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Multimedia Technologies

Faculty Name :Bharat Bhushan NaibDesignation : Assistant Professor

Department : Computer Science & EngineeringE-mail id : bharatnaib@gmail.com

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ASSESSMENT CRITERIA

1. One Class Test 20 Marks

2. One Assignment and Presentation 10Marks

3.Class Performance 10 Marks

4. Attendance 10 Marks

Less than 50% 2 Marks

50% to 60% 4 Marks

61% to 70% 6 Marks

71% to 80% 8 Marks

Above 80% 10 MarksPDM CSE

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Guideline for Students

• Multimedia is an ever growing and an interesting field which is of huge demand to

content developers and web designers.. Multimedia is an important part of the

undergraduate curriculum for many reasons:

(1) It provides students with a better understanding of and appreciation for different

form of communication (text, graphics, animation, audio and video etc.).

(2) it offers an excellent combination of creative and technical thinking. Students will

gain knowledge and skills in web and rich internet application development,

animation, 3D-modelling and video production.

(3) It provides motivation for the study of an interesting topic such as Virtual Reality.

(4) It is a good vehicle for an extended knowledge about different communication

media.PDM CSE

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Syllabus

  Section-A

Basics of Multimedia Technology: Computers, communication and entertainment; multimedia an

introduction; framework for multimedia systems; multimedia devices; CD- Audio, CD-ROM, CD-I,

presentation devices and the user interface; multimedia presentation and authoring; professional

development tools; LANs and multimedia; internet, World Wide Web & multimedia distribution

network-ATM & ADSL; multimedia servers & databases; vector graphics; 3D graphics programs;

animation techniques; shading; anti aliasing; morphing; video on demand.

  Section-B

Image Compression & Standards: Making still images; editing and capturing images; scanning

images; computer color models; color palettes; vector drawing; 3D drawing and rendering; JPEG-

objectives and architecture; JPEG-DCT encoding and quantization, JPEG statistical coding, JPEG

predictive lossless coding; JPEG performance; overview of other image file formats as GIF, TIFF,

BMP, PNG etc.

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Syllabus

Section-C

Audio & Video: Digital representation of sound; time domain sampled representation ;method of

encoding the analog signals; sub band coding; Fourier method; transmission of digital sound;

digital audio signal processing; stereophonic & quadraphonic signal processing; editing sampled

sound; MPEG Audio; audio compression & decompression; brief survey of speech recognition

and generation; audio synthesis; musical instrument digital interface; digital video and image

compression; MPEG motion video compression standard; DVI technology; time base media

representation and delivery.

  Section-D

Virtual Reality: Applications of multimedia, intelligent multimedia system, desktop virtual

reality, VR operating system, virtual environment displays and orientation making; visually

coupled system requirements; intelligent VR software systems. Applications of environment in

various fields.

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Multimedia Technologies

Section-A

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Multimedia an Introduction

• Multimedia is media and content that uses a combination of

different content forms. The term can be used as a noun (a medium

with multiple content forms) or as an adjective describing a medium

as having multiple content forms. The term is used in contrast to

media which use only rudimentary computer display such as text-

only, or traditional forms of printed or hand-produced material.

Multimedia includes a combination of text, audio, still

images, animation, video, or interactivity content forms.

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Multimedia an Introduction

• Multimedia is usually recorded and played, displayed or accessed

by information content processing devices, such as computerized and

electronic devices, but can also be part of a live

performance. Multimedia (as an adjective) also describes electronic

media devices used to store and experience multimedia content.

Multimedia is distinguished from mixed media in fine art; by including

audio, for example, it has a broader scope. The term "rich media" is

synonymous for interactive multimedia. Hypermedia can be considered

one particular multimedia application.

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Classification of Multimedia

• Multimedia may be broadly divided into linear and non-linear categories.

Linear active content progresses often without any navigational control for

the viewer such as a cinema presentation. Non-linear uses interactivity to

control progress as with a video game or self-paced computer based

training. Hypermedia is an example of non-linear content.

• Multimedia presentations can be live or recorded. A recorded presentation

may allow interactivity via a navigation system. A live multimedia

presentation may allow interactivity via an interaction with the presenter or

performer.

