create any more copies content stamped with a visible watermark that is very difficult to remove so that it can be

publicly and freely distributed Prove ownership

Page | 7

21 Examples of watermarking

Reporting or recording certain information about how the watermarked media is being transmitted accessed or used

EXAMPLE Broadcast monitoring equipment in use today detects watermarks in broadcasts and uses them to generate automatic reports about when where and how often specific content is being aired

EXAMPLE Web crawlers or media player devices could look for watermarks in content they crawl or play and then record information about where and when specific marked files are found or played

Providing information to the individual user

EXAMPLE A media player device upon reading a watermark in a file the user is accessing could display additional information that might interest the user such as metadata (information about the content) a special commercial offer or confirmation that the content is genuine and has not been altered Enabling or disabling access to particular capabilities or content

EXAMPLE An online service upon reading a watermark in content a user is trying to access could provide the user with an updated or authorized version of the content Triggering an investigation complaint or even legal measures concerning a particular user or distributor of watermarked content

EXAMPLE Watermarks embedded in infringing copies of copyrighted media content could enable copyright holders to trace the copies back to particular users or distributors and potentially to launch legal action

Page | 8

3 Requirements of watermarks

To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria

1 The watermark must be difficult or impossible to remove at least without visibly degrading the original image2 The watermark must survive image modifications that are common to typical image-processing applications (eg scaling dithering cropping compression)3 An invisible watermark should be imperceptible so as not to affect the experience of viewing the image and4 For some invisible watermarking applications watermarks should be readily detectable the proper authorities even if imperceptible to the average observer Such decidability without requiring the original un-watermarked image would be necessary for efficient recovery of property and subsequent prosecution

One can understand the challenge of researchers in this field since the above requirements compete each with the others The litmus test of a watermarking method would be that it is accepted and used on a large commercial scale and that it stands up in a court of law None of the digital techniques have yet to meet these tests

Page | 9

4 Properties of digital watermarking techniques

The most important properties of digital watermarking techniques are transparency robustness security capacity invertibility (reversibility) and complexity and possibility of verification Based on these parameters the algorithms can be evaluated if a specific algorithm has adequate properties and can be used for a certain application area

From we define the parameter as follows

Transparency - Relates to the properties of the human sensory A transparent watermark causes no artifacts or quality loss

Robustness - Describes whether the watermark can be reliably detected after media operations It is important to note that robustness does not include attacks on the embedding scheme that are based on the knowledge of the embedding algorithm or on the availability of the detector function Robustness means resistance to ldquoblindrdquo non-targeted modifications or common media operations For example the Stirmark or 2Mosaik tools attack the robustness of watermarking algorithms with geometrical distortions For manipulation recognition the watermark has to be fragile to detect altered media

Security - Describes whether the embedded watermarking information cannot be removed beyond reliable detection by targeted attacks based on a full knowledge of the embedding algorithm and the detector except the key and the knowledge of at least one watermarked data The concept of security includes procedural attacks such as the IBM attack or attacks based on a partial knowledge of the carrier modifications due to message embedding or embedding of templates The security aspect also includes the false positive detection rates

Capacity - Describes how many information bits can be embedded It addresses also the possibility of embedding multiple watermarks in one document in parallel

Invertibility - Describes the possibility to produce the original data during the watermark retrieval

Complexity - Describes the effort and time we need to embed and retrieve a watermark This parameter is essential if we have real time applications Another aspect addresses

Page | 10

whether the original data in the retrieval process or not We need to distinguish between non-blind and blind watermarking schemes

5 Types of Digital Watermarks

Watermarks and watermarking techniques can be divided into various categories in various ways The watermarks can be applied in spatial domain An alternative to spatial domain watermarking is frequency domain watermarking It has been pointed out that the frequency domain methods are more robust than the spatial domain techniques Different types of watermarks are shown in the Figure

Fig 8 Typology of digital watermarking

Watermarking techniques can be divided into two categories according to the type of working domain-

51 Spatial domain

Spatial watermarking can also be applied using color separation In this way the watermark appears in only one of the color bands This renders the watermark visibly subtle such that it is difficult to detect under regular viewing However the mark appears immediately when the colors are separated for printing This renders the document useless for the printer unless the

Page | 11

watermark can be removed from the color band This approach is used commercially for journalists to inspect digital pictures from a photo-stock house before buying unmarked versions

52 Frequency domain

Frequency domain (and other transform domains) by first applying a transform like the Fast Fourier Transform (FFT) In a similar manner to spatial domain watermarking the values of chosen frequencies can be altered from the original Since high frequencies will be lost by compression or scaling the watermark signal is applied to lower frequencies or better yet applied adaptively to frequencies that contain important information of the original picture Since watermarks applied to the frequency domain will be dispersed over the entirety of the spatial image upon inverse transformation this method is not as susceptible to defeat by cropping as the spatial technique However there is more a tradeoff here between invisibility and decodability since the watermark is in effect applied indiscriminately across the spatial image

Watermarking techniques can be divided into four categories according to the type of document to be watermarked as follows

53 Text WatermarkingThe process of embeddinghiding data in text document can be termed as ldquotext watermarkingrdquo This can be use to protect electronic documents paper documents are easy to copy and distribute electronically

54 Image WatermarkingThe process of embeddinghiding data in image document can be termed as ldquoimage watermarkingrdquo This process is done by visible water marking and invisible watermarking

55 Audio WatermarkingThe process of embedding information into audio can be termed as audio watermarking Can be achieved by inserting information about the distributor and the buyer A watermark embedded within an audio stream to identify its origination

56 Video WatermarkingVideo watermarking involves embedding cryptographic information derived from frames of digital video into the video itself Because the watermark is part of the video rather than part of the file format this technology works independently of the video file format or codec

According to the human perception the digital watermarks can be divided into three different types as follows

Page | 12

57 Visible watermark

Visible watermarks are especially useful for conveying an immediate claim of ownership The main advantage is that they virtually eliminate the commercial value of the document to a would-be thief without lessening the documents utility for legitimate authorized purposes A familiar example is in the video domain where a logo is placed in a corner of the screen image

58 Invisible-Robust watermark

The invisible-robust watermark is embedded in such a way that alternations madeto the pixel value are perceptually not noticed and it can be recovered only with appropriate decoding mechanism

59 Invisible-Fragile watermarkThe invisible-fragile watermark is embedded in such a way that any manipulation or modification of the image would alter or destroy the watermark

510 Dual watermark

Dual watermark is a combination of a visible and an invisible watermark In this type of water mark an invisible watermark is used as a backup for the visible watermark as clear from the following diagram

Figure Schematic representation of dual watermarking

From application point of view digital watermark could be as below

511 source based

Source-based watermark are desirable for ownership identification or authentication where a unique watermark identifying the owner is introduced to all the copies of a particular image being distributed A source-based watermark could be used for authentication and to determine whether a received image or other electronic data has been tampered with

Page | 13

512 destination based

The watermark could also be destination based where each distributed copy gets a unique watermark identifying the particular buyer The destination based watermark could be used to trace the buyer in the case of illegal reselling

6 Digital Watermarking Techniques

61 Text-based Watermarking

62 Image Watermarking

63 Audio Watermarking

64 Video Watermarking

61Text-Based Watermarking Techniques

A The text watermarking based on the fine-tuning of document structure

This is a technique which makes the text as a binary image it obtains watermark through fine-tuning the display style and it is imperceptibly by human visual The most classic algorithm is proposed by Brassil and Maxemchuk it gives many different ways to insert watermark in the PostScript document as follows

a) Line-shift encoding for the line space of a text file is uniform the coding method embeds a watermark by vertical shifting an entire line when the movement away from no more than 1 300 inches the human eye cannot easily perceive by analyzing the line spacing can determine whether it contains text watermark the process does not require the participation of the original text

b) word-shift encoding this coding method embeds watermark by level shifting some special words in a line When a word is shifted to right or left itrsquos adjacent words are not moving not moving words are as references location for the process of decoding Experience found that the human eye cannot identify the 1 150 inches below the level of displacement As the document is not a fixed word spacing so to determine whether it contains watermark needs the text of the original documents

c) Characteristics coding the coding method inserts a marker by changing the particular characteristics of a letter such as changing the height of a individual letter fonts etc The above-mentioned three kinds of coding methods are to use the spatial characteristics of text to embed the watermark These algorithm entirely depend on the text format (line-shift word-shift characteristics coding etc) there are many shortcomings such as not enough antiaggressive less robust not well hidden

Page | 14

Fig 9 Text water markingB The text watermark based on the not important content For a text when some of the expressions of the text occur Some minor changes there is no impact for understanding the document for this point the text watermark can be embedded Typical methods include inserting punctuation in sentences or inserting space at the end of a line For example we can store binary information by setting or not setting the comma in the two side-by-side words with and or or to connect

Specifically if the guns butter and flowers expresses the logic 1 then the guns butter and flower is logic0Weakness of such method that is the watermark information may be missing in the transmission process of application In addition the source text can not be arbitrary This method is not currently the main method of text watermarking

C The text watermark based on ldquoreplace the content of textrdquo The method is derived from information hiding technology It looks source text as the significance sequence instead of text images embedded in the course of the text is converted to vector with the same or similar meaning of the text of the secret process So watermark can be embedded by converting the source text into the same or similar meaning of hidden text

Usually in the English text many words have synonyms such as big and 1arge smart and clever and so on so we can elect these specific words of the text constitute a synonym replacement tables The word needs to be replaced said logic 0 the words that do not need to replace the logic 1So the secret data can be hidden in the text the number of hidden data relates to the synonym appear frequency in the text the method also applies to Chinese text The method of synonym replacement hide information by modifying the contents of the text it not only has better robustness but also do not need to rely on a specific document format However this approach requires source text cannot be arbitrary that is should contain a certain number of synonyms have been defined and in the process of extracting information needs the synonyms replace table

D The text watermark Based on natural language processing technology

Natural language processing is to in some specific applications automatically handling the text written in natural language such as machine translation information retrieval information

Page | 15

extraction data mining and intelligent search engines and so on after many years of development of the Natural language processing technology much experience and techniques have been accumulated such as word segmentation syntax analysis restatement eliminate the ambiguity of words and so on These are the foundation of The text watermark Based on natural language processing technology and compared to previous methods through the use of natural language processing technology embedded watermark informationmore secure reliable

Challenges

Marking copies uniquely

Making necessary for a recipient to provide personal information

Using encryption

Uses

Protect electronic documents

Paper documents are easy to copy and distribute electronically

62 Image Watermarking TechniquesIn image watermarking technique different type of technique is used as Digital Image ndash artificial resemblance of original object stored in form of binary numbers Image Watermarking ndash putting in some information that ensures your authentication of the document in the image itself Spatial domain algorithms- Two robust spatial-domain watermarking algorithms for image copyright protection are described as

The first one is robust against compression filtering and cropping Like all published crop-proof algorithms the one proposed here requires the original image for mark recovery Robustness against compression and filtering is obtained by using the JPEG algorithm to decide on mark location and magnitude robustness against cropping is achieved through a repetition code

The second watermarking algorithm uses visual components and is robust against compression filtering scaling and moderate rotations

The Discrete Cosine Transform (DCT)The discrete cosine transform (DCT) helps separate the image into parts (or spectral sub-bands) of differing importance (with respect to the images visual quality) The DCT is similar to the discrete Fourier transform it transforms a signal or image from the spatial domain to the frequency domain

Page | 16

Fig 10 DCT process diagramThe discrete cosine transform (DCT) is a technique for converting a signal into elementary frequency components It is widely used in image compression

Image Histogram

An image histogram is a type of histogram which acts as a graphical representation of the tonal distribution in a digital image It plots the number of pixels for each tonal value By looking at the histogram for a specific image a viewer will be able to judge the entire tonal distribution at a glance63 Audio Watermarking TechniquesIn audio watermarking technique different type of technique is used as

LSB watermarking - Least Significant Bit algorithm that embedding watermark into the least important part of the primary image and the watermark can be extracted from the primary image

The idea behind this watermarking technique is the following if you see you image as a matrix NxM (where N and M are the dimension of the image) you can represent the value of the pixel in the position (ij) as a binary number this binary can be then divided in all of its bit so that you will have a most significant bit (the one that contains quite a lot of information and a least significant bit that contains few information)

Quantisation watermarking - A new method for watermarking based on vector quantisation is proposed It is efficient for implementation with conventional techniques and simulation results show its robustness under a variety of attacks It also represents superiority over existing algorithms

Wavelet transform domain algorithms - The wavelet transform-domain least-mean square (WTDLMS) algorithm is known to have in general a faster convergence rate than the time-domain LMS algorithm and can find many applications in signal processing and communications areas However the computational complexity of the wavelet filter bank is relatively high In this work we show how to exploit the redundancy which exists in the computation of the wavelet coefficients between successive iterations so as to significantly reduce the computational load of the algorithm

Page | 17

7 Applications of Digital Watermarking

There is a wide variety of applications for watermarking The requirements of watermarking systems are always based on the application as for obvious reasons there is no ldquouniversalrdquo watermarking method Although it has to be robust in general different level of required robustness can be identified besides the specific characteristics of the problem which make the watermarking a suitable solution Several applications are listed below

Owner identification ndash similar to copyright protection to establish ownership of the content

Copy protection ndash also known as copy control to prevent people from making illegal copies of copyrighted content

Content authentication ndash to detect modifications of the content as a sign of invalid authentication

Fingerprinting ndash sometimes referred as transaction tracking or traitor tracking to trace back illegal duplication and distribution of the content

Broadcast monitoring ndash specifically for advertisements and in entertainment industries to monitor content being broadcasted as contracted and by the authorized source

Medical applications ndash known as invertible watermarking to provide both authentication and confidentiality in a reversible manner without affecting the medical image in any way

Page | 18

8 Limitations of digital watermarking

In January 1997 a counterfeiting scheme has been demonstrated for a class of invertible feature-based frequency domain invisible watermarking algorithms This counterfeiting scheme could be used to subvert ownership claims because the recovery of the digital signature from a watermarked image requires a comparison with an original The counterfeiting scheme works by first creating a counterfeit watermarked copy from the genuine watermarked copy by effectively inverting the genuine watermark This inversion creates a counterfeit of the original image A comparison of the decoded versions of both yield the owners (authorized) and the forged (inverted) signature This the technique of establishing legitimate ownership recovering the signature watermark by comparing a watermarked image with the original image breaks down It can be shown that both the legitimate signature and counterfeiters signature inhere in both the watermarked and counterfeit watermarked copies Thus while it may be demonstrated that at least one recipient has a counterfeit watermarked copy it cannot be determined which it is

Page | 19

9 Proposed Work

In traditional symmetric watermarking schemes the key used for watermark embedding must be available at the watermark detector This leads to a security problem if the detectors are implemented in consumer devices that are spread all over the world So asymmetric watermarking schemes also named public key digital watermarking schemes attract more and more attentions In such a public key watermarking system the private key is used for watermarking embedding and the public key is used only for watermarking detection The private key is kept for secret and the watermarks cannot easily be removed with public key

We are actually concentrating on studying public key watermarking techniques to evaluate and compare their performance in comparison to private key water marking techniques

Page | 20

10 RESEARCH DIRECTIONS

101 Study on Watermarking Algorithm

Digital watermarking technology processing contains two cores watermark embedding algorithm and detection algorithm Robustness imperceptibility invisibility and security of digital watermarking is generally the focus of the requirements

102 Study on Watermarking Theory

Although there are many published articles on watermarking the current watermarking technology canrsquot yet fill the actual requirements of most users The lack of standards interoperability problems as well as a suit of accurate and realistic requirements to watermarking system is still hinder the development of digital watermarking technology

There are still many problems to be resolved In order to be more widely used digital watermarking should establish a series of standards or agreements such as the standards of watermark embedding detection and certification Different watermarking algorithm has different compatibility and that is obviously not conducive to promoting the application of digital watermarking

103 Study on Watermark Attack

The relationship between watermark attack and watermarking algorithm is the same as spear and shield they restrict each other and promote each other as well To develop the technologies combined with cryptography authentication and digital signature is probably the direction of resistance development to various attacks

Page | 21

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

2 Purpose of Digital Watermarking Watermarks added to digital content serve a variety of purposes The following list details six purposes of digital watermarking

Fig 7 Pupose of digital watermarking

Identify a misappropriating person Trace the marked documentrsquos dissemination through the network to avoid unauthorized duplication and distribution of publicly available multimedia

content added to limit the number of copies created whereas the watermarks are modified by the

hardware and at some point would not create any more copies content stamped with a visible watermark that is very difficult to remove so that it can be

publicly and freely distributed Prove ownership

Page | 7

21 Examples of watermarking

Reporting or recording certain information about how the watermarked media is being transmitted accessed or used

EXAMPLE Broadcast monitoring equipment in use today detects watermarks in broadcasts and uses them to generate automatic reports about when where and how often specific content is being aired

EXAMPLE Web crawlers or media player devices could look for watermarks in content they crawl or play and then record information about where and when specific marked files are found or played

Providing information to the individual user

EXAMPLE A media player device upon reading a watermark in a file the user is accessing could display additional information that might interest the user such as metadata (information about the content) a special commercial offer or confirmation that the content is genuine and has not been altered Enabling or disabling access to particular capabilities or content

EXAMPLE An online service upon reading a watermark in content a user is trying to access could provide the user with an updated or authorized version of the content Triggering an investigation complaint or even legal measures concerning a particular user or distributor of watermarked content

EXAMPLE Watermarks embedded in infringing copies of copyrighted media content could enable copyright holders to trace the copies back to particular users or distributors and potentially to launch legal action

Page | 8

3 Requirements of watermarks

To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria

1 The watermark must be difficult or impossible to remove at least without visibly degrading the original image2 The watermark must survive image modifications that are common to typical image-processing applications (eg scaling dithering cropping compression)3 An invisible watermark should be imperceptible so as not to affect the experience of viewing the image and4 For some invisible watermarking applications watermarks should be readily detectable the proper authorities even if imperceptible to the average observer Such decidability without requiring the original un-watermarked image would be necessary for efficient recovery of property and subsequent prosecution

One can understand the challenge of researchers in this field since the above requirements compete each with the others The litmus test of a watermarking method would be that it is accepted and used on a large commercial scale and that it stands up in a court of law None of the digital techniques have yet to meet these tests

Page | 9

4 Properties of digital watermarking techniques

The most important properties of digital watermarking techniques are transparency robustness security capacity invertibility (reversibility) and complexity and possibility of verification Based on these parameters the algorithms can be evaluated if a specific algorithm has adequate properties and can be used for a certain application area

From we define the parameter as follows

Transparency - Relates to the properties of the human sensory A transparent watermark causes no artifacts or quality loss

Robustness - Describes whether the watermark can be reliably detected after media operations It is important to note that robustness does not include attacks on the embedding scheme that are based on the knowledge of the embedding algorithm or on the availability of the detector function Robustness means resistance to ldquoblindrdquo non-targeted modifications or common media operations For example the Stirmark or 2Mosaik tools attack the robustness of watermarking algorithms with geometrical distortions For manipulation recognition the watermark has to be fragile to detect altered media

