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8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 1/35
Steganography
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 2/35
AgendaWhat is Steganography?
Steganography Techniques.
Hierarchy.
Steganography VS Cryptography.Data hiding VS watermarking.
What is Steganalysis?
Categorizes of Steganalysis.Applications.
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 3/35
Agenda
What is Steganography? Steganography Techniques.
Hierarchy.
Steganography VS Cryptography.Data hiding VS watermarking.
What is Steganalysis?
Categorizes of Steganalysis.
Applications.
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 4/35
What is Steganography ??
It is a Greek word.
Steganós (Stegano) Covered orprotected
Graphei (Graphy) writing
Stegano - Graphy Covered Writing.
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 5/35
What is Steganography ??
Practice of hiding information within
other information
Is the art and science of writing hidden
messages in such a way that no one, apart
from the sender and intended recipient,
suspects the existence of the message.
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 6/35
AgendaWhat is Steganography?
Steganography Techniques.
Hierarchy.
Steganography VS Cryptography.Data hiding VS watermarking.
What is Steganalysis?
Categorizes of Steganalysis.
Applications.
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 7/35
Physical Steganography Past
Digital Steganography
Network Steganography
Audio Steganography
E-Text Steganography
Steganography techniques
Current
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 8/35
Physical Steganography
The first recorded uses of Steganographycan be traced back to 440 BC.
Wax tablets.
Messenger's body.(drawbacks)
Secret ink.
Text messages.
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 9/35
Physical Steganography cont’d text Steganography
News Eight Weather: Tonight increasing
snow. Unexpected precipitation Smothers
Eastern t owns. Be extremely cautious and
use snow t ires especially heading east. Thehighways are k nowingly slippery. Highway
evacuation is suspected. Police report
emergency situations in downtown ending
near Tuesday
First letter of each word yields: Newt is
upset because he thinks he is President
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 10/35
Modern Steganography entered theworld in 1985.
The boom of Steganography coincideswith the appearance of the Internet.
Images , videos, etc.
Digital Steganography
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 11/35
Image of a tree with a steganographically hiddenimage. The hidden image is revealed by removing allbut the two least significant bits of each color
component and a subsequent normalization.
Digital Steganography cont’d
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 12/35
Digital Steganography cont’d
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 13/35concealing
Why LSB ???
Digital Steganography cont’d
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 14/35
Why LSB????
10000001
LSB MSB
(10000001)2
= (129)10
(10000000)2 = (128)10
00000001
10000000
(00000001)2 = (1)10
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 15/35Revealing
Digital Steganography cont’d
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 16/35
Network Steganography
Is a part of information hiding focused on modernnetworks and is a method of hiding secret data inusers' normal data transmissions, ideally, so it
cannot be detected by third parties.
EX: LACK ( Lost Audio Packets Steganography).
8/3/2019 Steganography Final
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Network Steganography cont’d
LACK
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 18/35
Audio Steganography
Audio Steganography requires a text oraudio secret message to be embeddedwithin a cover audio message. Due toavailability of redundancy, the cover audiomessage before Steganography and thestego message after Steganographyremains the same.
Methods: LSB coding, Parity coding,Phase coding, Spread spectrum, Echohiding.
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 19/35
Audio Steganography
cont’d
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 20/35
Audio Steganography cont’d
LSB coding
8/3/2019 Steganography Final
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text Steganography is considered to bethe most difficult kind of Steganographydue to the lack of redundancy in text as
compared to image or audio. However, itrequires less memory and provides forsimpler communication.
E-Text Steganography
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 22/35
AgendaWhat is Steganography?
Steganography Techniques.
Hierarchy.
Steganography VS Cryptography.Data hiding VS watermarking.
What is Steganalysis?
Categorizes of Steganalysis.
Applications.
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 23/35
Hierarchy
Secret writing
Protection against detection
(data hiding)
Protection against removal
(document marking)
Watermarking
Fingerprinting
Steganography Cryptography
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 24/35
AgendaWhat is Steganography?
Steganography Techniques.
Hierarchy.
Steganography VS Cryptography.Data hiding VS watermarking.
What is Steganalysis?
Categorizes of Steganalysis.
Applications.