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Major Characteristics of Multimedia

• Multimedia presentations may be viewed by person

on stage, projected, transmitted, or played locally with a media player. A

broadcast may be a live or recorded multimedia presentation. Broadcasts

and recordings can be either analog or digital electronic media technology.

Digital online multimedia may be downloaded or streamed. Streaming

multimedia may be live or on-demand.

• Multimedia games and simulations may be used in a physical environment

with special effects, with multiple users in an online network, or locally

with an offline computer, game system, or simulator.

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• The various formats of technological or digital multimedia may be

intended to enhance the users' experience, for example to make it

easier and faster to convey information or in entertainment or art, to

transcend everyday experience.

• Including audio cues for where video-conference participants are

located.

• Building searchable features into new video, and enabling very high-

to very low-bit-rate use of new, scalable multimedia products.

Major Characteristics of Multimedia Cont..

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Major Characteristics of Multimedia Cont..

• Making multimedia components editable.

• Building “inverse-Hollywood” applications that

can recreate the process by which a video was

made.

• Using voice-recognition to build an interactive

environment, say a kitchen-wall web browser.

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World Wide Web

• The W3C has listed the following goals for the WWW:

1. Universal access of web resources (by everyone everywhere).

2. Effectiveness of navigating available information.

3. Responsible use of posted material.

• History of the WWW

1960s – Charles Goldfarb et al. developed the Generalized Markup Language (GML) for IBM.

1986 – The ISO released a final version of the Standard Generalized Markup Language (SGML).

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• 1990 – Tim Berners-Lee invented the HyperText Markup Language (HTML), and the HyperText Transfer Protocol (HTTP).

• 1993 – NCSA released an alpha version of Mosaic based on the version by Marc Andreessen for X-Windows — the first popular browser.

• 1994 – Marc Andreessen et al. formed Mosaic Communications Corporation — later the Netscape Communications Corporation.

• 1998 – The W3C accepted XML version 1.0 specifications as a Recommendation — the main focus of the W3C and supersedes HTML.

World Wide Web Cont…

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MULTIMEDIA AUTHORING

• Multimedia authoring involves collating, structuring and presenting information in

the form of a digital multimedia, which can incorporate text, audio, and still and

moving images.

• Authoring involves collating, structuring and presenting information in the form of

a document created in some medium or media. Traditionally this has been applied

to the production of static text documents. With the advent of digital multimedia

systems – that can incorporate text, audio, and still and moving images – authoring

process has become much more complex. Interactive multimedia systems allow the

user to change the presented content, and therefore, add another level of complexity

to the authoring process.

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MULTIMEDIA AUTHORING Cont…

• The driving force behind all authoring is the human need to communicate.

Verbal, pictorial, sign and written languages have provided the means to

communicate meaning since time immemorial. Today we can employ

multimedia systems to combine text, audio, still and moving images to

communicate. Computer-based digital multimedia systems not only

provide the means to combine these multiple media elements seamlessly,

but also offer multiple modalities for interacting with these elements. The

cross-product of these multiple elements and modalities gives rise to a very

large number of ways in which these can be combined.

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Multimedia Authoring Tools

• Macromedia Flash: allows users to create interactive movies

by using the score metaphor, i.e., a timeline arranged in

parallel event sequences.

• Macromedia Director: uses a movie metaphor to create

interactive presentations — very powerful and includes a

built-in scripting language, Lingo, that allows creation of

complex interactive movies.

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Multimedia Authoring Tools Cont….

• Authorware: a mature, well-supported authoring product based

on the Iconic/Flow-control metaphor.

• Quest: similar to Authorware in many ways, uses a type of

flowcharting metaphor. However, the flowchart nodes can

encapsulate information in a more abstract way (called

frames) than simply subroutine levels.

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FRAMEWORK FOR MULTIMEDIA SYSTEMS

• A multimedia framework is a software framework that handles media on a computer and through a network. A good multimedia framework offers an intuitive API and a modular architecture to easily add support for new audio, video and container formats and transmission protocols. It is meant to be used by applications such as media players and audio or video editors, but can also be used to build videoconferencing applications, media converters and other multimedia tools.