Security - Describes whether the embedded watermarking information cannot be removed beyond reliable detection by targeted attacks based on a full knowledge of the embedding algorithm and the detector except the key and the knowledge of at least one watermarked data The concept of security includes procedural attacks such as the IBM attack or attacks based on a partial knowledge of the carrier modifications due to message embedding or embedding of templates The security aspect also includes the false positive detection rates

Capacity - Describes how many information bits can be embedded It addresses also the possibility of embedding multiple watermarks in one document in parallel

Invertibility - Describes the possibility to produce the original data during the watermark retrieval

Complexity - Describes the effort and time we need to embed and retrieve a watermark This parameter is essential if we have real time applications Another aspect addresses

Page | 10

whether the original data in the retrieval process or not We need to distinguish between non-blind and blind watermarking schemes

5 Types of Digital Watermarks

Watermarks and watermarking techniques can be divided into various categories in various ways The watermarks can be applied in spatial domain An alternative to spatial domain watermarking is frequency domain watermarking It has been pointed out that the frequency domain methods are more robust than the spatial domain techniques Different types of watermarks are shown in the Figure

Fig 8 Typology of digital watermarking

Watermarking techniques can be divided into two categories according to the type of working domain-

51 Spatial domain

Spatial watermarking can also be applied using color separation In this way the watermark appears in only one of the color bands This renders the watermark visibly subtle such that it is difficult to detect under regular viewing However the mark appears immediately when the colors are separated for printing This renders the document useless for the printer unless the

Page | 11

watermark can be removed from the color band This approach is used commercially for journalists to inspect digital pictures from a photo-stock house before buying unmarked versions

52 Frequency domain

Frequency domain (and other transform domains) by first applying a transform like the Fast Fourier Transform (FFT) In a similar manner to spatial domain watermarking the values of chosen frequencies can be altered from the original Since high frequencies will be lost by compression or scaling the watermark signal is applied to lower frequencies or better yet applied adaptively to frequencies that contain important information of the original picture Since watermarks applied to the frequency domain will be dispersed over the entirety of the spatial image upon inverse transformation this method is not as susceptible to defeat by cropping as the spatial technique However there is more a tradeoff here between invisibility and decodability since the watermark is in effect applied indiscriminately across the spatial image

Watermarking techniques can be divided into four categories according to the type of document to be watermarked as follows

53 Text WatermarkingThe process of embeddinghiding data in text document can be termed as ldquotext watermarkingrdquo This can be use to protect electronic documents paper documents are easy to copy and distribute electronically

54 Image WatermarkingThe process of embeddinghiding data in image document can be termed as ldquoimage watermarkingrdquo This process is done by visible water marking and invisible watermarking

55 Audio WatermarkingThe process of embedding information into audio can be termed as audio watermarking Can be achieved by inserting information about the distributor and the buyer A watermark embedded within an audio stream to identify its origination

56 Video WatermarkingVideo watermarking involves embedding cryptographic information derived from frames of digital video into the video itself Because the watermark is part of the video rather than part of the file format this technology works independently of the video file format or codec

According to the human perception the digital watermarks can be divided into three different types as follows

Page | 12

57 Visible watermark

Visible watermarks are especially useful for conveying an immediate claim of ownership The main advantage is that they virtually eliminate the commercial value of the document to a would-be thief without lessening the documents utility for legitimate authorized purposes A familiar example is in the video domain where a logo is placed in a corner of the screen image

58 Invisible-Robust watermark

The invisible-robust watermark is embedded in such a way that alternations madeto the pixel value are perceptually not noticed and it can be recovered only with appropriate decoding mechanism

59 Invisible-Fragile watermarkThe invisible-fragile watermark is embedded in such a way that any manipulation or modification of the image would alter or destroy the watermark

510 Dual watermark

Dual watermark is a combination of a visible and an invisible watermark In this type of water mark an invisible watermark is used as a backup for the visible watermark as clear from the following diagram

Figure Schematic representation of dual watermarking

From application point of view digital watermark could be as below

511 source based

Source-based watermark are desirable for ownership identification or authentication where a unique watermark identifying the owner is introduced to all the copies of a particular image being distributed A source-based watermark could be used for authentication and to determine whether a received image or other electronic data has been tampered with

Page | 13

512 destination based

The watermark could also be destination based where each distributed copy gets a unique watermark identifying the particular buyer The destination based watermark could be used to trace the buyer in the case of illegal reselling

6 Digital Watermarking Techniques

61 Text-based Watermarking

62 Image Watermarking

63 Audio Watermarking

64 Video Watermarking

61Text-Based Watermarking Techniques

A The text watermarking based on the fine-tuning of document structure

This is a technique which makes the text as a binary image it obtains watermark through fine-tuning the display style and it is imperceptibly by human visual The most classic algorithm is proposed by Brassil and Maxemchuk it gives many different ways to insert watermark in the PostScript document as follows

a) Line-shift encoding for the line space of a text file is uniform the coding method embeds a watermark by vertical shifting an entire line when the movement away from no more than 1 300 inches the human eye cannot easily perceive by analyzing the line spacing can determine whether it contains text watermark the process does not require the participation of the original text

b) word-shift encoding this coding method embeds watermark by level shifting some special words in a line When a word is shifted to right or left itrsquos adjacent words are not moving not moving words are as references location for the process of decoding Experience found that the human eye cannot identify the 1 150 inches below the level of displacement As the document is not a fixed word spacing so to determine whether it contains watermark needs the text of the original documents

c) Characteristics coding the coding method inserts a marker by changing the particular characteristics of a letter such as changing the height of a individual letter fonts etc The above-mentioned three kinds of coding methods are to use the spatial characteristics of text to embed the watermark These algorithm entirely depend on the text format (line-shift word-shift characteristics coding etc) there are many shortcomings such as not enough antiaggressive less robust not well hidden

Page | 14

Fig 9 Text water markingB The text watermark based on the not important content For a text when some of the expressions of the text occur Some minor changes there is no impact for understanding the document for this point the text watermark can be embedded Typical methods include inserting punctuation in sentences or inserting space at the end of a line For example we can store binary information by setting or not setting the comma in the two side-by-side words with and or or to connect

Specifically if the guns butter and flowers expresses the logic 1 then the guns butter and flower is logic0Weakness of such method that is the watermark information may be missing in the transmission process of application In addition the source text can not be arbitrary This method is not currently the main method of text watermarking

C The text watermark based on ldquoreplace the content of textrdquo The method is derived from information hiding technology It looks source text as the significance sequence instead of text images embedded in the course of the text is converted to vector with the same or similar meaning of the text of the secret process So watermark can be embedded by converting the source text into the same or similar meaning of hidden text

Usually in the English text many words have synonyms such as big and 1arge smart and clever and so on so we can elect these specific words of the text constitute a synonym replacement tables The word needs to be replaced said logic 0 the words that do not need to replace the logic 1So the secret data can be hidden in the text the number of hidden data relates to the synonym appear frequency in the text the method also applies to Chinese text The method of synonym replacement hide information by modifying the contents of the text it not only has better robustness but also do not need to rely on a specific document format However this approach requires source text cannot be arbitrary that is should contain a certain number of synonyms have been defined and in the process of extracting information needs the synonyms replace table

D The text watermark Based on natural language processing technology

Natural language processing is to in some specific applications automatically handling the text written in natural language such as machine translation information retrieval information

Page | 15

extraction data mining and intelligent search engines and so on after many years of development of the Natural language processing technology much experience and techniques have been accumulated such as word segmentation syntax analysis restatement eliminate the ambiguity of words and so on These are the foundation of The text watermark Based on natural language processing technology and compared to previous methods through the use of natural language processing technology embedded watermark informationmore secure reliable

Challenges

Marking copies uniquely

Making necessary for a recipient to provide personal information

Using encryption

Uses

Protect electronic documents

Paper documents are easy to copy and distribute electronically

62 Image Watermarking TechniquesIn image watermarking technique different type of technique is used as Digital Image ndash artificial resemblance of original object stored in form of binary numbers Image Watermarking ndash putting in some information that ensures your authentication of the document in the image itself Spatial domain algorithms- Two robust spatial-domain watermarking algorithms for image copyright protection are described as

The first one is robust against compression filtering and cropping Like all published crop-proof algorithms the one proposed here requires the original image for mark recovery Robustness against compression and filtering is obtained by using the JPEG algorithm to decide on mark location and magnitude robustness against cropping is achieved through a repetition code

The second watermarking algorithm uses visual components and is robust against compression filtering scaling and moderate rotations

The Discrete Cosine Transform (DCT)The discrete cosine transform (DCT) helps separate the image into parts (or spectral sub-bands) of differing importance (with respect to the images visual quality) The DCT is similar to the discrete Fourier transform it transforms a signal or image from the spatial domain to the frequency domain

Page | 16

Fig 10 DCT process diagramThe discrete cosine transform (DCT) is a technique for converting a signal into elementary frequency components It is widely used in image compression

Image Histogram

An image histogram is a type of histogram which acts as a graphical representation of the tonal distribution in a digital image It plots the number of pixels for each tonal value By looking at the histogram for a specific image a viewer will be able to judge the entire tonal distribution at a glance63 Audio Watermarking TechniquesIn audio watermarking technique different type of technique is used as

LSB watermarking - Least Significant Bit algorithm that embedding watermark into the least important part of the primary image and the watermark can be extracted from the primary image

The idea behind this watermarking technique is the following if you see you image as a matrix NxM (where N and M are the dimension of the image) you can represent the value of the pixel in the position (ij) as a binary number this binary can be then divided in all of its bit so that you will have a most significant bit (the one that contains quite a lot of information and a least significant bit that contains few information)

Quantisation watermarking - A new method for watermarking based on vector quantisation is proposed It is efficient for implementation with conventional techniques and simulation results show its robustness under a variety of attacks It also represents superiority over existing algorithms

Wavelet transform domain algorithms - The wavelet transform-domain least-mean square (WTDLMS) algorithm is known to have in general a faster convergence rate than the time-domain LMS algorithm and can find many applications in signal processing and communications areas However the computational complexity of the wavelet filter bank is relatively high In this work we show how to exploit the redundancy which exists in the computation of the wavelet coefficients between successive iterations so as to significantly reduce the computational load of the algorithm

Page | 17

7 Applications of Digital Watermarking

There is a wide variety of applications for watermarking The requirements of watermarking systems are always based on the application as for obvious reasons there is no ldquouniversalrdquo watermarking method Although it has to be robust in general different level of required robustness can be identified besides the specific characteristics of the problem which make the watermarking a suitable solution Several applications are listed below

Owner identification ndash similar to copyright protection to establish ownership of the content

Copy protection ndash also known as copy control to prevent people from making illegal copies of copyrighted content

Content authentication ndash to detect modifications of the content as a sign of invalid authentication

Fingerprinting ndash sometimes referred as transaction tracking or traitor tracking to trace back illegal duplication and distribution of the content

Broadcast monitoring ndash specifically for advertisements and in entertainment industries to monitor content being broadcasted as contracted and by the authorized source

Medical applications ndash known as invertible watermarking to provide both authentication and confidentiality in a reversible manner without affecting the medical image in any way

Page | 18

8 Limitations of digital watermarking

In January 1997 a counterfeiting scheme has been demonstrated for a class of invertible feature-based frequency domain invisible watermarking algorithms This counterfeiting scheme could be used to subvert ownership claims because the recovery of the digital signature from a watermarked image requires a comparison with an original The counterfeiting scheme works by first creating a counterfeit watermarked copy from the genuine watermarked copy by effectively inverting the genuine watermark This inversion creates a counterfeit of the original image A comparison of the decoded versions of both yield the owners (authorized) and the forged (inverted) signature This the technique of establishing legitimate ownership recovering the signature watermark by comparing a watermarked image with the original image breaks down It can be shown that both the legitimate signature and counterfeiters signature inhere in both the watermarked and counterfeit watermarked copies Thus while it may be demonstrated that at least one recipient has a counterfeit watermarked copy it cannot be determined which it is

Page | 19

9 Proposed Work

In traditional symmetric watermarking schemes the key used for watermark embedding must be available at the watermark detector This leads to a security problem if the detectors are implemented in consumer devices that are spread all over the world So asymmetric watermarking schemes also named public key digital watermarking schemes attract more and more attentions In such a public key watermarking system the private key is used for watermarking embedding and the public key is used only for watermarking detection The private key is kept for secret and the watermarks cannot easily be removed with public key

We are actually concentrating on studying public key watermarking techniques to evaluate and compare their performance in comparison to private key water marking techniques

Page | 20

10 RESEARCH DIRECTIONS

101 Study on Watermarking Algorithm

Digital watermarking technology processing contains two cores watermark embedding algorithm and detection algorithm Robustness imperceptibility invisibility and security of digital watermarking is generally the focus of the requirements

102 Study on Watermarking Theory

Although there are many published articles on watermarking the current watermarking technology canrsquot yet fill the actual requirements of most users The lack of standards interoperability problems as well as a suit of accurate and realistic requirements to watermarking system is still hinder the development of digital watermarking technology

There are still many problems to be resolved In order to be more widely used digital watermarking should establish a series of standards or agreements such as the standards of watermark embedding detection and certification Different watermarking algorithm has different compatibility and that is obviously not conducive to promoting the application of digital watermarking

103 Study on Watermark Attack

The relationship between watermark attack and watermarking algorithm is the same as spear and shield they restrict each other and promote each other as well To develop the technologies combined with cryptography authentication and digital signature is probably the direction of resistance development to various attacks

Page | 21

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

21 Examples of watermarking

Reporting or recording certain information about how the watermarked media is being transmitted accessed or used

EXAMPLE Broadcast monitoring equipment in use today detects watermarks in broadcasts and uses them to generate automatic reports about when where and how often specific content is being aired

EXAMPLE Web crawlers or media player devices could look for watermarks in content they crawl or play and then record information about where and when specific marked files are found or played

Providing information to the individual user

EXAMPLE A media player device upon reading a watermark in a file the user is accessing could display additional information that might interest the user such as metadata (information about the content) a special commercial offer or confirmation that the content is genuine and has not been altered Enabling or disabling access to particular capabilities or content

EXAMPLE An online service upon reading a watermark in content a user is trying to access could provide the user with an updated or authorized version of the content Triggering an investigation complaint or even legal measures concerning a particular user or distributor of watermarked content

EXAMPLE Watermarks embedded in infringing copies of copyrighted media content could enable copyright holders to trace the copies back to particular users or distributors and potentially to launch legal action

Page | 8

3 Requirements of watermarks

To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria

1 The watermark must be difficult or impossible to remove at least without visibly degrading the original image2 The watermark must survive image modifications that are common to typical image-processing applications (eg scaling dithering cropping compression)3 An invisible watermark should be imperceptible so as not to affect the experience of viewing the image and4 For some invisible watermarking applications watermarks should be readily detectable the proper authorities even if imperceptible to the average observer Such decidability without requiring the original un-watermarked image would be necessary for efficient recovery of property and subsequent prosecution

One can understand the challenge of researchers in this field since the above requirements compete each with the others The litmus test of a watermarking method would be that it is accepted and used on a large commercial scale and that it stands up in a court of law None of the digital techniques have yet to meet these tests

Page | 9

4 Properties of digital watermarking techniques

The most important properties of digital watermarking techniques are transparency robustness security capacity invertibility (reversibility) and complexity and possibility of verification Based on these parameters the algorithms can be evaluated if a specific algorithm has adequate properties and can be used for a certain application area

From we define the parameter as follows

Transparency - Relates to the properties of the human sensory A transparent watermark causes no artifacts or quality loss

Robustness - Describes whether the watermark can be reliably detected after media operations It is important to note that robustness does not include attacks on the embedding scheme that are based on the knowledge of the embedding algorithm or on the availability of the detector function Robustness means resistance to ldquoblindrdquo non-targeted modifications or common media operations For example the Stirmark or 2Mosaik tools attack the robustness of watermarking algorithms with geometrical distortions For manipulation recognition the watermark has to be fragile to detect altered media

Security - Describes whether the embedded watermarking information cannot be removed beyond reliable detection by targeted attacks based on a full knowledge of the embedding algorithm and the detector except the key and the knowledge of at least one watermarked data The concept of security includes procedural attacks such as the IBM attack or attacks based on a partial knowledge of the carrier modifications due to message embedding or embedding of templates The security aspect also includes the false positive detection rates

Capacity - Describes how many information bits can be embedded It addresses also the possibility of embedding multiple watermarks in one document in parallel

Invertibility - Describes the possibility to produce the original data during the watermark retrieval

Complexity - Describes the effort and time we need to embed and retrieve a watermark This parameter is essential if we have real time applications Another aspect addresses

Page | 10

whether the original data in the retrieval process or not We need to distinguish between non-blind and blind watermarking schemes

5 Types of Digital Watermarks

Watermarks and watermarking techniques can be divided into various categories in various ways The watermarks can be applied in spatial domain An alternative to spatial domain watermarking is frequency domain watermarking It has been pointed out that the frequency domain methods are more robust than the spatial domain techniques Different types of watermarks are shown in the Figure

Fig 8 Typology of digital watermarking

Watermarking techniques can be divided into two categories according to the type of working domain-

51 Spatial domain

Spatial watermarking can also be applied using color separation In this way the watermark appears in only one of the color bands This renders the watermark visibly subtle such that it is difficult to detect under regular viewing However the mark appears immediately when the colors are separated for printing This renders the document useless for the printer unless the

Page | 11

watermark can be removed from the color band This approach is used commercially for journalists to inspect digital pictures from a photo-stock house before buying unmarked versions

52 Frequency domain

Frequency domain (and other transform domains) by first applying a transform like the Fast Fourier Transform (FFT) In a similar manner to spatial domain watermarking the values of chosen frequencies can be altered from the original Since high frequencies will be lost by compression or scaling the watermark signal is applied to lower frequencies or better yet applied adaptively to frequencies that contain important information of the original picture Since watermarks applied to the frequency domain will be dispersed over the entirety of the spatial image upon inverse transformation this method is not as susceptible to defeat by cropping as the spatial technique However there is more a tradeoff here between invisibility and decodability since the watermark is in effect applied indiscriminately across the spatial image

Watermarking techniques can be divided into four categories according to the type of document to be watermarked as follows

53 Text WatermarkingThe process of embeddinghiding data in text document can be termed as ldquotext watermarkingrdquo This can be use to protect electronic documents paper documents are easy to copy and distribute electronically

54 Image WatermarkingThe process of embeddinghiding data in image document can be termed as ldquoimage watermarkingrdquo This process is done by visible water marking and invisible watermarking

55 Audio WatermarkingThe process of embedding information into audio can be termed as audio watermarking Can be achieved by inserting information about the distributor and the buyer A watermark embedded within an audio stream to identify its origination

56 Video WatermarkingVideo watermarking involves embedding cryptographic information derived from frames of digital video into the video itself Because the watermark is part of the video rather than part of the file format this technology works independently of the video file format or codec

According to the human perception the digital watermarks can be divided into three different types as follows