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 25/35
Steganography VS Cryptography
Steganography Cryptography
•The message may not be difficult to
decode
•Most people would not detect the
presence of the message.
•Cryptography is hiding the content
of the message, but not the
existence of the message.
•one cannot decode the message
without knowing the proper key.•one can tell that a message has
been encrypted.
8/3/2019 Steganography Final
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Why Steganography?
Encrypted messages are obvious ,usingSteganography we can hide them in other
innocuous looking objects so that their very
presence is not revealed.
Thus, Steganography can be a feasible
alter- native in countries where usage of encryption is illegal (China, Russia, Iran,
Iraq ,...).
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 27/35
AgendaWhat is Steganography?
Steganography Techniques.
Hierarchy.
Steganography VS Cryptography.Data hiding VS watermarking.
What is Steganalysis?
Categorizes of Steganalysis.
Applications.
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 28/35
Data hiding VS Watermarking
Steganography (data hiding) Watermarking
Adding a hidden message to an image or other
media file.
Similar to encrypting a document, but instead
of running it through a cipher, the document is
broken up and stored in unused, or
unnoticeable, bits within the overall image.
Similar to steganography BUT
has a completely different purpose.
Placing a watermark in an image or other media
file serves to identify the artist or author of the
work. So, it isn’t for the purpose of hiding data.
Watermarking is used to protect the copyright
of the original owner, to make their claim
stronger, should the image be used without
permission by someone else.
So, the main goal of Steganography is to hide a
message m in some audio or video (cover) data
d, to obtain new data d', practicallyindistinguishable from d, by people, in such a
way that an eavesdropper cannot detect the
presence of m in d'.
So, the main goal of watermarking is to hide a
message m in some audio or video (cover) data
d, to obtain new data d', practicallyindistinguishable from d, by people, in such a
way that an eavesdropper cannot remove or
replace m in d‘.
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 29/35
AgendaWhat is Steganography?
Steganography Techniques.
Hierarchy.
Steganography VS Cryptography.Data hiding VS watermarking.
What is Steganalysis?
Categorizes of Steganalysis.
Applications.
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 30/35
Steganalysis
What is Steganalysis ?
Steganalysis is the discovery of theexistence of hidden information; therefore,
like cryptography and cryptanalysis.
The goal: is to discover hiddeninformation and to break the security ofits carriers ( the files which have hiddeninformation inside of them).
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 31/35
AgendaWhat is Steganography?
Steganography Techniques.
Hierarchy.
Steganography VS Cryptography.Data hiding VS watermarking.
What is Steganalysis?
Categorizes of Steganalysis.Applications.
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 32/35
Steganalysis algorithms can becategorized as:
Targeted Steganalysis :○ is one that is designed to detect stego Works that are
created by one or more particular steganographic methods. This provides a powerful clue with which to choose the feature representation.
Blind Steganalysis:○ If the method of detection is independent of the
Steganography method used.
the knowledge of the steganographic algorithm used.
It depends on
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 33/35
AgendaWhat is Steganography?
Steganography Techniques.
Hierarchy.
Steganography VS Cryptography.Data hiding VS watermarking.
What is Steganalysis?
Categorizes of Steganalysis.
Applications.
8/3/2019 Steganography Final
http://slidepdf.com/reader/full/steganography-final 34/35
Applications
1. Access control system for digital
content distribution. Publishing digital contents on the web and
limiting the controlling the access of thosecontents.
2. Usage in modern printers. Barely visible tiny yellow dots are added to each
page encoded printer serial numbers, date and
time stamps.
8/3/2019 Steganography Final
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References http://www.datahide.com/BPCSe/applications-e.html
http://en.wikipedia.org/wiki/Steganography http://stegano.net/workshop/
http://arxivblog.com/?m=200811
http://stegano.net/tutorial.html
http://www.snotmonkey.com/work/school/405/methods.html#echo
http://mynetworksecurity.files.wordpress.com/2010/06/audio-steg.png
http://wajdyessam.sudancs.com/?p=159
http://www.datahide.com/BPCSe/applications-e.html
http://en.wikipedia.org/wiki/Steganography#Applications
Web-based Multimedia Steganography System – Paper. Digital Watermarking and Steganography – Second Edition