Page | 12

57 Visible watermark

Visible watermarks are especially useful for conveying an immediate claim of ownership The main advantage is that they virtually eliminate the commercial value of the document to a would-be thief without lessening the documents utility for legitimate authorized purposes A familiar example is in the video domain where a logo is placed in a corner of the screen image

58 Invisible-Robust watermark

The invisible-robust watermark is embedded in such a way that alternations madeto the pixel value are perceptually not noticed and it can be recovered only with appropriate decoding mechanism

59 Invisible-Fragile watermarkThe invisible-fragile watermark is embedded in such a way that any manipulation or modification of the image would alter or destroy the watermark

510 Dual watermark

Dual watermark is a combination of a visible and an invisible watermark In this type of water mark an invisible watermark is used as a backup for the visible watermark as clear from the following diagram

Figure Schematic representation of dual watermarking

From application point of view digital watermark could be as below

511 source based

Source-based watermark are desirable for ownership identification or authentication where a unique watermark identifying the owner is introduced to all the copies of a particular image being distributed A source-based watermark could be used for authentication and to determine whether a received image or other electronic data has been tampered with

Page | 13

512 destination based

The watermark could also be destination based where each distributed copy gets a unique watermark identifying the particular buyer The destination based watermark could be used to trace the buyer in the case of illegal reselling

6 Digital Watermarking Techniques

61 Text-based Watermarking

62 Image Watermarking

63 Audio Watermarking

64 Video Watermarking

61Text-Based Watermarking Techniques

A The text watermarking based on the fine-tuning of document structure

This is a technique which makes the text as a binary image it obtains watermark through fine-tuning the display style and it is imperceptibly by human visual The most classic algorithm is proposed by Brassil and Maxemchuk it gives many different ways to insert watermark in the PostScript document as follows

a) Line-shift encoding for the line space of a text file is uniform the coding method embeds a watermark by vertical shifting an entire line when the movement away from no more than 1 300 inches the human eye cannot easily perceive by analyzing the line spacing can determine whether it contains text watermark the process does not require the participation of the original text

b) word-shift encoding this coding method embeds watermark by level shifting some special words in a line When a word is shifted to right or left itrsquos adjacent words are not moving not moving words are as references location for the process of decoding Experience found that the human eye cannot identify the 1 150 inches below the level of displacement As the document is not a fixed word spacing so to determine whether it contains watermark needs the text of the original documents

c) Characteristics coding the coding method inserts a marker by changing the particular characteristics of a letter such as changing the height of a individual letter fonts etc The above-mentioned three kinds of coding methods are to use the spatial characteristics of text to embed the watermark These algorithm entirely depend on the text format (line-shift word-shift characteristics coding etc) there are many shortcomings such as not enough antiaggressive less robust not well hidden

Page | 14

Fig 9 Text water markingB The text watermark based on the not important content For a text when some of the expressions of the text occur Some minor changes there is no impact for understanding the document for this point the text watermark can be embedded Typical methods include inserting punctuation in sentences or inserting space at the end of a line For example we can store binary information by setting or not setting the comma in the two side-by-side words with and or or to connect

Specifically if the guns butter and flowers expresses the logic 1 then the guns butter and flower is logic0Weakness of such method that is the watermark information may be missing in the transmission process of application In addition the source text can not be arbitrary This method is not currently the main method of text watermarking

C The text watermark based on ldquoreplace the content of textrdquo The method is derived from information hiding technology It looks source text as the significance sequence instead of text images embedded in the course of the text is converted to vector with the same or similar meaning of the text of the secret process So watermark can be embedded by converting the source text into the same or similar meaning of hidden text

Usually in the English text many words have synonyms such as big and 1arge smart and clever and so on so we can elect these specific words of the text constitute a synonym replacement tables The word needs to be replaced said logic 0 the words that do not need to replace the logic 1So the secret data can be hidden in the text the number of hidden data relates to the synonym appear frequency in the text the method also applies to Chinese text The method of synonym replacement hide information by modifying the contents of the text it not only has better robustness but also do not need to rely on a specific document format However this approach requires source text cannot be arbitrary that is should contain a certain number of synonyms have been defined and in the process of extracting information needs the synonyms replace table

D The text watermark Based on natural language processing technology

Natural language processing is to in some specific applications automatically handling the text written in natural language such as machine translation information retrieval information

Page | 15

extraction data mining and intelligent search engines and so on after many years of development of the Natural language processing technology much experience and techniques have been accumulated such as word segmentation syntax analysis restatement eliminate the ambiguity of words and so on These are the foundation of The text watermark Based on natural language processing technology and compared to previous methods through the use of natural language processing technology embedded watermark informationmore secure reliable

Challenges

Marking copies uniquely

Making necessary for a recipient to provide personal information

Using encryption

Uses

Protect electronic documents

Paper documents are easy to copy and distribute electronically

62 Image Watermarking TechniquesIn image watermarking technique different type of technique is used as Digital Image ndash artificial resemblance of original object stored in form of binary numbers Image Watermarking ndash putting in some information that ensures your authentication of the document in the image itself Spatial domain algorithms- Two robust spatial-domain watermarking algorithms for image copyright protection are described as

The first one is robust against compression filtering and cropping Like all published crop-proof algorithms the one proposed here requires the original image for mark recovery Robustness against compression and filtering is obtained by using the JPEG algorithm to decide on mark location and magnitude robustness against cropping is achieved through a repetition code

The second watermarking algorithm uses visual components and is robust against compression filtering scaling and moderate rotations

The Discrete Cosine Transform (DCT)The discrete cosine transform (DCT) helps separate the image into parts (or spectral sub-bands) of differing importance (with respect to the images visual quality) The DCT is similar to the discrete Fourier transform it transforms a signal or image from the spatial domain to the frequency domain

Page | 16

Fig 10 DCT process diagramThe discrete cosine transform (DCT) is a technique for converting a signal into elementary frequency components It is widely used in image compression

Image Histogram

An image histogram is a type of histogram which acts as a graphical representation of the tonal distribution in a digital image It plots the number of pixels for each tonal value By looking at the histogram for a specific image a viewer will be able to judge the entire tonal distribution at a glance63 Audio Watermarking TechniquesIn audio watermarking technique different type of technique is used as

LSB watermarking - Least Significant Bit algorithm that embedding watermark into the least important part of the primary image and the watermark can be extracted from the primary image

The idea behind this watermarking technique is the following if you see you image as a matrix NxM (where N and M are the dimension of the image) you can represent the value of the pixel in the position (ij) as a binary number this binary can be then divided in all of its bit so that you will have a most significant bit (the one that contains quite a lot of information and a least significant bit that contains few information)

Quantisation watermarking - A new method for watermarking based on vector quantisation is proposed It is efficient for implementation with conventional techniques and simulation results show its robustness under a variety of attacks It also represents superiority over existing algorithms

Wavelet transform domain algorithms - The wavelet transform-domain least-mean square (WTDLMS) algorithm is known to have in general a faster convergence rate than the time-domain LMS algorithm and can find many applications in signal processing and communications areas However the computational complexity of the wavelet filter bank is relatively high In this work we show how to exploit the redundancy which exists in the computation of the wavelet coefficients between successive iterations so as to significantly reduce the computational load of the algorithm

Page | 17

7 Applications of Digital Watermarking

There is a wide variety of applications for watermarking The requirements of watermarking systems are always based on the application as for obvious reasons there is no ldquouniversalrdquo watermarking method Although it has to be robust in general different level of required robustness can be identified besides the specific characteristics of the problem which make the watermarking a suitable solution Several applications are listed below

Owner identification ndash similar to copyright protection to establish ownership of the content

Copy protection ndash also known as copy control to prevent people from making illegal copies of copyrighted content

Content authentication ndash to detect modifications of the content as a sign of invalid authentication

Fingerprinting ndash sometimes referred as transaction tracking or traitor tracking to trace back illegal duplication and distribution of the content

Broadcast monitoring ndash specifically for advertisements and in entertainment industries to monitor content being broadcasted as contracted and by the authorized source

Medical applications ndash known as invertible watermarking to provide both authentication and confidentiality in a reversible manner without affecting the medical image in any way

Page | 18

8 Limitations of digital watermarking

In January 1997 a counterfeiting scheme has been demonstrated for a class of invertible feature-based frequency domain invisible watermarking algorithms This counterfeiting scheme could be used to subvert ownership claims because the recovery of the digital signature from a watermarked image requires a comparison with an original The counterfeiting scheme works by first creating a counterfeit watermarked copy from the genuine watermarked copy by effectively inverting the genuine watermark This inversion creates a counterfeit of the original image A comparison of the decoded versions of both yield the owners (authorized) and the forged (inverted) signature This the technique of establishing legitimate ownership recovering the signature watermark by comparing a watermarked image with the original image breaks down It can be shown that both the legitimate signature and counterfeiters signature inhere in both the watermarked and counterfeit watermarked copies Thus while it may be demonstrated that at least one recipient has a counterfeit watermarked copy it cannot be determined which it is

Page | 19

9 Proposed Work

In traditional symmetric watermarking schemes the key used for watermark embedding must be available at the watermark detector This leads to a security problem if the detectors are implemented in consumer devices that are spread all over the world So asymmetric watermarking schemes also named public key digital watermarking schemes attract more and more attentions In such a public key watermarking system the private key is used for watermarking embedding and the public key is used only for watermarking detection The private key is kept for secret and the watermarks cannot easily be removed with public key

We are actually concentrating on studying public key watermarking techniques to evaluate and compare their performance in comparison to private key water marking techniques

Page | 20

10 RESEARCH DIRECTIONS

101 Study on Watermarking Algorithm

Digital watermarking technology processing contains two cores watermark embedding algorithm and detection algorithm Robustness imperceptibility invisibility and security of digital watermarking is generally the focus of the requirements

102 Study on Watermarking Theory

Although there are many published articles on watermarking the current watermarking technology canrsquot yet fill the actual requirements of most users The lack of standards interoperability problems as well as a suit of accurate and realistic requirements to watermarking system is still hinder the development of digital watermarking technology

There are still many problems to be resolved In order to be more widely used digital watermarking should establish a series of standards or agreements such as the standards of watermark embedding detection and certification Different watermarking algorithm has different compatibility and that is obviously not conducive to promoting the application of digital watermarking

103 Study on Watermark Attack

The relationship between watermark attack and watermarking algorithm is the same as spear and shield they restrict each other and promote each other as well To develop the technologies combined with cryptography authentication and digital signature is probably the direction of resistance development to various attacks

Page | 21

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

3 Requirements of watermarks

To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria

1 The watermark must be difficult or impossible to remove at least without visibly degrading the original image2 The watermark must survive image modifications that are common to typical image-processing applications (eg scaling dithering cropping compression)3 An invisible watermark should be imperceptible so as not to affect the experience of viewing the image and4 For some invisible watermarking applications watermarks should be readily detectable the proper authorities even if imperceptible to the average observer Such decidability without requiring the original un-watermarked image would be necessary for efficient recovery of property and subsequent prosecution

One can understand the challenge of researchers in this field since the above requirements compete each with the others The litmus test of a watermarking method would be that it is accepted and used on a large commercial scale and that it stands up in a court of law None of the digital techniques have yet to meet these tests

Page | 9

4 Properties of digital watermarking techniques

The most important properties of digital watermarking techniques are transparency robustness security capacity invertibility (reversibility) and complexity and possibility of verification Based on these parameters the algorithms can be evaluated if a specific algorithm has adequate properties and can be used for a certain application area

From we define the parameter as follows

Transparency - Relates to the properties of the human sensory A transparent watermark causes no artifacts or quality loss

Robustness - Describes whether the watermark can be reliably detected after media operations It is important to note that robustness does not include attacks on the embedding scheme that are based on the knowledge of the embedding algorithm or on the availability of the detector function Robustness means resistance to ldquoblindrdquo non-targeted modifications or common media operations For example the Stirmark or 2Mosaik tools attack the robustness of watermarking algorithms with geometrical distortions For manipulation recognition the watermark has to be fragile to detect altered media

Security - Describes whether the embedded watermarking information cannot be removed beyond reliable detection by targeted attacks based on a full knowledge of the embedding algorithm and the detector except the key and the knowledge of at least one watermarked data The concept of security includes procedural attacks such as the IBM attack or attacks based on a partial knowledge of the carrier modifications due to message embedding or embedding of templates The security aspect also includes the false positive detection rates

Capacity - Describes how many information bits can be embedded It addresses also the possibility of embedding multiple watermarks in one document in parallel

Invertibility - Describes the possibility to produce the original data during the watermark retrieval

Complexity - Describes the effort and time we need to embed and retrieve a watermark This parameter is essential if we have real time applications Another aspect addresses

Page | 10

whether the original data in the retrieval process or not We need to distinguish between non-blind and blind watermarking schemes

5 Types of Digital Watermarks

Watermarks and watermarking techniques can be divided into various categories in various ways The watermarks can be applied in spatial domain An alternative to spatial domain watermarking is frequency domain watermarking It has been pointed out that the frequency domain methods are more robust than the spatial domain techniques Different types of watermarks are shown in the Figure

Fig 8 Typology of digital watermarking

Watermarking techniques can be divided into two categories according to the type of working domain-

51 Spatial domain

Spatial watermarking can also be applied using color separation In this way the watermark appears in only one of the color bands This renders the watermark visibly subtle such that it is difficult to detect under regular viewing However the mark appears immediately when the colors are separated for printing This renders the document useless for the printer unless the

Page | 11

watermark can be removed from the color band This approach is used commercially for journalists to inspect digital pictures from a photo-stock house before buying unmarked versions

52 Frequency domain

Frequency domain (and other transform domains) by first applying a transform like the Fast Fourier Transform (FFT) In a similar manner to spatial domain watermarking the values of chosen frequencies can be altered from the original Since high frequencies will be lost by compression or scaling the watermark signal is applied to lower frequencies or better yet applied adaptively to frequencies that contain important information of the original picture Since watermarks applied to the frequency domain will be dispersed over the entirety of the spatial image upon inverse transformation this method is not as susceptible to defeat by cropping as the spatial technique However there is more a tradeoff here between invisibility and decodability since the watermark is in effect applied indiscriminately across the spatial image

Watermarking techniques can be divided into four categories according to the type of document to be watermarked as follows

53 Text WatermarkingThe process of embeddinghiding data in text document can be termed as ldquotext watermarkingrdquo This can be use to protect electronic documents paper documents are easy to copy and distribute electronically

54 Image WatermarkingThe process of embeddinghiding data in image document can be termed as ldquoimage watermarkingrdquo This process is done by visible water marking and invisible watermarking

55 Audio WatermarkingThe process of embedding information into audio can be termed as audio watermarking Can be achieved by inserting information about the distributor and the buyer A watermark embedded within an audio stream to identify its origination

56 Video WatermarkingVideo watermarking involves embedding cryptographic information derived from frames of digital video into the video itself Because the watermark is part of the video rather than part of the file format this technology works independently of the video file format or codec

According to the human perception the digital watermarks can be divided into three different types as follows

Page | 12

57 Visible watermark

Visible watermarks are especially useful for conveying an immediate claim of ownership The main advantage is that they virtually eliminate the commercial value of the document to a would-be thief without lessening the documents utility for legitimate authorized purposes A familiar example is in the video domain where a logo is placed in a corner of the screen image

58 Invisible-Robust watermark

The invisible-robust watermark is embedded in such a way that alternations madeto the pixel value are perceptually not noticed and it can be recovered only with appropriate decoding mechanism

59 Invisible-Fragile watermarkThe invisible-fragile watermark is embedded in such a way that any manipulation or modification of the image would alter or destroy the watermark

510 Dual watermark

Dual watermark is a combination of a visible and an invisible watermark In this type of water mark an invisible watermark is used as a backup for the visible watermark as clear from the following diagram

Figure Schematic representation of dual watermarking

From application point of view digital watermark could be as below

511 source based

Source-based watermark are desirable for ownership identification or authentication where a unique watermark identifying the owner is introduced to all the copies of a particular image being distributed A source-based watermark could be used for authentication and to determine whether a received image or other electronic data has been tampered with

Page | 13

512 destination based

The watermark could also be destination based where each distributed copy gets a unique watermark identifying the particular buyer The destination based watermark could be used to trace the buyer in the case of illegal reselling

6 Digital Watermarking Techniques

61 Text-based Watermarking

62 Image Watermarking

63 Audio Watermarking

64 Video Watermarking

61Text-Based Watermarking Techniques

A The text watermarking based on the fine-tuning of document structure

This is a technique which makes the text as a binary image it obtains watermark through fine-tuning the display style and it is imperceptibly by human visual The most classic algorithm is proposed by Brassil and Maxemchuk it gives many different ways to insert watermark in the PostScript document as follows

a) Line-shift encoding for the line space of a text file is uniform the coding method embeds a watermark by vertical shifting an entire line when the movement away from no more than 1 300 inches the human eye cannot easily perceive by analyzing the line spacing can determine whether it contains text watermark the process does not require the participation of the original text

b) word-shift encoding this coding method embeds watermark by level shifting some special words in a line When a word is shifted to right or left itrsquos adjacent words are not moving not moving words are as references location for the process of decoding Experience found that the human eye cannot identify the 1 150 inches below the level of displacement As the document is not a fixed word spacing so to determine whether it contains watermark needs the text of the original documents

c) Characteristics coding the coding method inserts a marker by changing the particular characteristics of a letter such as changing the height of a individual letter fonts etc The above-mentioned three kinds of coding methods are to use the spatial characteristics of text to embed the watermark These algorithm entirely depend on the text format (line-shift word-shift characteristics coding etc) there are many shortcomings such as not enough antiaggressive less robust not well hidden

Page | 14

Fig 9 Text water markingB The text watermark based on the not important content For a text when some of the expressions of the text occur Some minor changes there is no impact for understanding the document for this point the text watermark can be embedded Typical methods include inserting punctuation in sentences or inserting space at the end of a line For example we can store binary information by setting or not setting the comma in the two side-by-side words with and or or to connect

Specifically if the guns butter and flowers expresses the logic 1 then the guns butter and flower is logic0Weakness of such method that is the watermark information may be missing in the transmission process of application In addition the source text can not be arbitrary This method is not currently the main method of text watermarking

C The text watermark based on ldquoreplace the content of textrdquo The method is derived from information hiding technology It looks source text as the significance sequence instead of text images embedded in the course of the text is converted to vector with the same or similar meaning of the text of the secret process So watermark can be embedded by converting the source text into the same or similar meaning of hidden text

Usually in the English text many words have synonyms such as big and 1arge smart and clever and so on so we can elect these specific words of the text constitute a synonym replacement tables The word needs to be replaced said logic 0 the words that do not need to replace the logic 1So the secret data can be hidden in the text the number of hidden data relates to the synonym appear frequency in the text the method also applies to Chinese text The method of synonym replacement hide information by modifying the contents of the text it not only has better robustness but also do not need to rely on a specific document format However this approach requires source text cannot be arbitrary that is should contain a certain number of synonyms have been defined and in the process of extracting information needs the synonyms replace table

D The text watermark Based on natural language processing technology

Natural language processing is to in some specific applications automatically handling the text written in natural language such as machine translation information retrieval information

Page | 15

extraction data mining and intelligent search engines and so on after many years of development of the Natural language processing technology much experience and techniques have been accumulated such as word segmentation syntax analysis restatement eliminate the ambiguity of words and so on These are the foundation of The text watermark Based on natural language processing technology and compared to previous methods through the use of natural language processing technology embedded watermark informationmore secure reliable

Challenges

Marking copies uniquely

Making necessary for a recipient to provide personal information

Using encryption

Uses

Protect electronic documents

Paper documents are easy to copy and distribute electronically

62 Image Watermarking TechniquesIn image watermarking technique different type of technique is used as Digital Image ndash artificial resemblance of original object stored in form of binary numbers Image Watermarking ndash putting in some information that ensures your authentication of the document in the image itself Spatial domain algorithms- Two robust spatial-domain watermarking algorithms for image copyright protection are described as

The first one is robust against compression filtering and cropping Like all published crop-proof algorithms the one proposed here requires the original image for mark recovery Robustness against compression and filtering is obtained by using the JPEG algorithm to decide on mark location and magnitude robustness against cropping is achieved through a repetition code

The second watermarking algorithm uses visual components and is robust against compression filtering scaling and moderate rotations

The Discrete Cosine Transform (DCT)The discrete cosine transform (DCT) helps separate the image into parts (or spectral sub-bands) of differing importance (with respect to the images visual quality) The DCT is similar to the discrete Fourier transform it transforms a signal or image from the spatial domain to the frequency domain

Page | 16

Fig 10 DCT process diagramThe discrete cosine transform (DCT) is a technique for converting a signal into elementary frequency components It is widely used in image compression

Image Histogram

An image histogram is a type of histogram which acts as a graphical representation of the tonal distribution in a digital image It plots the number of pixels for each tonal value By looking at the histogram for a specific image a viewer will be able to judge the entire tonal distribution at a glance63 Audio Watermarking TechniquesIn audio watermarking technique different type of technique is used as

LSB watermarking - Least Significant Bit algorithm that embedding watermark into the least important part of the primary image and the watermark can be extracted from the primary image

The idea behind this watermarking technique is the following if you see you image as a matrix NxM (where N and M are the dimension of the image) you can represent the value of the pixel in the position (ij) as a binary number this binary can be then divided in all of its bit so that you will have a most significant bit (the one that contains quite a lot of information and a least significant bit that contains few information)

Quantisation watermarking - A new method for watermarking based on vector quantisation is proposed It is efficient for implementation with conventional techniques and simulation results show its robustness under a variety of attacks It also represents superiority over existing algorithms

Wavelet transform domain algorithms - The wavelet transform-domain least-mean square (WTDLMS) algorithm is known to have in general a faster convergence rate than the time-domain LMS algorithm and can find many applications in signal processing and communications areas However the computational complexity of the wavelet filter bank is relatively high In this work we show how to exploit the redundancy which exists in the computation of the wavelet coefficients between successive iterations so as to significantly reduce the computational load of the algorithm

Page | 17

7 Applications of Digital Watermarking

There is a wide variety of applications for watermarking The requirements of watermarking systems are always based on the application as for obvious reasons there is no ldquouniversalrdquo watermarking method Although it has to be robust in general different level of required robustness can be identified besides the specific characteristics of the problem which make the watermarking a suitable solution Several applications are listed below

Owner identification ndash similar to copyright protection to establish ownership of the content

Copy protection ndash also known as copy control to prevent people from making illegal copies of copyrighted content

Content authentication ndash to detect modifications of the content as a sign of invalid authentication

Fingerprinting ndash sometimes referred as transaction tracking or traitor tracking to trace back illegal duplication and distribution of the content

Broadcast monitoring ndash specifically for advertisements and in entertainment industries to monitor content being broadcasted as contracted and by the authorized source

Medical applications ndash known as invertible watermarking to provide both authentication and confidentiality in a reversible manner without affecting the medical image in any way

Page | 18

8 Limitations of digital watermarking

In January 1997 a counterfeiting scheme has been demonstrated for a class of invertible feature-based frequency domain invisible watermarking algorithms This counterfeiting scheme could be used to subvert ownership claims because the recovery of the digital signature from a watermarked image requires a comparison with an original The counterfeiting scheme works by first creating a counterfeit watermarked copy from the genuine watermarked copy by effectively inverting the genuine watermark This inversion creates a counterfeit of the original image A comparison of the decoded versions of both yield the owners (authorized) and the forged (inverted) signature This the technique of establishing legitimate ownership recovering the signature watermark by comparing a watermarked image with the original image breaks down It can be shown that both the legitimate signature and counterfeiters signature inhere in both the watermarked and counterfeit watermarked copies Thus while it may be demonstrated that at least one recipient has a counterfeit watermarked copy it cannot be determined which it is

Page | 19

9 Proposed Work

In traditional symmetric watermarking schemes the key used for watermark embedding must be available at the watermark detector This leads to a security problem if the detectors are implemented in consumer devices that are spread all over the world So asymmetric watermarking schemes also named public key digital watermarking schemes attract more and more attentions In such a public key watermarking system the private key is used for watermarking embedding and the public key is used only for watermarking detection The private key is kept for secret and the watermarks cannot easily be removed with public key

We are actually concentrating on studying public key watermarking techniques to evaluate and compare their performance in comparison to private key water marking techniques

Page | 20

10 RESEARCH DIRECTIONS

101 Study on Watermarking Algorithm

Digital watermarking technology processing contains two cores watermark embedding algorithm and detection algorithm Robustness imperceptibility invisibility and security of digital watermarking is generally the focus of the requirements

102 Study on Watermarking Theory

Although there are many published articles on watermarking the current watermarking technology canrsquot yet fill the actual requirements of most users The lack of standards interoperability problems as well as a suit of accurate and realistic requirements to watermarking system is still hinder the development of digital watermarking technology

There are still many problems to be resolved In order to be more widely used digital watermarking should establish a series of standards or agreements such as the standards of watermark embedding detection and certification Different watermarking algorithm has different compatibility and that is obviously not conducive to promoting the application of digital watermarking

103 Study on Watermark Attack

The relationship between watermark attack and watermarking algorithm is the same as spear and shield they restrict each other and promote each other as well To develop the technologies combined with cryptography authentication and digital signature is probably the direction of resistance development to various attacks

Page | 21

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

4 Properties of digital watermarking techniques

The most important properties of digital watermarking techniques are transparency robustness security capacity invertibility (reversibility) and complexity and possibility of verification Based on these parameters the algorithms can be evaluated if a specific algorithm has adequate properties and can be used for a certain application area

From we define the parameter as follows

Transparency - Relates to the properties of the human sensory A transparent watermark causes no artifacts or quality loss

Robustness - Describes whether the watermark can be reliably detected after media operations It is important to note that robustness does not include attacks on the embedding scheme that are based on the knowledge of the embedding algorithm or on the availability of the detector function Robustness means resistance to ldquoblindrdquo non-targeted modifications or common media operations For example the Stirmark or 2Mosaik tools attack the robustness of watermarking algorithms with geometrical distortions For manipulation recognition the watermark has to be fragile to detect altered media

Security - Describes whether the embedded watermarking information cannot be removed beyond reliable detection by targeted attacks based on a full knowledge of the embedding algorithm and the detector except the key and the knowledge of at least one watermarked data The concept of security includes procedural attacks such as the IBM attack or attacks based on a partial knowledge of the carrier modifications due to message embedding or embedding of templates The security aspect also includes the false positive detection rates

Capacity - Describes how many information bits can be embedded It addresses also the possibility of embedding multiple watermarks in one document in parallel

Invertibility - Describes the possibility to produce the original data during the watermark retrieval

Complexity - Describes the effort and time we need to embed and retrieve a watermark This parameter is essential if we have real time applications Another aspect addresses

Page | 10

whether the original data in the retrieval process or not We need to distinguish between non-blind and blind watermarking schemes

5 Types of Digital Watermarks

Watermarks and watermarking techniques can be divided into various categories in various ways The watermarks can be applied in spatial domain An alternative to spatial domain watermarking is frequency domain watermarking It has been pointed out that the frequency domain methods are more robust than the spatial domain techniques Different types of watermarks are shown in the Figure

Fig 8 Typology of digital watermarking

Watermarking techniques can be divided into two categories according to the type of working domain-

51 Spatial domain

Spatial watermarking can also be applied using color separation In this way the watermark appears in only one of the color bands This renders the watermark visibly subtle such that it is difficult to detect under regular viewing However the mark appears immediately when the colors are separated for printing This renders the document useless for the printer unless the

Page | 11

watermark can be removed from the color band This approach is used commercially for journalists to inspect digital pictures from a photo-stock house before buying unmarked versions

52 Frequency domain

Frequency domain (and other transform domains) by first applying a transform like the Fast Fourier Transform (FFT) In a similar manner to spatial domain watermarking the values of chosen frequencies can be altered from the original Since high frequencies will be lost by compression or scaling the watermark signal is applied to lower frequencies or better yet applied adaptively to frequencies that contain important information of the original picture Since watermarks applied to the frequency domain will be dispersed over the entirety of the spatial image upon inverse transformation this method is not as susceptible to defeat by cropping as the spatial technique However there is more a tradeoff here between invisibility and decodability since the watermark is in effect applied indiscriminately across the spatial image

Watermarking techniques can be divided into four categories according to the type of document to be watermarked as follows

53 Text WatermarkingThe process of embeddinghiding data in text document can be termed as ldquotext watermarkingrdquo This can be use to protect electronic documents paper documents are easy to copy and distribute electronically

54 Image WatermarkingThe process of embeddinghiding data in image document can be termed as ldquoimage watermarkingrdquo This process is done by visible water marking and invisible watermarking

55 Audio WatermarkingThe process of embedding information into audio can be termed as audio watermarking Can be achieved by inserting information about the distributor and the buyer A watermark embedded within an audio stream to identify its origination

56 Video WatermarkingVideo watermarking involves embedding cryptographic information derived from frames of digital video into the video itself Because the watermark is part of the video rather than part of the file format this technology works independently of the video file format or codec

According to the human perception the digital watermarks can be divided into three different types as follows

Page | 12

57 Visible watermark

Visible watermarks are especially useful for conveying an immediate claim of ownership The main advantage is that they virtually eliminate the commercial value of the document to a would-be thief without lessening the documents utility for legitimate authorized purposes A familiar example is in the video domain where a logo is placed in a corner of the screen image

58 Invisible-Robust watermark

The invisible-robust watermark is embedded in such a way that alternations madeto the pixel value are perceptually not noticed and it can be recovered only with appropriate decoding mechanism

59 Invisible-Fragile watermarkThe invisible-fragile watermark is embedded in such a way that any manipulation or modification of the image would alter or destroy the watermark

510 Dual watermark

Dual watermark is a combination of a visible and an invisible watermark In this type of water mark an invisible watermark is used as a backup for the visible watermark as clear from the following diagram

Figure Schematic representation of dual watermarking

From application point of view digital watermark could be as below

511 source based

Source-based watermark are desirable for ownership identification or authentication where a unique watermark identifying the owner is introduced to all the copies of a particular image being distributed A source-based watermark could be used for authentication and to determine whether a received image or other electronic data has been tampered with

Page | 13

512 destination based

The watermark could also be destination based where each distributed copy gets a unique watermark identifying the particular buyer The destination based watermark could be used to trace the buyer in the case of illegal reselling

6 Digital Watermarking Techniques

61 Text-based Watermarking

62 Image Watermarking

63 Audio Watermarking

64 Video Watermarking

61Text-Based Watermarking Techniques

A The text watermarking based on the fine-tuning of document structure

This is a technique which makes the text as a binary image it obtains watermark through fine-tuning the display style and it is imperceptibly by human visual The most classic algorithm is proposed by Brassil and Maxemchuk it gives many different ways to insert watermark in the PostScript document as follows

a) Line-shift encoding for the line space of a text file is uniform the coding method embeds a watermark by vertical shifting an entire line when the movement away from no more than 1 300 inches the human eye cannot easily perceive by analyzing the line spacing can determine whether it contains text watermark the process does not require the participation of the original text

b) word-shift encoding this coding method embeds watermark by level shifting some special words in a line When a word is shifted to right or left itrsquos adjacent words are not moving not moving words are as references location for the process of decoding Experience found that the human eye cannot identify the 1 150 inches below the level of displacement As the document is not a fixed word spacing so to determine whether it contains watermark needs the text of the original documents

c) Characteristics coding the coding method inserts a marker by changing the particular characteristics of a letter such as changing the height of a individual letter fonts etc The above-mentioned three kinds of coding methods are to use the spatial characteristics of text to embed the watermark These algorithm entirely depend on the text format (line-shift word-shift characteristics coding etc) there are many shortcomings such as not enough antiaggressive less robust not well hidden

Page | 14

Fig 9 Text water markingB The text watermark based on the not important content For a text when some of the expressions of the text occur Some minor changes there is no impact for understanding the document for this point the text watermark can be embedded Typical methods include inserting punctuation in sentences or inserting space at the end of a line For example we can store binary information by setting or not setting the comma in the two side-by-side words with and or or to connect

Specifically if the guns butter and flowers expresses the logic 1 then the guns butter and flower is logic0Weakness of such method that is the watermark information may be missing in the transmission process of application In addition the source text can not be arbitrary This method is not currently the main method of text watermarking

C The text watermark based on ldquoreplace the content of textrdquo The method is derived from information hiding technology It looks source text as the significance sequence instead of text images embedded in the course of the text is converted to vector with the same or similar meaning of the text of the secret process So watermark can be embedded by converting the source text into the same or similar meaning of hidden text

Usually in the English text many words have synonyms such as big and 1arge smart and clever and so on so we can elect these specific words of the text constitute a synonym replacement tables The word needs to be replaced said logic 0 the words that do not need to replace the logic 1So the secret data can be hidden in the text the number of hidden data relates to the synonym appear frequency in the text the method also applies to Chinese text The method of synonym replacement hide information by modifying the contents of the text it not only has better robustness but also do not need to rely on a specific document format However this approach requires source text cannot be arbitrary that is should contain a certain number of synonyms have been defined and in the process of extracting information needs the synonyms replace table

D The text watermark Based on natural language processing technology

Natural language processing is to in some specific applications automatically handling the text written in natural language such as machine translation information retrieval information

Page | 15

extraction data mining and intelligent search engines and so on after many years of development of the Natural language processing technology much experience and techniques have been accumulated such as word segmentation syntax analysis restatement eliminate the ambiguity of words and so on These are the foundation of The text watermark Based on natural language processing technology and compared to previous methods through the use of natural language processing technology embedded watermark informationmore secure reliable

Challenges

Marking copies uniquely

Making necessary for a recipient to provide personal information

Using encryption

Uses

Protect electronic documents

Paper documents are easy to copy and distribute electronically

62 Image Watermarking TechniquesIn image watermarking technique different type of technique is used as Digital Image ndash artificial resemblance of original object stored in form of binary numbers Image Watermarking ndash putting in some information that ensures your authentication of the document in the image itself Spatial domain algorithms- Two robust spatial-domain watermarking algorithms for image copyright protection are described as

The first one is robust against compression filtering and cropping Like all published crop-proof algorithms the one proposed here requires the original image for mark recovery Robustness against compression and filtering is obtained by using the JPEG algorithm to decide on mark location and magnitude robustness against cropping is achieved through a repetition code

The second watermarking algorithm uses visual components and is robust against compression filtering scaling and moderate rotations

The Discrete Cosine Transform (DCT)The discrete cosine transform (DCT) helps separate the image into parts (or spectral sub-bands) of differing importance (with respect to the images visual quality) The DCT is similar to the discrete Fourier transform it transforms a signal or image from the spatial domain to the frequency domain

Page | 16

Fig 10 DCT process diagramThe discrete cosine transform (DCT) is a technique for converting a signal into elementary frequency components It is widely used in image compression

Image Histogram

An image histogram is a type of histogram which acts as a graphical representation of the tonal distribution in a digital image It plots the number of pixels for each tonal value By looking at the histogram for a specific image a viewer will be able to judge the entire tonal distribution at a glance63 Audio Watermarking TechniquesIn audio watermarking technique different type of technique is used as

LSB watermarking - Least Significant Bit algorithm that embedding watermark into the least important part of the primary image and the watermark can be extracted from the primary image

The idea behind this watermarking technique is the following if you see you image as a matrix NxM (where N and M are the dimension of the image) you can represent the value of the pixel in the position (ij) as a binary number this binary can be then divided in all of its bit so that you will have a most significant bit (the one that contains quite a lot of information and a least significant bit that contains few information)

Quantisation watermarking - A new method for watermarking based on vector quantisation is proposed It is efficient for implementation with conventional techniques and simulation results show its robustness under a variety of attacks It also represents superiority over existing algorithms

Wavelet transform domain algorithms - The wavelet transform-domain least-mean square (WTDLMS) algorithm is known to have in general a faster convergence rate than the time-domain LMS algorithm and can find many applications in signal processing and communications areas However the computational complexity of the wavelet filter bank is relatively high In this work we show how to exploit the redundancy which exists in the computation of the wavelet coefficients between successive iterations so as to significantly reduce the computational load of the algorithm

Page | 17

7 Applications of Digital Watermarking

There is a wide variety of applications for watermarking The requirements of watermarking systems are always based on the application as for obvious reasons there is no ldquouniversalrdquo watermarking method Although it has to be robust in general different level of required robustness can be identified besides the specific characteristics of the problem which make the watermarking a suitable solution Several applications are listed below

Owner identification ndash similar to copyright protection to establish ownership of the content

Copy protection ndash also known as copy control to prevent people from making illegal copies of copyrighted content

Content authentication ndash to detect modifications of the content as a sign of invalid authentication

Fingerprinting ndash sometimes referred as transaction tracking or traitor tracking to trace back illegal duplication and distribution of the content

Broadcast monitoring ndash specifically for advertisements and in entertainment industries to monitor content being broadcasted as contracted and by the authorized source

Medical applications ndash known as invertible watermarking to provide both authentication and confidentiality in a reversible manner without affecting the medical image in any way

Page | 18

8 Limitations of digital watermarking

In January 1997 a counterfeiting scheme has been demonstrated for a class of invertible feature-based frequency domain invisible watermarking algorithms This counterfeiting scheme could be used to subvert ownership claims because the recovery of the digital signature from a watermarked image requires a comparison with an original The counterfeiting scheme works by first creating a counterfeit watermarked copy from the genuine watermarked copy by effectively inverting the genuine watermark This inversion creates a counterfeit of the original image A comparison of the decoded versions of both yield the owners (authorized) and the forged (inverted) signature This the technique of establishing legitimate ownership recovering the signature watermark by comparing a watermarked image with the original image breaks down It can be shown that both the legitimate signature and counterfeiters signature inhere in both the watermarked and counterfeit watermarked copies Thus while it may be demonstrated that at least one recipient has a counterfeit watermarked copy it cannot be determined which it is

Page | 19

9 Proposed Work

In traditional symmetric watermarking schemes the key used for watermark embedding must be available at the watermark detector This leads to a security problem if the detectors are implemented in consumer devices that are spread all over the world So asymmetric watermarking schemes also named public key digital watermarking schemes attract more and more attentions In such a public key watermarking system the private key is used for watermarking embedding and the public key is used only for watermarking detection The private key is kept for secret and the watermarks cannot easily be removed with public key

We are actually concentrating on studying public key watermarking techniques to evaluate and compare their performance in comparison to private key water marking techniques

Page | 20

10 RESEARCH DIRECTIONS

101 Study on Watermarking Algorithm

Digital watermarking technology processing contains two cores watermark embedding algorithm and detection algorithm Robustness imperceptibility invisibility and security of digital watermarking is generally the focus of the requirements

102 Study on Watermarking Theory

Although there are many published articles on watermarking the current watermarking technology canrsquot yet fill the actual requirements of most users The lack of standards interoperability problems as well as a suit of accurate and realistic requirements to watermarking system is still hinder the development of digital watermarking technology

There are still many problems to be resolved In order to be more widely used digital watermarking should establish a series of standards or agreements such as the standards of watermark embedding detection and certification Different watermarking algorithm has different compatibility and that is obviously not conducive to promoting the application of digital watermarking

103 Study on Watermark Attack

The relationship between watermark attack and watermarking algorithm is the same as spear and shield they restrict each other and promote each other as well To develop the technologies combined with cryptography authentication and digital signature is probably the direction of resistance development to various attacks

Page | 21

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

whether the original data in the retrieval process or not We need to distinguish between non-blind and blind watermarking schemes

5 Types of Digital Watermarks

Watermarks and watermarking techniques can be divided into various categories in various ways The watermarks can be applied in spatial domain An alternative to spatial domain watermarking is frequency domain watermarking It has been pointed out that the frequency domain methods are more robust than the spatial domain techniques Different types of watermarks are shown in the Figure

Fig 8 Typology of digital watermarking

Watermarking techniques can be divided into two categories according to the type of working domain-

51 Spatial domain

Spatial watermarking can also be applied using color separation In this way the watermark appears in only one of the color bands This renders the watermark visibly subtle such that it is difficult to detect under regular viewing However the mark appears immediately when the colors are separated for printing This renders the document useless for the printer unless the

Page | 11

watermark can be removed from the color band This approach is used commercially for journalists to inspect digital pictures from a photo-stock house before buying unmarked versions

52 Frequency domain

Frequency domain (and other transform domains) by first applying a transform like the Fast Fourier Transform (FFT) In a similar manner to spatial domain watermarking the values of chosen frequencies can be altered from the original Since high frequencies will be lost by compression or scaling the watermark signal is applied to lower frequencies or better yet applied adaptively to frequencies that contain important information of the original picture Since watermarks applied to the frequency domain will be dispersed over the entirety of the spatial image upon inverse transformation this method is not as susceptible to defeat by cropping as the spatial technique However there is more a tradeoff here between invisibility and decodability since the watermark is in effect applied indiscriminately across the spatial image

Watermarking techniques can be divided into four categories according to the type of document to be watermarked as follows

53 Text WatermarkingThe process of embeddinghiding data in text document can be termed as ldquotext watermarkingrdquo This can be use to protect electronic documents paper documents are easy to copy and distribute electronically

54 Image WatermarkingThe process of embeddinghiding data in image document can be termed as ldquoimage watermarkingrdquo This process is done by visible water marking and invisible watermarking

55 Audio WatermarkingThe process of embedding information into audio can be termed as audio watermarking Can be achieved by inserting information about the distributor and the buyer A watermark embedded within an audio stream to identify its origination

56 Video WatermarkingVideo watermarking involves embedding cryptographic information derived from frames of digital video into the video itself Because the watermark is part of the video rather than part of the file format this technology works independently of the video file format or codec

According to the human perception the digital watermarks can be divided into three different types as follows

Page | 12

57 Visible watermark

Visible watermarks are especially useful for conveying an immediate claim of ownership The main advantage is that they virtually eliminate the commercial value of the document to a would-be thief without lessening the documents utility for legitimate authorized purposes A familiar example is in the video domain where a logo is placed in a corner of the screen image

58 Invisible-Robust watermark

The invisible-robust watermark is embedded in such a way that alternations madeto the pixel value are perceptually not noticed and it can be recovered only with appropriate decoding mechanism

59 Invisible-Fragile watermarkThe invisible-fragile watermark is embedded in such a way that any manipulation or modification of the image would alter or destroy the watermark

510 Dual watermark

Dual watermark is a combination of a visible and an invisible watermark In this type of water mark an invisible watermark is used as a backup for the visible watermark as clear from the following diagram

Figure Schematic representation of dual watermarking

From application point of view digital watermark could be as below

511 source based

Source-based watermark are desirable for ownership identification or authentication where a unique watermark identifying the owner is introduced to all the copies of a particular image being distributed A source-based watermark could be used for authentication and to determine whether a received image or other electronic data has been tampered with

Page | 13

512 destination based

The watermark could also be destination based where each distributed copy gets a unique watermark identifying the particular buyer The destination based watermark could be used to trace the buyer in the case of illegal reselling

6 Digital Watermarking Techniques

61 Text-based Watermarking

62 Image Watermarking

63 Audio Watermarking

64 Video Watermarking

61Text-Based Watermarking Techniques

A The text watermarking based on the fine-tuning of document structure

This is a technique which makes the text as a binary image it obtains watermark through fine-tuning the display style and it is imperceptibly by human visual The most classic algorithm is proposed by Brassil and Maxemchuk it gives many different ways to insert watermark in the PostScript document as follows

a) Line-shift encoding for the line space of a text file is uniform the coding method embeds a watermark by vertical shifting an entire line when the movement away from no more than 1 300 inches the human eye cannot easily perceive by analyzing the line spacing can determine whether it contains text watermark the process does not require the participation of the original text

b) word-shift encoding this coding method embeds watermark by level shifting some special words in a line When a word is shifted to right or left itrsquos adjacent words are not moving not moving words are as references location for the process of decoding Experience found that the human eye cannot identify the 1 150 inches below the level of displacement As the document is not a fixed word spacing so to determine whether it contains watermark needs the text of the original documents

c) Characteristics coding the coding method inserts a marker by changing the particular characteristics of a letter such as changing the height of a individual letter fonts etc The above-mentioned three kinds of coding methods are to use the spatial characteristics of text to embed the watermark These algorithm entirely depend on the text format (line-shift word-shift characteristics coding etc) there are many shortcomings such as not enough antiaggressive less robust not well hidden

Page | 14

Fig 9 Text water markingB The text watermark based on the not important content For a text when some of the expressions of the text occur Some minor changes there is no impact for understanding the document for this point the text watermark can be embedded Typical methods include inserting punctuation in sentences or inserting space at the end of a line For example we can store binary information by setting or not setting the comma in the two side-by-side words with and or or to connect

Specifically if the guns butter and flowers expresses the logic 1 then the guns butter and flower is logic0Weakness of such method that is the watermark information may be missing in the transmission process of application In addition the source text can not be arbitrary This method is not currently the main method of text watermarking

C The text watermark based on ldquoreplace the content of textrdquo The method is derived from information hiding technology It looks source text as the significance sequence instead of text images embedded in the course of the text is converted to vector with the same or similar meaning of the text of the secret process So watermark can be embedded by converting the source text into the same or similar meaning of hidden text

Usually in the English text many words have synonyms such as big and 1arge smart and clever and so on so we can elect these specific words of the text constitute a synonym replacement tables The word needs to be replaced said logic 0 the words that do not need to replace the logic 1So the secret data can be hidden in the text the number of hidden data relates to the synonym appear frequency in the text the method also applies to Chinese text The method of synonym replacement hide information by modifying the contents of the text it not only has better robustness but also do not need to rely on a specific document format However this approach requires source text cannot be arbitrary that is should contain a certain number of synonyms have been defined and in the process of extracting information needs the synonyms replace table

D The text watermark Based on natural language processing technology

Natural language processing is to in some specific applications automatically handling the text written in natural language such as machine translation information retrieval information

Page | 15

extraction data mining and intelligent search engines and so on after many years of development of the Natural language processing technology much experience and techniques have been accumulated such as word segmentation syntax analysis restatement eliminate the ambiguity of words and so on These are the foundation of The text watermark Based on natural language processing technology and compared to previous methods through the use of natural language processing technology embedded watermark informationmore secure reliable

Challenges

Marking copies uniquely

Making necessary for a recipient to provide personal information

Using encryption

Uses

Protect electronic documents

Paper documents are easy to copy and distribute electronically

62 Image Watermarking TechniquesIn image watermarking technique different type of technique is used as Digital Image ndash artificial resemblance of original object stored in form of binary numbers Image Watermarking ndash putting in some information that ensures your authentication of the document in the image itself Spatial domain algorithms- Two robust spatial-domain watermarking algorithms for image copyright protection are described as

The first one is robust against compression filtering and cropping Like all published crop-proof algorithms the one proposed here requires the original image for mark recovery Robustness against compression and filtering is obtained by using the JPEG algorithm to decide on mark location and magnitude robustness against cropping is achieved through a repetition code

The second watermarking algorithm uses visual components and is robust against compression filtering scaling and moderate rotations

The Discrete Cosine Transform (DCT)The discrete cosine transform (DCT) helps separate the image into parts (or spectral sub-bands) of differing importance (with respect to the images visual quality) The DCT is similar to the discrete Fourier transform it transforms a signal or image from the spatial domain to the frequency domain

Page | 16

Fig 10 DCT process diagramThe discrete cosine transform (DCT) is a technique for converting a signal into elementary frequency components It is widely used in image compression

Image Histogram

An image histogram is a type of histogram which acts as a graphical representation of the tonal distribution in a digital image It plots the number of pixels for each tonal value By looking at the histogram for a specific image a viewer will be able to judge the entire tonal distribution at a glance63 Audio Watermarking TechniquesIn audio watermarking technique different type of technique is used as

LSB watermarking - Least Significant Bit algorithm that embedding watermark into the least important part of the primary image and the watermark can be extracted from the primary image

The idea behind this watermarking technique is the following if you see you image as a matrix NxM (where N and M are the dimension of the image) you can represent the value of the pixel in the position (ij) as a binary number this binary can be then divided in all of its bit so that you will have a most significant bit (the one that contains quite a lot of information and a least significant bit that contains few information)

Quantisation watermarking - A new method for watermarking based on vector quantisation is proposed It is efficient for implementation with conventional techniques and simulation results show its robustness under a variety of attacks It also represents superiority over existing algorithms

Wavelet transform domain algorithms - The wavelet transform-domain least-mean square (WTDLMS) algorithm is known to have in general a faster convergence rate than the time-domain LMS algorithm and can find many applications in signal processing and communications areas However the computational complexity of the wavelet filter bank is relatively high In this work we show how to exploit the redundancy which exists in the computation of the wavelet coefficients between successive iterations so as to significantly reduce the computational load of the algorithm

Page | 17

7 Applications of Digital Watermarking

There is a wide variety of applications for watermarking The requirements of watermarking systems are always based on the application as for obvious reasons there is no ldquouniversalrdquo watermarking method Although it has to be robust in general different level of required robustness can be identified besides the specific characteristics of the problem which make the watermarking a suitable solution Several applications are listed below

Owner identification ndash similar to copyright protection to establish ownership of the content

Copy protection ndash also known as copy control to prevent people from making illegal copies of copyrighted content

Content authentication ndash to detect modifications of the content as a sign of invalid authentication

Fingerprinting ndash sometimes referred as transaction tracking or traitor tracking to trace back illegal duplication and distribution of the content

Broadcast monitoring ndash specifically for advertisements and in entertainment industries to monitor content being broadcasted as contracted and by the authorized source

Medical applications ndash known as invertible watermarking to provide both authentication and confidentiality in a reversible manner without affecting the medical image in any way

Page | 18

8 Limitations of digital watermarking

In January 1997 a counterfeiting scheme has been demonstrated for a class of invertible feature-based frequency domain invisible watermarking algorithms This counterfeiting scheme could be used to subvert ownership claims because the recovery of the digital signature from a watermarked image requires a comparison with an original The counterfeiting scheme works by first creating a counterfeit watermarked copy from the genuine watermarked copy by effectively inverting the genuine watermark This inversion creates a counterfeit of the original image A comparison of the decoded versions of both yield the owners (authorized) and the forged (inverted) signature This the technique of establishing legitimate ownership recovering the signature watermark by comparing a watermarked image with the original image breaks down It can be shown that both the legitimate signature and counterfeiters signature inhere in both the watermarked and counterfeit watermarked copies Thus while it may be demonstrated that at least one recipient has a counterfeit watermarked copy it cannot be determined which it is

Page | 19

9 Proposed Work

In traditional symmetric watermarking schemes the key used for watermark embedding must be available at the watermark detector This leads to a security problem if the detectors are implemented in consumer devices that are spread all over the world So asymmetric watermarking schemes also named public key digital watermarking schemes attract more and more attentions In such a public key watermarking system the private key is used for watermarking embedding and the public key is used only for watermarking detection The private key is kept for secret and the watermarks cannot easily be removed with public key

We are actually concentrating on studying public key watermarking techniques to evaluate and compare their performance in comparison to private key water marking techniques

Page | 20

10 RESEARCH DIRECTIONS

101 Study on Watermarking Algorithm

Digital watermarking technology processing contains two cores watermark embedding algorithm and detection algorithm Robustness imperceptibility invisibility and security of digital watermarking is generally the focus of the requirements

102 Study on Watermarking Theory

Although there are many published articles on watermarking the current watermarking technology canrsquot yet fill the actual requirements of most users The lack of standards interoperability problems as well as a suit of accurate and realistic requirements to watermarking system is still hinder the development of digital watermarking technology

There are still many problems to be resolved In order to be more widely used digital watermarking should establish a series of standards or agreements such as the standards of watermark embedding detection and certification Different watermarking algorithm has different compatibility and that is obviously not conducive to promoting the application of digital watermarking

103 Study on Watermark Attack

The relationship between watermark attack and watermarking algorithm is the same as spear and shield they restrict each other and promote each other as well To develop the technologies combined with cryptography authentication and digital signature is probably the direction of resistance development to various attacks

Page | 21

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

watermark can be removed from the color band This approach is used commercially for journalists to inspect digital pictures from a photo-stock house before buying unmarked versions

52 Frequency domain

Frequency domain (and other transform domains) by first applying a transform like the Fast Fourier Transform (FFT) In a similar manner to spatial domain watermarking the values of chosen frequencies can be altered from the original Since high frequencies will be lost by compression or scaling the watermark signal is applied to lower frequencies or better yet applied adaptively to frequencies that contain important information of the original picture Since watermarks applied to the frequency domain will be dispersed over the entirety of the spatial image upon inverse transformation this method is not as susceptible to defeat by cropping as the spatial technique However there is more a tradeoff here between invisibility and decodability since the watermark is in effect applied indiscriminately across the spatial image

Watermarking techniques can be divided into four categories according to the type of document to be watermarked as follows

53 Text WatermarkingThe process of embeddinghiding data in text document can be termed as ldquotext watermarkingrdquo This can be use to protect electronic documents paper documents are easy to copy and distribute electronically

54 Image WatermarkingThe process of embeddinghiding data in image document can be termed as ldquoimage watermarkingrdquo This process is done by visible water marking and invisible watermarking

55 Audio WatermarkingThe process of embedding information into audio can be termed as audio watermarking Can be achieved by inserting information about the distributor and the buyer A watermark embedded within an audio stream to identify its origination

56 Video WatermarkingVideo watermarking involves embedding cryptographic information derived from frames of digital video into the video itself Because the watermark is part of the video rather than part of the file format this technology works independently of the video file format or codec

According to the human perception the digital watermarks can be divided into three different types as follows

Page | 12

57 Visible watermark

Visible watermarks are especially useful for conveying an immediate claim of ownership The main advantage is that they virtually eliminate the commercial value of the document to a would-be thief without lessening the documents utility for legitimate authorized purposes A familiar example is in the video domain where a logo is placed in a corner of the screen image

58 Invisible-Robust watermark

The invisible-robust watermark is embedded in such a way that alternations madeto the pixel value are perceptually not noticed and it can be recovered only with appropriate decoding mechanism

59 Invisible-Fragile watermarkThe invisible-fragile watermark is embedded in such a way that any manipulation or modification of the image would alter or destroy the watermark

510 Dual watermark

Dual watermark is a combination of a visible and an invisible watermark In this type of water mark an invisible watermark is used as a backup for the visible watermark as clear from the following diagram

Figure Schematic representation of dual watermarking

From application point of view digital watermark could be as below

511 source based

Source-based watermark are desirable for ownership identification or authentication where a unique watermark identifying the owner is introduced to all the copies of a particular image being distributed A source-based watermark could be used for authentication and to determine whether a received image or other electronic data has been tampered with

Page | 13

512 destination based

The watermark could also be destination based where each distributed copy gets a unique watermark identifying the particular buyer The destination based watermark could be used to trace the buyer in the case of illegal reselling

6 Digital Watermarking Techniques

61 Text-based Watermarking

62 Image Watermarking

63 Audio Watermarking

64 Video Watermarking

61Text-Based Watermarking Techniques

A The text watermarking based on the fine-tuning of document structure

This is a technique which makes the text as a binary image it obtains watermark through fine-tuning the display style and it is imperceptibly by human visual The most classic algorithm is proposed by Brassil and Maxemchuk it gives many different ways to insert watermark in the PostScript document as follows

a) Line-shift encoding for the line space of a text file is uniform the coding method embeds a watermark by vertical shifting an entire line when the movement away from no more than 1 300 inches the human eye cannot easily perceive by analyzing the line spacing can determine whether it contains text watermark the process does not require the participation of the original text

b) word-shift encoding this coding method embeds watermark by level shifting some special words in a line When a word is shifted to right or left itrsquos adjacent words are not moving not moving words are as references location for the process of decoding Experience found that the human eye cannot identify the 1 150 inches below the level of displacement As the document is not a fixed word spacing so to determine whether it contains watermark needs the text of the original documents

c) Characteristics coding the coding method inserts a marker by changing the particular characteristics of a letter such as changing the height of a individual letter fonts etc The above-mentioned three kinds of coding methods are to use the spatial characteristics of text to embed the watermark These algorithm entirely depend on the text format (line-shift word-shift characteristics coding etc) there are many shortcomings such as not enough antiaggressive less robust not well hidden

Page | 14

Fig 9 Text water markingB The text watermark based on the not important content For a text when some of the expressions of the text occur Some minor changes there is no impact for understanding the document for this point the text watermark can be embedded Typical methods include inserting punctuation in sentences or inserting space at the end of a line For example we can store binary information by setting or not setting the comma in the two side-by-side words with and or or to connect

Specifically if the guns butter and flowers expresses the logic 1 then the guns butter and flower is logic0Weakness of such method that is the watermark information may be missing in the transmission process of application In addition the source text can not be arbitrary This method is not currently the main method of text watermarking

C The text watermark based on ldquoreplace the content of textrdquo The method is derived from information hiding technology It looks source text as the significance sequence instead of text images embedded in the course of the text is converted to vector with the same or similar meaning of the text of the secret process So watermark can be embedded by converting the source text into the same or similar meaning of hidden text

Usually in the English text many words have synonyms such as big and 1arge smart and clever and so on so we can elect these specific words of the text constitute a synonym replacement tables The word needs to be replaced said logic 0 the words that do not need to replace the logic 1So the secret data can be hidden in the text the number of hidden data relates to the synonym appear frequency in the text the method also applies to Chinese text The method of synonym replacement hide information by modifying the contents of the text it not only has better robustness but also do not need to rely on a specific document format However this approach requires source text cannot be arbitrary that is should contain a certain number of synonyms have been defined and in the process of extracting information needs the synonyms replace table

D The text watermark Based on natural language processing technology

Natural language processing is to in some specific applications automatically handling the text written in natural language such as machine translation information retrieval information

Page | 15

extraction data mining and intelligent search engines and so on after many years of development of the Natural language processing technology much experience and techniques have been accumulated such as word segmentation syntax analysis restatement eliminate the ambiguity of words and so on These are the foundation of The text watermark Based on natural language processing technology and compared to previous methods through the use of natural language processing technology embedded watermark informationmore secure reliable

Challenges

Marking copies uniquely

Making necessary for a recipient to provide personal information

Using encryption

Uses

Protect electronic documents

Paper documents are easy to copy and distribute electronically

62 Image Watermarking TechniquesIn image watermarking technique different type of technique is used as Digital Image ndash artificial resemblance of original object stored in form of binary numbers Image Watermarking ndash putting in some information that ensures your authentication of the document in the image itself Spatial domain algorithms- Two robust spatial-domain watermarking algorithms for image copyright protection are described as

The first one is robust against compression filtering and cropping Like all published crop-proof algorithms the one proposed here requires the original image for mark recovery Robustness against compression and filtering is obtained by using the JPEG algorithm to decide on mark location and magnitude robustness against cropping is achieved through a repetition code

The second watermarking algorithm uses visual components and is robust against compression filtering scaling and moderate rotations

The Discrete Cosine Transform (DCT)The discrete cosine transform (DCT) helps separate the image into parts (or spectral sub-bands) of differing importance (with respect to the images visual quality) The DCT is similar to the discrete Fourier transform it transforms a signal or image from the spatial domain to the frequency domain

Page | 16

Fig 10 DCT process diagramThe discrete cosine transform (DCT) is a technique for converting a signal into elementary frequency components It is widely used in image compression

Image Histogram

An image histogram is a type of histogram which acts as a graphical representation of the tonal distribution in a digital image It plots the number of pixels for each tonal value By looking at the histogram for a specific image a viewer will be able to judge the entire tonal distribution at a glance63 Audio Watermarking TechniquesIn audio watermarking technique different type of technique is used as

LSB watermarking - Least Significant Bit algorithm that embedding watermark into the least important part of the primary image and the watermark can be extracted from the primary image

The idea behind this watermarking technique is the following if you see you image as a matrix NxM (where N and M are the dimension of the image) you can represent the value of the pixel in the position (ij) as a binary number this binary can be then divided in all of its bit so that you will have a most significant bit (the one that contains quite a lot of information and a least significant bit that contains few information)

Quantisation watermarking - A new method for watermarking based on vector quantisation is proposed It is efficient for implementation with conventional techniques and simulation results show its robustness under a variety of attacks It also represents superiority over existing algorithms

Wavelet transform domain algorithms - The wavelet transform-domain least-mean square (WTDLMS) algorithm is known to have in general a faster convergence rate than the time-domain LMS algorithm and can find many applications in signal processing and communications areas However the computational complexity of the wavelet filter bank is relatively high In this work we show how to exploit the redundancy which exists in the computation of the wavelet coefficients between successive iterations so as to significantly reduce the computational load of the algorithm

Page | 17

7 Applications of Digital Watermarking

There is a wide variety of applications for watermarking The requirements of watermarking systems are always based on the application as for obvious reasons there is no ldquouniversalrdquo watermarking method Although it has to be robust in general different level of required robustness can be identified besides the specific characteristics of the problem which make the watermarking a suitable solution Several applications are listed below

Owner identification ndash similar to copyright protection to establish ownership of the content

Copy protection ndash also known as copy control to prevent people from making illegal copies of copyrighted content

Content authentication ndash to detect modifications of the content as a sign of invalid authentication

Fingerprinting ndash sometimes referred as transaction tracking or traitor tracking to trace back illegal duplication and distribution of the content

Broadcast monitoring ndash specifically for advertisements and in entertainment industries to monitor content being broadcasted as contracted and by the authorized source

Medical applications ndash known as invertible watermarking to provide both authentication and confidentiality in a reversible manner without affecting the medical image in any way

Page | 18

8 Limitations of digital watermarking

In January 1997 a counterfeiting scheme has been demonstrated for a class of invertible feature-based frequency domain invisible watermarking algorithms This counterfeiting scheme could be used to subvert ownership claims because the recovery of the digital signature from a watermarked image requires a comparison with an original The counterfeiting scheme works by first creating a counterfeit watermarked copy from the genuine watermarked copy by effectively inverting the genuine watermark This inversion creates a counterfeit of the original image A comparison of the decoded versions of both yield the owners (authorized) and the forged (inverted) signature This the technique of establishing legitimate ownership recovering the signature watermark by comparing a watermarked image with the original image breaks down It can be shown that both the legitimate signature and counterfeiters signature inhere in both the watermarked and counterfeit watermarked copies Thus while it may be demonstrated that at least one recipient has a counterfeit watermarked copy it cannot be determined which it is

Page | 19

9 Proposed Work

In traditional symmetric watermarking schemes the key used for watermark embedding must be available at the watermark detector This leads to a security problem if the detectors are implemented in consumer devices that are spread all over the world So asymmetric watermarking schemes also named public key digital watermarking schemes attract more and more attentions In such a public key watermarking system the private key is used for watermarking embedding and the public key is used only for watermarking detection The private key is kept for secret and the watermarks cannot easily be removed with public key

We are actually concentrating on studying public key watermarking techniques to evaluate and compare their performance in comparison to private key water marking techniques

Page | 20

10 RESEARCH DIRECTIONS

101 Study on Watermarking Algorithm

Digital watermarking technology processing contains two cores watermark embedding algorithm and detection algorithm Robustness imperceptibility invisibility and security of digital watermarking is generally the focus of the requirements

102 Study on Watermarking Theory

Although there are many published articles on watermarking the current watermarking technology canrsquot yet fill the actual requirements of most users The lack of standards interoperability problems as well as a suit of accurate and realistic requirements to watermarking system is still hinder the development of digital watermarking technology

There are still many problems to be resolved In order to be more widely used digital watermarking should establish a series of standards or agreements such as the standards of watermark embedding detection and certification Different watermarking algorithm has different compatibility and that is obviously not conducive to promoting the application of digital watermarking

103 Study on Watermark Attack

The relationship between watermark attack and watermarking algorithm is the same as spear and shield they restrict each other and promote each other as well To develop the technologies combined with cryptography authentication and digital signature is probably the direction of resistance development to various attacks

Page | 21

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

57 Visible watermark

Visible watermarks are especially useful for conveying an immediate claim of ownership The main advantage is that they virtually eliminate the commercial value of the document to a would-be thief without lessening the documents utility for legitimate authorized purposes A familiar example is in the video domain where a logo is placed in a corner of the screen image

58 Invisible-Robust watermark

The invisible-robust watermark is embedded in such a way that alternations madeto the pixel value are perceptually not noticed and it can be recovered only with appropriate decoding mechanism

59 Invisible-Fragile watermarkThe invisible-fragile watermark is embedded in such a way that any manipulation or modification of the image would alter or destroy the watermark

510 Dual watermark

Dual watermark is a combination of a visible and an invisible watermark In this type of water mark an invisible watermark is used as a backup for the visible watermark as clear from the following diagram

Figure Schematic representation of dual watermarking

From application point of view digital watermark could be as below

511 source based

Source-based watermark are desirable for ownership identification or authentication where a unique watermark identifying the owner is introduced to all the copies of a particular image being distributed A source-based watermark could be used for authentication and to determine whether a received image or other electronic data has been tampered with

Page | 13

512 destination based

The watermark could also be destination based where each distributed copy gets a unique watermark identifying the particular buyer The destination based watermark could be used to trace the buyer in the case of illegal reselling

6 Digital Watermarking Techniques

61 Text-based Watermarking

62 Image Watermarking

63 Audio Watermarking

64 Video Watermarking

61Text-Based Watermarking Techniques

A The text watermarking based on the fine-tuning of document structure

This is a technique which makes the text as a binary image it obtains watermark through fine-tuning the display style and it is imperceptibly by human visual The most classic algorithm is proposed by Brassil and Maxemchuk it gives many different ways to insert watermark in the PostScript document as follows

a) Line-shift encoding for the line space of a text file is uniform the coding method embeds a watermark by vertical shifting an entire line when the movement away from no more than 1 300 inches the human eye cannot easily perceive by analyzing the line spacing can determine whether it contains text watermark the process does not require the participation of the original text

b) word-shift encoding this coding method embeds watermark by level shifting some special words in a line When a word is shifted to right or left itrsquos adjacent words are not moving not moving words are as references location for the process of decoding Experience found that the human eye cannot identify the 1 150 inches below the level of displacement As the document is not a fixed word spacing so to determine whether it contains watermark needs the text of the original documents

c) Characteristics coding the coding method inserts a marker by changing the particular characteristics of a letter such as changing the height of a individual letter fonts etc The above-mentioned three kinds of coding methods are to use the spatial characteristics of text to embed the watermark These algorithm entirely depend on the text format (line-shift word-shift characteristics coding etc) there are many shortcomings such as not enough antiaggressive less robust not well hidden

Page | 14

Fig 9 Text water markingB The text watermark based on the not important content For a text when some of the expressions of the text occur Some minor changes there is no impact for understanding the document for this point the text watermark can be embedded Typical methods include inserting punctuation in sentences or inserting space at the end of a line For example we can store binary information by setting or not setting the comma in the two side-by-side words with and or or to connect

Specifically if the guns butter and flowers expresses the logic 1 then the guns butter and flower is logic0Weakness of such method that is the watermark information may be missing in the transmission process of application In addition the source text can not be arbitrary This method is not currently the main method of text watermarking

C The text watermark based on ldquoreplace the content of textrdquo The method is derived from information hiding technology It looks source text as the significance sequence instead of text images embedded in the course of the text is converted to vector with the same or similar meaning of the text of the secret process So watermark can be embedded by converting the source text into the same or similar meaning of hidden text

Usually in the English text many words have synonyms such as big and 1arge smart and clever and so on so we can elect these specific words of the text constitute a synonym replacement tables The word needs to be replaced said logic 0 the words that do not need to replace the logic 1So the secret data can be hidden in the text the number of hidden data relates to the synonym appear frequency in the text the method also applies to Chinese text The method of synonym replacement hide information by modifying the contents of the text it not only has better robustness but also do not need to rely on a specific document format However this approach requires source text cannot be arbitrary that is should contain a certain number of synonyms have been defined and in the process of extracting information needs the synonyms replace table

D The text watermark Based on natural language processing technology

Natural language processing is to in some specific applications automatically handling the text written in natural language such as machine translation information retrieval information

Page | 15

extraction data mining and intelligent search engines and so on after many years of development of the Natural language processing technology much experience and techniques have been accumulated such as word segmentation syntax analysis restatement eliminate the ambiguity of words and so on These are the foundation of The text watermark Based on natural language processing technology and compared to previous methods through the use of natural language processing technology embedded watermark informationmore secure reliable

Challenges

Marking copies uniquely

Making necessary for a recipient to provide personal information

Using encryption

Uses

Protect electronic documents

Paper documents are easy to copy and distribute electronically

62 Image Watermarking TechniquesIn image watermarking technique different type of technique is used as Digital Image ndash artificial resemblance of original object stored in form of binary numbers Image Watermarking ndash putting in some information that ensures your authentication of the document in the image itself Spatial domain algorithms- Two robust spatial-domain watermarking algorithms for image copyright protection are described as

The first one is robust against compression filtering and cropping Like all published crop-proof algorithms the one proposed here requires the original image for mark recovery Robustness against compression and filtering is obtained by using the JPEG algorithm to decide on mark location and magnitude robustness against cropping is achieved through a repetition code

The second watermarking algorithm uses visual components and is robust against compression filtering scaling and moderate rotations

The Discrete Cosine Transform (DCT)The discrete cosine transform (DCT) helps separate the image into parts (or spectral sub-bands) of differing importance (with respect to the images visual quality) The DCT is similar to the discrete Fourier transform it transforms a signal or image from the spatial domain to the frequency domain

Page | 16

Fig 10 DCT process diagramThe discrete cosine transform (DCT) is a technique for converting a signal into elementary frequency components It is widely used in image compression

Image Histogram

An image histogram is a type of histogram which acts as a graphical representation of the tonal distribution in a digital image It plots the number of pixels for each tonal value By looking at the histogram for a specific image a viewer will be able to judge the entire tonal distribution at a glance63 Audio Watermarking TechniquesIn audio watermarking technique different type of technique is used as

LSB watermarking - Least Significant Bit algorithm that embedding watermark into the least important part of the primary image and the watermark can be extracted from the primary image

The idea behind this watermarking technique is the following if you see you image as a matrix NxM (where N and M are the dimension of the image) you can represent the value of the pixel in the position (ij) as a binary number this binary can be then divided in all of its bit so that you will have a most significant bit (the one that contains quite a lot of information and a least significant bit that contains few information)

Quantisation watermarking - A new method for watermarking based on vector quantisation is proposed It is efficient for implementation with conventional techniques and simulation results show its robustness under a variety of attacks It also represents superiority over existing algorithms

Wavelet transform domain algorithms - The wavelet transform-domain least-mean square (WTDLMS) algorithm is known to have in general a faster convergence rate than the time-domain LMS algorithm and can find many applications in signal processing and communications areas However the computational complexity of the wavelet filter bank is relatively high In this work we show how to exploit the redundancy which exists in the computation of the wavelet coefficients between successive iterations so as to significantly reduce the computational load of the algorithm

Page | 17

7 Applications of Digital Watermarking

There is a wide variety of applications for watermarking The requirements of watermarking systems are always based on the application as for obvious reasons there is no ldquouniversalrdquo watermarking method Although it has to be robust in general different level of required robustness can be identified besides the specific characteristics of the problem which make the watermarking a suitable solution Several applications are listed below

Owner identification ndash similar to copyright protection to establish ownership of the content

Copy protection ndash also known as copy control to prevent people from making illegal copies of copyrighted content

Content authentication ndash to detect modifications of the content as a sign of invalid authentication

Fingerprinting ndash sometimes referred as transaction tracking or traitor tracking to trace back illegal duplication and distribution of the content

Broadcast monitoring ndash specifically for advertisements and in entertainment industries to monitor content being broadcasted as contracted and by the authorized source

Medical applications ndash known as invertible watermarking to provide both authentication and confidentiality in a reversible manner without affecting the medical image in any way

Page | 18

8 Limitations of digital watermarking

In January 1997 a counterfeiting scheme has been demonstrated for a class of invertible feature-based frequency domain invisible watermarking algorithms This counterfeiting scheme could be used to subvert ownership claims because the recovery of the digital signature from a watermarked image requires a comparison with an original The counterfeiting scheme works by first creating a counterfeit watermarked copy from the genuine watermarked copy by effectively inverting the genuine watermark This inversion creates a counterfeit of the original image A comparison of the decoded versions of both yield the owners (authorized) and the forged (inverted) signature This the technique of establishing legitimate ownership recovering the signature watermark by comparing a watermarked image with the original image breaks down It can be shown that both the legitimate signature and counterfeiters signature inhere in both the watermarked and counterfeit watermarked copies Thus while it may be demonstrated that at least one recipient has a counterfeit watermarked copy it cannot be determined which it is

Page | 19

9 Proposed Work

In traditional symmetric watermarking schemes the key used for watermark embedding must be available at the watermark detector This leads to a security problem if the detectors are implemented in consumer devices that are spread all over the world So asymmetric watermarking schemes also named public key digital watermarking schemes attract more and more attentions In such a public key watermarking system the private key is used for watermarking embedding and the public key is used only for watermarking detection The private key is kept for secret and the watermarks cannot easily be removed with public key

We are actually concentrating on studying public key watermarking techniques to evaluate and compare their performance in comparison to private key water marking techniques

Page | 20

10 RESEARCH DIRECTIONS

101 Study on Watermarking Algorithm

Digital watermarking technology processing contains two cores watermark embedding algorithm and detection algorithm Robustness imperceptibility invisibility and security of digital watermarking is generally the focus of the requirements

102 Study on Watermarking Theory

Although there are many published articles on watermarking the current watermarking technology canrsquot yet fill the actual requirements of most users The lack of standards interoperability problems as well as a suit of accurate and realistic requirements to watermarking system is still hinder the development of digital watermarking technology

There are still many problems to be resolved In order to be more widely used digital watermarking should establish a series of standards or agreements such as the standards of watermark embedding detection and certification Different watermarking algorithm has different compatibility and that is obviously not conducive to promoting the application of digital watermarking

103 Study on Watermark Attack

The relationship between watermark attack and watermarking algorithm is the same as spear and shield they restrict each other and promote each other as well To develop the technologies combined with cryptography authentication and digital signature is probably the direction of resistance development to various attacks

Page | 21

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

512 destination based

The watermark could also be destination based where each distributed copy gets a unique watermark identifying the particular buyer The destination based watermark could be used to trace the buyer in the case of illegal reselling

6 Digital Watermarking Techniques

61 Text-based Watermarking

62 Image Watermarking

63 Audio Watermarking

64 Video Watermarking

61Text-Based Watermarking Techniques

A The text watermarking based on the fine-tuning of document structure

This is a technique which makes the text as a binary image it obtains watermark through fine-tuning the display style and it is imperceptibly by human visual The most classic algorithm is proposed by Brassil and Maxemchuk it gives many different ways to insert watermark in the PostScript document as follows

a) Line-shift encoding for the line space of a text file is uniform the coding method embeds a watermark by vertical shifting an entire line when the movement away from no more than 1 300 inches the human eye cannot easily perceive by analyzing the line spacing can determine whether it contains text watermark the process does not require the participation of the original text

b) word-shift encoding this coding method embeds watermark by level shifting some special words in a line When a word is shifted to right or left itrsquos adjacent words are not moving not moving words are as references location for the process of decoding Experience found that the human eye cannot identify the 1 150 inches below the level of displacement As the document is not a fixed word spacing so to determine whether it contains watermark needs the text of the original documents

c) Characteristics coding the coding method inserts a marker by changing the particular characteristics of a letter such as changing the height of a individual letter fonts etc The above-mentioned three kinds of coding methods are to use the spatial characteristics of text to embed the watermark These algorithm entirely depend on the text format (line-shift word-shift characteristics coding etc) there are many shortcomings such as not enough antiaggressive less robust not well hidden

Page | 14

Fig 9 Text water markingB The text watermark based on the not important content For a text when some of the expressions of the text occur Some minor changes there is no impact for understanding the document for this point the text watermark can be embedded Typical methods include inserting punctuation in sentences or inserting space at the end of a line For example we can store binary information by setting or not setting the comma in the two side-by-side words with and or or to connect

Specifically if the guns butter and flowers expresses the logic 1 then the guns butter and flower is logic0Weakness of such method that is the watermark information may be missing in the transmission process of application In addition the source text can not be arbitrary This method is not currently the main method of text watermarking

C The text watermark based on ldquoreplace the content of textrdquo The method is derived from information hiding technology It looks source text as the significance sequence instead of text images embedded in the course of the text is converted to vector with the same or similar meaning of the text of the secret process So watermark can be embedded by converting the source text into the same or similar meaning of hidden text

Usually in the English text many words have synonyms such as big and 1arge smart and clever and so on so we can elect these specific words of the text constitute a synonym replacement tables The word needs to be replaced said logic 0 the words that do not need to replace the logic 1So the secret data can be hidden in the text the number of hidden data relates to the synonym appear frequency in the text the method also applies to Chinese text The method of synonym replacement hide information by modifying the contents of the text it not only has better robustness but also do not need to rely on a specific document format However this approach requires source text cannot be arbitrary that is should contain a certain number of synonyms have been defined and in the process of extracting information needs the synonyms replace table

D The text watermark Based on natural language processing technology

Natural language processing is to in some specific applications automatically handling the text written in natural language such as machine translation information retrieval information

Page | 15

extraction data mining and intelligent search engines and so on after many years of development of the Natural language processing technology much experience and techniques have been accumulated such as word segmentation syntax analysis restatement eliminate the ambiguity of words and so on These are the foundation of The text watermark Based on natural language processing technology and compared to previous methods through the use of natural language processing technology embedded watermark informationmore secure reliable

Challenges

Marking copies uniquely

Making necessary for a recipient to provide personal information

Using encryption

Uses

Protect electronic documents

Paper documents are easy to copy and distribute electronically

62 Image Watermarking TechniquesIn image watermarking technique different type of technique is used as Digital Image ndash artificial resemblance of original object stored in form of binary numbers Image Watermarking ndash putting in some information that ensures your authentication of the document in the image itself Spatial domain algorithms- Two robust spatial-domain watermarking algorithms for image copyright protection are described as

The first one is robust against compression filtering and cropping Like all published crop-proof algorithms the one proposed here requires the original image for mark recovery Robustness against compression and filtering is obtained by using the JPEG algorithm to decide on mark location and magnitude robustness against cropping is achieved through a repetition code

The second watermarking algorithm uses visual components and is robust against compression filtering scaling and moderate rotations

The Discrete Cosine Transform (DCT)The discrete cosine transform (DCT) helps separate the image into parts (or spectral sub-bands) of differing importance (with respect to the images visual quality) The DCT is similar to the discrete Fourier transform it transforms a signal or image from the spatial domain to the frequency domain

Page | 16

Fig 10 DCT process diagramThe discrete cosine transform (DCT) is a technique for converting a signal into elementary frequency components It is widely used in image compression

Image Histogram

An image histogram is a type of histogram which acts as a graphical representation of the tonal distribution in a digital image It plots the number of pixels for each tonal value By looking at the histogram for a specific image a viewer will be able to judge the entire tonal distribution at a glance63 Audio Watermarking TechniquesIn audio watermarking technique different type of technique is used as

LSB watermarking - Least Significant Bit algorithm that embedding watermark into the least important part of the primary image and the watermark can be extracted from the primary image

The idea behind this watermarking technique is the following if you see you image as a matrix NxM (where N and M are the dimension of the image) you can represent the value of the pixel in the position (ij) as a binary number this binary can be then divided in all of its bit so that you will have a most significant bit (the one that contains quite a lot of information and a least significant bit that contains few information)

Quantisation watermarking - A new method for watermarking based on vector quantisation is proposed It is efficient for implementation with conventional techniques and simulation results show its robustness under a variety of attacks It also represents superiority over existing algorithms

Wavelet transform domain algorithms - The wavelet transform-domain least-mean square (WTDLMS) algorithm is known to have in general a faster convergence rate than the time-domain LMS algorithm and can find many applications in signal processing and communications areas However the computational complexity of the wavelet filter bank is relatively high In this work we show how to exploit the redundancy which exists in the computation of the wavelet coefficients between successive iterations so as to significantly reduce the computational load of the algorithm

Page | 17

7 Applications of Digital Watermarking

There is a wide variety of applications for watermarking The requirements of watermarking systems are always based on the application as for obvious reasons there is no ldquouniversalrdquo watermarking method Although it has to be robust in general different level of required robustness can be identified besides the specific characteristics of the problem which make the watermarking a suitable solution Several applications are listed below

Owner identification ndash similar to copyright protection to establish ownership of the content

Copy protection ndash also known as copy control to prevent people from making illegal copies of copyrighted content

Content authentication ndash to detect modifications of the content as a sign of invalid authentication

Fingerprinting ndash sometimes referred as transaction tracking or traitor tracking to trace back illegal duplication and distribution of the content

Broadcast monitoring ndash specifically for advertisements and in entertainment industries to monitor content being broadcasted as contracted and by the authorized source

Medical applications ndash known as invertible watermarking to provide both authentication and confidentiality in a reversible manner without affecting the medical image in any way

Page | 18

8 Limitations of digital watermarking

In January 1997 a counterfeiting scheme has been demonstrated for a class of invertible feature-based frequency domain invisible watermarking algorithms This counterfeiting scheme could be used to subvert ownership claims because the recovery of the digital signature from a watermarked image requires a comparison with an original The counterfeiting scheme works by first creating a counterfeit watermarked copy from the genuine watermarked copy by effectively inverting the genuine watermark This inversion creates a counterfeit of the original image A comparison of the decoded versions of both yield the owners (authorized) and the forged (inverted) signature This the technique of establishing legitimate ownership recovering the signature watermark by comparing a watermarked image with the original image breaks down It can be shown that both the legitimate signature and counterfeiters signature inhere in both the watermarked and counterfeit watermarked copies Thus while it may be demonstrated that at least one recipient has a counterfeit watermarked copy it cannot be determined which it is

Page | 19

9 Proposed Work

In traditional symmetric watermarking schemes the key used for watermark embedding must be available at the watermark detector This leads to a security problem if the detectors are implemented in consumer devices that are spread all over the world So asymmetric watermarking schemes also named public key digital watermarking schemes attract more and more attentions In such a public key watermarking system the private key is used for watermarking embedding and the public key is used only for watermarking detection The private key is kept for secret and the watermarks cannot easily be removed with public key

We are actually concentrating on studying public key watermarking techniques to evaluate and compare their performance in comparison to private key water marking techniques

Page | 20

10 RESEARCH DIRECTIONS

101 Study on Watermarking Algorithm

Digital watermarking technology processing contains two cores watermark embedding algorithm and detection algorithm Robustness imperceptibility invisibility and security of digital watermarking is generally the focus of the requirements

102 Study on Watermarking Theory

Although there are many published articles on watermarking the current watermarking technology canrsquot yet fill the actual requirements of most users The lack of standards interoperability problems as well as a suit of accurate and realistic requirements to watermarking system is still hinder the development of digital watermarking technology

There are still many problems to be resolved In order to be more widely used digital watermarking should establish a series of standards or agreements such as the standards of watermark embedding detection and certification Different watermarking algorithm has different compatibility and that is obviously not conducive to promoting the application of digital watermarking

103 Study on Watermark Attack

The relationship between watermark attack and watermarking algorithm is the same as spear and shield they restrict each other and promote each other as well To develop the technologies combined with cryptography authentication and digital signature is probably the direction of resistance development to various attacks

Page | 21

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

Fig 9 Text water markingB The text watermark based on the not important content For a text when some of the expressions of the text occur Some minor changes there is no impact for understanding the document for this point the text watermark can be embedded Typical methods include inserting punctuation in sentences or inserting space at the end of a line For example we can store binary information by setting or not setting the comma in the two side-by-side words with and or or to connect

Specifically if the guns butter and flowers expresses the logic 1 then the guns butter and flower is logic0Weakness of such method that is the watermark information may be missing in the transmission process of application In addition the source text can not be arbitrary This method is not currently the main method of text watermarking

C The text watermark based on ldquoreplace the content of textrdquo The method is derived from information hiding technology It looks source text as the significance sequence instead of text images embedded in the course of the text is converted to vector with the same or similar meaning of the text of the secret process So watermark can be embedded by converting the source text into the same or similar meaning of hidden text

Usually in the English text many words have synonyms such as big and 1arge smart and clever and so on so we can elect these specific words of the text constitute a synonym replacement tables The word needs to be replaced said logic 0 the words that do not need to replace the logic 1So the secret data can be hidden in the text the number of hidden data relates to the synonym appear frequency in the text the method also applies to Chinese text The method of synonym replacement hide information by modifying the contents of the text it not only has better robustness but also do not need to rely on a specific document format However this approach requires source text cannot be arbitrary that is should contain a certain number of synonyms have been defined and in the process of extracting information needs the synonyms replace table

D The text watermark Based on natural language processing technology

Natural language processing is to in some specific applications automatically handling the text written in natural language such as machine translation information retrieval information

Page | 15

extraction data mining and intelligent search engines and so on after many years of development of the Natural language processing technology much experience and techniques have been accumulated such as word segmentation syntax analysis restatement eliminate the ambiguity of words and so on These are the foundation of The text watermark Based on natural language processing technology and compared to previous methods through the use of natural language processing technology embedded watermark informationmore secure reliable

Challenges

Marking copies uniquely

Making necessary for a recipient to provide personal information

Using encryption

Uses

Protect electronic documents

Paper documents are easy to copy and distribute electronically

62 Image Watermarking TechniquesIn image watermarking technique different type of technique is used as Digital Image ndash artificial resemblance of original object stored in form of binary numbers Image Watermarking ndash putting in some information that ensures your authentication of the document in the image itself Spatial domain algorithms- Two robust spatial-domain watermarking algorithms for image copyright protection are described as

The first one is robust against compression filtering and cropping Like all published crop-proof algorithms the one proposed here requires the original image for mark recovery Robustness against compression and filtering is obtained by using the JPEG algorithm to decide on mark location and magnitude robustness against cropping is achieved through a repetition code

The second watermarking algorithm uses visual components and is robust against compression filtering scaling and moderate rotations

The Discrete Cosine Transform (DCT)The discrete cosine transform (DCT) helps separate the image into parts (or spectral sub-bands) of differing importance (with respect to the images visual quality) The DCT is similar to the discrete Fourier transform it transforms a signal or image from the spatial domain to the frequency domain

Page | 16

Fig 10 DCT process diagramThe discrete cosine transform (DCT) is a technique for converting a signal into elementary frequency components It is widely used in image compression

Image Histogram

An image histogram is a type of histogram which acts as a graphical representation of the tonal distribution in a digital image It plots the number of pixels for each tonal value By looking at the histogram for a specific image a viewer will be able to judge the entire tonal distribution at a glance63 Audio Watermarking TechniquesIn audio watermarking technique different type of technique is used as

LSB watermarking - Least Significant Bit algorithm that embedding watermark into the least important part of the primary image and the watermark can be extracted from the primary image

The idea behind this watermarking technique is the following if you see you image as a matrix NxM (where N and M are the dimension of the image) you can represent the value of the pixel in the position (ij) as a binary number this binary can be then divided in all of its bit so that you will have a most significant bit (the one that contains quite a lot of information and a least significant bit that contains few information)

Quantisation watermarking - A new method for watermarking based on vector quantisation is proposed It is efficient for implementation with conventional techniques and simulation results show its robustness under a variety of attacks It also represents superiority over existing algorithms

Wavelet transform domain algorithms - The wavelet transform-domain least-mean square (WTDLMS) algorithm is known to have in general a faster convergence rate than the time-domain LMS algorithm and can find many applications in signal processing and communications areas However the computational complexity of the wavelet filter bank is relatively high In this work we show how to exploit the redundancy which exists in the computation of the wavelet coefficients between successive iterations so as to significantly reduce the computational load of the algorithm

Page | 17

7 Applications of Digital Watermarking

There is a wide variety of applications for watermarking The requirements of watermarking systems are always based on the application as for obvious reasons there is no ldquouniversalrdquo watermarking method Although it has to be robust in general different level of required robustness can be identified besides the specific characteristics of the problem which make the watermarking a suitable solution Several applications are listed below

Owner identification ndash similar to copyright protection to establish ownership of the content

Copy protection ndash also known as copy control to prevent people from making illegal copies of copyrighted content

Content authentication ndash to detect modifications of the content as a sign of invalid authentication

Fingerprinting ndash sometimes referred as transaction tracking or traitor tracking to trace back illegal duplication and distribution of the content

Broadcast monitoring ndash specifically for advertisements and in entertainment industries to monitor content being broadcasted as contracted and by the authorized source

Medical applications ndash known as invertible watermarking to provide both authentication and confidentiality in a reversible manner without affecting the medical image in any way

Page | 18

8 Limitations of digital watermarking

In January 1997 a counterfeiting scheme has been demonstrated for a class of invertible feature-based frequency domain invisible watermarking algorithms This counterfeiting scheme could be used to subvert ownership claims because the recovery of the digital signature from a watermarked image requires a comparison with an original The counterfeiting scheme works by first creating a counterfeit watermarked copy from the genuine watermarked copy by effectively inverting the genuine watermark This inversion creates a counterfeit of the original image A comparison of the decoded versions of both yield the owners (authorized) and the forged (inverted) signature This the technique of establishing legitimate ownership recovering the signature watermark by comparing a watermarked image with the original image breaks down It can be shown that both the legitimate signature and counterfeiters signature inhere in both the watermarked and counterfeit watermarked copies Thus while it may be demonstrated that at least one recipient has a counterfeit watermarked copy it cannot be determined which it is

Page | 19

9 Proposed Work

In traditional symmetric watermarking schemes the key used for watermark embedding must be available at the watermark detector This leads to a security problem if the detectors are implemented in consumer devices that are spread all over the world So asymmetric watermarking schemes also named public key digital watermarking schemes attract more and more attentions In such a public key watermarking system the private key is used for watermarking embedding and the public key is used only for watermarking detection The private key is kept for secret and the watermarks cannot easily be removed with public key

We are actually concentrating on studying public key watermarking techniques to evaluate and compare their performance in comparison to private key water marking techniques

Page | 20

10 RESEARCH DIRECTIONS

101 Study on Watermarking Algorithm

Digital watermarking technology processing contains two cores watermark embedding algorithm and detection algorithm Robustness imperceptibility invisibility and security of digital watermarking is generally the focus of the requirements

102 Study on Watermarking Theory

Although there are many published articles on watermarking the current watermarking technology canrsquot yet fill the actual requirements of most users The lack of standards interoperability problems as well as a suit of accurate and realistic requirements to watermarking system is still hinder the development of digital watermarking technology

There are still many problems to be resolved In order to be more widely used digital watermarking should establish a series of standards or agreements such as the standards of watermark embedding detection and certification Different watermarking algorithm has different compatibility and that is obviously not conducive to promoting the application of digital watermarking

103 Study on Watermark Attack

The relationship between watermark attack and watermarking algorithm is the same as spear and shield they restrict each other and promote each other as well To develop the technologies combined with cryptography authentication and digital signature is probably the direction of resistance development to various attacks

Page | 21

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

extraction data mining and intelligent search engines and so on after many years of development of the Natural language processing technology much experience and techniques have been accumulated such as word segmentation syntax analysis restatement eliminate the ambiguity of words and so on These are the foundation of The text watermark Based on natural language processing technology and compared to previous methods through the use of natural language processing technology embedded watermark informationmore secure reliable

Challenges

Marking copies uniquely

Making necessary for a recipient to provide personal information

Using encryption

Uses

Protect electronic documents

Paper documents are easy to copy and distribute electronically

62 Image Watermarking TechniquesIn image watermarking technique different type of technique is used as Digital Image ndash artificial resemblance of original object stored in form of binary numbers Image Watermarking ndash putting in some information that ensures your authentication of the document in the image itself Spatial domain algorithms- Two robust spatial-domain watermarking algorithms for image copyright protection are described as

The first one is robust against compression filtering and cropping Like all published crop-proof algorithms the one proposed here requires the original image for mark recovery Robustness against compression and filtering is obtained by using the JPEG algorithm to decide on mark location and magnitude robustness against cropping is achieved through a repetition code

The second watermarking algorithm uses visual components and is robust against compression filtering scaling and moderate rotations

The Discrete Cosine Transform (DCT)The discrete cosine transform (DCT) helps separate the image into parts (or spectral sub-bands) of differing importance (with respect to the images visual quality) The DCT is similar to the discrete Fourier transform it transforms a signal or image from the spatial domain to the frequency domain

Page | 16

Fig 10 DCT process diagramThe discrete cosine transform (DCT) is a technique for converting a signal into elementary frequency components It is widely used in image compression

Image Histogram

An image histogram is a type of histogram which acts as a graphical representation of the tonal distribution in a digital image It plots the number of pixels for each tonal value By looking at the histogram for a specific image a viewer will be able to judge the entire tonal distribution at a glance63 Audio Watermarking TechniquesIn audio watermarking technique different type of technique is used as

LSB watermarking - Least Significant Bit algorithm that embedding watermark into the least important part of the primary image and the watermark can be extracted from the primary image

The idea behind this watermarking technique is the following if you see you image as a matrix NxM (where N and M are the dimension of the image) you can represent the value of the pixel in the position (ij) as a binary number this binary can be then divided in all of its bit so that you will have a most significant bit (the one that contains quite a lot of information and a least significant bit that contains few information)

Quantisation watermarking - A new method for watermarking based on vector quantisation is proposed It is efficient for implementation with conventional techniques and simulation results show its robustness under a variety of attacks It also represents superiority over existing algorithms

Wavelet transform domain algorithms - The wavelet transform-domain least-mean square (WTDLMS) algorithm is known to have in general a faster convergence rate than the time-domain LMS algorithm and can find many applications in signal processing and communications areas However the computational complexity of the wavelet filter bank is relatively high In this work we show how to exploit the redundancy which exists in the computation of the wavelet coefficients between successive iterations so as to significantly reduce the computational load of the algorithm

Page | 17

7 Applications of Digital Watermarking

There is a wide variety of applications for watermarking The requirements of watermarking systems are always based on the application as for obvious reasons there is no ldquouniversalrdquo watermarking method Although it has to be robust in general different level of required robustness can be identified besides the specific characteristics of the problem which make the watermarking a suitable solution Several applications are listed below

Owner identification ndash similar to copyright protection to establish ownership of the content

Copy protection ndash also known as copy control to prevent people from making illegal copies of copyrighted content

Content authentication ndash to detect modifications of the content as a sign of invalid authentication

Fingerprinting ndash sometimes referred as transaction tracking or traitor tracking to trace back illegal duplication and distribution of the content

Broadcast monitoring ndash specifically for advertisements and in entertainment industries to monitor content being broadcasted as contracted and by the authorized source

Medical applications ndash known as invertible watermarking to provide both authentication and confidentiality in a reversible manner without affecting the medical image in any way

Page | 18

8 Limitations of digital watermarking

In January 1997 a counterfeiting scheme has been demonstrated for a class of invertible feature-based frequency domain invisible watermarking algorithms This counterfeiting scheme could be used to subvert ownership claims because the recovery of the digital signature from a watermarked image requires a comparison with an original The counterfeiting scheme works by first creating a counterfeit watermarked copy from the genuine watermarked copy by effectively inverting the genuine watermark This inversion creates a counterfeit of the original image A comparison of the decoded versions of both yield the owners (authorized) and the forged (inverted) signature This the technique of establishing legitimate ownership recovering the signature watermark by comparing a watermarked image with the original image breaks down It can be shown that both the legitimate signature and counterfeiters signature inhere in both the watermarked and counterfeit watermarked copies Thus while it may be demonstrated that at least one recipient has a counterfeit watermarked copy it cannot be determined which it is

Page | 19

9 Proposed Work

In traditional symmetric watermarking schemes the key used for watermark embedding must be available at the watermark detector This leads to a security problem if the detectors are implemented in consumer devices that are spread all over the world So asymmetric watermarking schemes also named public key digital watermarking schemes attract more and more attentions In such a public key watermarking system the private key is used for watermarking embedding and the public key is used only for watermarking detection The private key is kept for secret and the watermarks cannot easily be removed with public key

We are actually concentrating on studying public key watermarking techniques to evaluate and compare their performance in comparison to private key water marking techniques

Page | 20

10 RESEARCH DIRECTIONS

101 Study on Watermarking Algorithm

Digital watermarking technology processing contains two cores watermark embedding algorithm and detection algorithm Robustness imperceptibility invisibility and security of digital watermarking is generally the focus of the requirements

102 Study on Watermarking Theory

Although there are many published articles on watermarking the current watermarking technology canrsquot yet fill the actual requirements of most users The lack of standards interoperability problems as well as a suit of accurate and realistic requirements to watermarking system is still hinder the development of digital watermarking technology

There are still many problems to be resolved In order to be more widely used digital watermarking should establish a series of standards or agreements such as the standards of watermark embedding detection and certification Different watermarking algorithm has different compatibility and that is obviously not conducive to promoting the application of digital watermarking

103 Study on Watermark Attack

The relationship between watermark attack and watermarking algorithm is the same as spear and shield they restrict each other and promote each other as well To develop the technologies combined with cryptography authentication and digital signature is probably the direction of resistance development to various attacks

Page | 21

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

Fig 10 DCT process diagramThe discrete cosine transform (DCT) is a technique for converting a signal into elementary frequency components It is widely used in image compression

Image Histogram

An image histogram is a type of histogram which acts as a graphical representation of the tonal distribution in a digital image It plots the number of pixels for each tonal value By looking at the histogram for a specific image a viewer will be able to judge the entire tonal distribution at a glance63 Audio Watermarking TechniquesIn audio watermarking technique different type of technique is used as

LSB watermarking - Least Significant Bit algorithm that embedding watermark into the least important part of the primary image and the watermark can be extracted from the primary image

The idea behind this watermarking technique is the following if you see you image as a matrix NxM (where N and M are the dimension of the image) you can represent the value of the pixel in the position (ij) as a binary number this binary can be then divided in all of its bit so that you will have a most significant bit (the one that contains quite a lot of information and a least significant bit that contains few information)

Quantisation watermarking - A new method for watermarking based on vector quantisation is proposed It is efficient for implementation with conventional techniques and simulation results show its robustness under a variety of attacks It also represents superiority over existing algorithms

Wavelet transform domain algorithms - The wavelet transform-domain least-mean square (WTDLMS) algorithm is known to have in general a faster convergence rate than the time-domain LMS algorithm and can find many applications in signal processing and communications areas However the computational complexity of the wavelet filter bank is relatively high In this work we show how to exploit the redundancy which exists in the computation of the wavelet coefficients between successive iterations so as to significantly reduce the computational load of the algorithm

Page | 17

7 Applications of Digital Watermarking

There is a wide variety of applications for watermarking The requirements of watermarking systems are always based on the application as for obvious reasons there is no ldquouniversalrdquo watermarking method Although it has to be robust in general different level of required robustness can be identified besides the specific characteristics of the problem which make the watermarking a suitable solution Several applications are listed below

Owner identification ndash similar to copyright protection to establish ownership of the content

Copy protection ndash also known as copy control to prevent people from making illegal copies of copyrighted content

Content authentication ndash to detect modifications of the content as a sign of invalid authentication

Fingerprinting ndash sometimes referred as transaction tracking or traitor tracking to trace back illegal duplication and distribution of the content

Broadcast monitoring ndash specifically for advertisements and in entertainment industries to monitor content being broadcasted as contracted and by the authorized source

Medical applications ndash known as invertible watermarking to provide both authentication and confidentiality in a reversible manner without affecting the medical image in any way

Page | 18

8 Limitations of digital watermarking

In January 1997 a counterfeiting scheme has been demonstrated for a class of invertible feature-based frequency domain invisible watermarking algorithms This counterfeiting scheme could be used to subvert ownership claims because the recovery of the digital signature from a watermarked image requires a comparison with an original The counterfeiting scheme works by first creating a counterfeit watermarked copy from the genuine watermarked copy by effectively inverting the genuine watermark This inversion creates a counterfeit of the original image A comparison of the decoded versions of both yield the owners (authorized) and the forged (inverted) signature This the technique of establishing legitimate ownership recovering the signature watermark by comparing a watermarked image with the original image breaks down It can be shown that both the legitimate signature and counterfeiters signature inhere in both the watermarked and counterfeit watermarked copies Thus while it may be demonstrated that at least one recipient has a counterfeit watermarked copy it cannot be determined which it is

Page | 19

9 Proposed Work

In traditional symmetric watermarking schemes the key used for watermark embedding must be available at the watermark detector This leads to a security problem if the detectors are implemented in consumer devices that are spread all over the world So asymmetric watermarking schemes also named public key digital watermarking schemes attract more and more attentions In such a public key watermarking system the private key is used for watermarking embedding and the public key is used only for watermarking detection The private key is kept for secret and the watermarks cannot easily be removed with public key

We are actually concentrating on studying public key watermarking techniques to evaluate and compare their performance in comparison to private key water marking techniques

Page | 20

10 RESEARCH DIRECTIONS

101 Study on Watermarking Algorithm

Digital watermarking technology processing contains two cores watermark embedding algorithm and detection algorithm Robustness imperceptibility invisibility and security of digital watermarking is generally the focus of the requirements

102 Study on Watermarking Theory

Although there are many published articles on watermarking the current watermarking technology canrsquot yet fill the actual requirements of most users The lack of standards interoperability problems as well as a suit of accurate and realistic requirements to watermarking system is still hinder the development of digital watermarking technology

There are still many problems to be resolved In order to be more widely used digital watermarking should establish a series of standards or agreements such as the standards of watermark embedding detection and certification Different watermarking algorithm has different compatibility and that is obviously not conducive to promoting the application of digital watermarking

103 Study on Watermark Attack

The relationship between watermark attack and watermarking algorithm is the same as spear and shield they restrict each other and promote each other as well To develop the technologies combined with cryptography authentication and digital signature is probably the direction of resistance development to various attacks

Page | 21

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

7 Applications of Digital Watermarking

There is a wide variety of applications for watermarking The requirements of watermarking systems are always based on the application as for obvious reasons there is no ldquouniversalrdquo watermarking method Although it has to be robust in general different level of required robustness can be identified besides the specific characteristics of the problem which make the watermarking a suitable solution Several applications are listed below

Owner identification ndash similar to copyright protection to establish ownership of the content

Copy protection ndash also known as copy control to prevent people from making illegal copies of copyrighted content

Content authentication ndash to detect modifications of the content as a sign of invalid authentication

Fingerprinting ndash sometimes referred as transaction tracking or traitor tracking to trace back illegal duplication and distribution of the content

Broadcast monitoring ndash specifically for advertisements and in entertainment industries to monitor content being broadcasted as contracted and by the authorized source

Medical applications ndash known as invertible watermarking to provide both authentication and confidentiality in a reversible manner without affecting the medical image in any way

Page | 18

8 Limitations of digital watermarking

In January 1997 a counterfeiting scheme has been demonstrated for a class of invertible feature-based frequency domain invisible watermarking algorithms This counterfeiting scheme could be used to subvert ownership claims because the recovery of the digital signature from a watermarked image requires a comparison with an original The counterfeiting scheme works by first creating a counterfeit watermarked copy from the genuine watermarked copy by effectively inverting the genuine watermark This inversion creates a counterfeit of the original image A comparison of the decoded versions of both yield the owners (authorized) and the forged (inverted) signature This the technique of establishing legitimate ownership recovering the signature watermark by comparing a watermarked image with the original image breaks down It can be shown that both the legitimate signature and counterfeiters signature inhere in both the watermarked and counterfeit watermarked copies Thus while it may be demonstrated that at least one recipient has a counterfeit watermarked copy it cannot be determined which it is

Page | 19

9 Proposed Work

In traditional symmetric watermarking schemes the key used for watermark embedding must be available at the watermark detector This leads to a security problem if the detectors are implemented in consumer devices that are spread all over the world So asymmetric watermarking schemes also named public key digital watermarking schemes attract more and more attentions In such a public key watermarking system the private key is used for watermarking embedding and the public key is used only for watermarking detection The private key is kept for secret and the watermarks cannot easily be removed with public key

We are actually concentrating on studying public key watermarking techniques to evaluate and compare their performance in comparison to private key water marking techniques

Page | 20

10 RESEARCH DIRECTIONS

101 Study on Watermarking Algorithm

Digital watermarking technology processing contains two cores watermark embedding algorithm and detection algorithm Robustness imperceptibility invisibility and security of digital watermarking is generally the focus of the requirements

102 Study on Watermarking Theory

Although there are many published articles on watermarking the current watermarking technology canrsquot yet fill the actual requirements of most users The lack of standards interoperability problems as well as a suit of accurate and realistic requirements to watermarking system is still hinder the development of digital watermarking technology

There are still many problems to be resolved In order to be more widely used digital watermarking should establish a series of standards or agreements such as the standards of watermark embedding detection and certification Different watermarking algorithm has different compatibility and that is obviously not conducive to promoting the application of digital watermarking

103 Study on Watermark Attack

The relationship between watermark attack and watermarking algorithm is the same as spear and shield they restrict each other and promote each other as well To develop the technologies combined with cryptography authentication and digital signature is probably the direction of resistance development to various attacks

Page | 21

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

8 Limitations of digital watermarking

In January 1997 a counterfeiting scheme has been demonstrated for a class of invertible feature-based frequency domain invisible watermarking algorithms This counterfeiting scheme could be used to subvert ownership claims because the recovery of the digital signature from a watermarked image requires a comparison with an original The counterfeiting scheme works by first creating a counterfeit watermarked copy from the genuine watermarked copy by effectively inverting the genuine watermark This inversion creates a counterfeit of the original image A comparison of the decoded versions of both yield the owners (authorized) and the forged (inverted) signature This the technique of establishing legitimate ownership recovering the signature watermark by comparing a watermarked image with the original image breaks down It can be shown that both the legitimate signature and counterfeiters signature inhere in both the watermarked and counterfeit watermarked copies Thus while it may be demonstrated that at least one recipient has a counterfeit watermarked copy it cannot be determined which it is

Page | 19

9 Proposed Work

In traditional symmetric watermarking schemes the key used for watermark embedding must be available at the watermark detector This leads to a security problem if the detectors are implemented in consumer devices that are spread all over the world So asymmetric watermarking schemes also named public key digital watermarking schemes attract more and more attentions In such a public key watermarking system the private key is used for watermarking embedding and the public key is used only for watermarking detection The private key is kept for secret and the watermarks cannot easily be removed with public key

We are actually concentrating on studying public key watermarking techniques to evaluate and compare their performance in comparison to private key water marking techniques

Page | 20

10 RESEARCH DIRECTIONS

101 Study on Watermarking Algorithm

Digital watermarking technology processing contains two cores watermark embedding algorithm and detection algorithm Robustness imperceptibility invisibility and security of digital watermarking is generally the focus of the requirements

102 Study on Watermarking Theory

Although there are many published articles on watermarking the current watermarking technology canrsquot yet fill the actual requirements of most users The lack of standards interoperability problems as well as a suit of accurate and realistic requirements to watermarking system is still hinder the development of digital watermarking technology

There are still many problems to be resolved In order to be more widely used digital watermarking should establish a series of standards or agreements such as the standards of watermark embedding detection and certification Different watermarking algorithm has different compatibility and that is obviously not conducive to promoting the application of digital watermarking

103 Study on Watermark Attack

The relationship between watermark attack and watermarking algorithm is the same as spear and shield they restrict each other and promote each other as well To develop the technologies combined with cryptography authentication and digital signature is probably the direction of resistance development to various attacks

Page | 21

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

9 Proposed Work

In traditional symmetric watermarking schemes the key used for watermark embedding must be available at the watermark detector This leads to a security problem if the detectors are implemented in consumer devices that are spread all over the world So asymmetric watermarking schemes also named public key digital watermarking schemes attract more and more attentions In such a public key watermarking system the private key is used for watermarking embedding and the public key is used only for watermarking detection The private key is kept for secret and the watermarks cannot easily be removed with public key

We are actually concentrating on studying public key watermarking techniques to evaluate and compare their performance in comparison to private key water marking techniques

Page | 20

10 RESEARCH DIRECTIONS

101 Study on Watermarking Algorithm

Digital watermarking technology processing contains two cores watermark embedding algorithm and detection algorithm Robustness imperceptibility invisibility and security of digital watermarking is generally the focus of the requirements

102 Study on Watermarking Theory

Although there are many published articles on watermarking the current watermarking technology canrsquot yet fill the actual requirements of most users The lack of standards interoperability problems as well as a suit of accurate and realistic requirements to watermarking system is still hinder the development of digital watermarking technology

There are still many problems to be resolved In order to be more widely used digital watermarking should establish a series of standards or agreements such as the standards of watermark embedding detection and certification Different watermarking algorithm has different compatibility and that is obviously not conducive to promoting the application of digital watermarking

103 Study on Watermark Attack

The relationship between watermark attack and watermarking algorithm is the same as spear and shield they restrict each other and promote each other as well To develop the technologies combined with cryptography authentication and digital signature is probably the direction of resistance development to various attacks

Page | 21

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

10 RESEARCH DIRECTIONS

101 Study on Watermarking Algorithm

Digital watermarking technology processing contains two cores watermark embedding algorithm and detection algorithm Robustness imperceptibility invisibility and security of digital watermarking is generally the focus of the requirements

102 Study on Watermarking Theory

Although there are many published articles on watermarking the current watermarking technology canrsquot yet fill the actual requirements of most users The lack of standards interoperability problems as well as a suit of accurate and realistic requirements to watermarking system is still hinder the development of digital watermarking technology

There are still many problems to be resolved In order to be more widely used digital watermarking should establish a series of standards or agreements such as the standards of watermark embedding detection and certification Different watermarking algorithm has different compatibility and that is obviously not conducive to promoting the application of digital watermarking

103 Study on Watermark Attack

The relationship between watermark attack and watermarking algorithm is the same as spear and shield they restrict each other and promote each other as well To develop the technologies combined with cryptography authentication and digital signature is probably the direction of resistance development to various attacks

Page | 21

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

Fig 11 attacks on digital water marking

Page | 22

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

104 Study on Evaluation System of Watermarking Technology

Most of the watermarking system evaluation are empirical so it is necessary to improve the theoretical evaluation system of watermarking technology establish the watermark testing and evaluation standards and design an evaluation system for fair comparison and evaluation of various watermarking algorithms

Digital watermarking technology closely related to information security information hiding cryptography and authentication technologies s is a cutting edge research area of the international academic research in recent years

In nowadays the rapid development of network of information and e-commerce make digital watermarking technology very important for all forms of digital products protection and its application is becoming increasingly widespread All these set higher demands for people to design a better watermarking algorithm It must be recognized that digital watermarking technology needs to be combined with these disciplines and technologies so as to resist all kinds of attacks and form integrated solutions for digital productsrsquo copyright protection

Page | 23

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

11 Conclusion

Digital watermarking have been used in last few year to protect the ownership of digital data Various technique develop make use of human audio visual system Information security and copyright protection are more important today than before Digital watermarking is one of the widely used techniques used in the world in the area of information security

Digital watermarking is an exciting new field It is exciting for researchers because it is a new field and there is an opportunity to do pioneering work It is exciting for entertainment companies museums and libraries because it offers the promise of better protecting their multimedia content from piracy It is exciting for consumers because better multimedia protection could lead to cheaper better and more freely available entertainment and educational materials

However the excitement about the promise of watermarking should not mask the state of its ful fillment In spite of the exaggerated claims often made about digital watermarking it is a new field Many applications have been proposed for watermarking most of them remain unproven Few careful examinations of the technical requirements of the proposed applications have been undertaken A common application requirement is that the watermark resist attacks that would remove it (or insert a false watermark)

Page | 24

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking

12 References

[1] FAPPetitcolasRJAndersonMGKuhn Information hidingmdashA survey[J] Proceeding of IEEE 199987(7) 1062-1078 [2] GVoyatzis IPitas The use of watermarks in the protection of digital multimedia products [J] Proceeding of IEEE 199987(7) 1197-1207

[3] Ding Huang and Hong Yan ldquoInterword Distance Changes Represented by Sine Waves for Watermarking Text Imagesrdquo IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FORVIDEOTECHNOLOGY VOL 11 NO 12 DECEMBER 20011237[4] G S Peake and T N Tan ldquoA general algorithm for document skew angle estimationrdquo in Proc of lCIPrsquo97 IEEE lnt Con$ Image Proc SBarbara CA October 26-29 1997 vol 11 pp 230-233

[4] Y M Y Hasan and L J Karam ldquoMorphological text extraction from imagesrdquo IEEE Trans lmage Proc vol9 no 11 pp 1978-1983 November 2000

[5] Kim Young-Won Moon Kyung-Ae Oh Il-Seok ldquoA Text Watermarking Algorithm Based on Word Classification and InterwordrdquoIn 1063398 Proceedings of the Seventh International

Page | 25

• 3 Requirements of watermarks
• To be effective in the protection of the ownership of intellectual property the invisibly watermarked image should satisfy several criteria
• 6 Digital Watermarking Techniques
• 64 Video Watermarking
• 61Text-Based Watermarking Techniques
• • The Discrete Cosine Transform (DCT)
  • • 8 Limitations of digital watermarking