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FRAMEWORK FOR MULTIMEDIA SYSTEMS Cont….

• In contrast to function libraries, a multimedia framework provides a run time environment for the media processing. Ideally such an environment provides execution contexts for the media processing blocks separated from the application using the framework. The separation supports the independent processing of multimedia data in a timely manner. These separate contexts can be implemented as threads.

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COMPACT DISC

• Compact Disc - Digital Audio (CD-DA), the original CD specification developed by Philips and Sony in 1980

• Specifications were published in Red Book, continued to be updated (lastest version in 1999)

• In 1985 a standard for the storage of computer data by Sony and Philips, CD-ROM (Compact Disc Read Only Memory)

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Compact Disc Cont….

• Developments in the technology have been ongoing

and rapid

– Compact disc Interactive (CD-I)

– Compact Disc Television (CD-TV)

– Compact Disc Recording (CD-R)

– Digital Video Disc (DVD)

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Compact Disc Cont…

• A CDROM Drive uses a small plastic-encapsulated

disk that can store data

• This information is retrieved using a Laser Beam

• A CD can store vast amounts of information because

it uses light to record data in a tightly packed form

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• The Beginning 1975 – 1985– Laser Disc ( 300 mm / 30 min)

• 30 cm discs with analog video• Philips standard ISO/IEC standard

– 12” WORM (300 mm / 1.25 GByte)• 12 inch discs for Write Once data recording• Direct ISO/IEC standard

– 5 ¼ “ MO ( 130 mm / 650 Mbyte )• 130 mm discs for Read & Write date recording• Ecma ISO/IEC Standard

– 90 mm MO disc (90 mm / 128 MByte )• 90 mm discs for Read & Write data recording• Ecma ISO/IEC standard

Compact Disc Cont….

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• The Boost 1985 – 2000– Introduction of CD 1982– CD-Audio

• 120 mm disc• 74 minutes of Digital Audio

– CD-ROM• 650 Mbytes Read Only Data

– CD-R• 650 Mbytes of Recordable Data

– CD-RW• 650 Mbytes of Rewritable Data

Compact Disc Cont….

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Mature Market 2000 – 2015

Introduction of DVD in 1996

DVD-Video

2 hours of Standard Definition Video

DVD-R & DVD+R

9,4 Gbytes of Recordable Data

DVD-RAM & DVD+RW & DVD-RW

9,4 Gbytes of Rewritable Data

Compact Disc Cont….

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The last one (?) 2015 – 2025Introduction of Blu-ray Disc in 2006 BD-Video

2 hours of High Definition VideoBD-Rewritable

Single & Double Layer 25/50 GbytesTriple Layer 100 GBytes

BD-RecordableSingle & Double Layer 25/50 GbytesTriple Layer 100 GBytesQuadruple Layer 128 GBytes

Compact Disc Cont….

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1 7 38

Compact Disc Cont….

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LAN (Local Area Networks)

• A LAN is a computer network that covers a small area (home, office, building, campus)– a few kilometers

• LANs have higher data rates (10Mbps to 10Gbps) as compared to WANs• LANs (usually) do not involve leased lines; cabling and equipments belong

to the LAN owner. • A LAN consists of

– Shared transmission medium• now so valid today due to switched LANs

– regulations for orderly access to the medium– set of hardware and software for the interfacing devices

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Advantages of LAN

- Workstations can share peripheral devices like printers. This is cheaper than buying a printer for every workstation.

- User can save their work centrally on the network's file server. This means that they can retrieve their work from any workstation on the network. 

- Users can communicate with each other and transfer data between workstations very easily. 

- One copy of each application package such as a word processor, spreadsheet etc. can be loaded onto the file and shared by all users.

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Advantages of LAN Cont….

- Cost. Individually licensed copies of many popular software

programs can be costly.

- Networkable versions are available at considerable savings.

- Shared programs on a network allows for easier upgrading

of the program on one single file server, instead of upgrading

individual workstations. 

- Speed. Sharing and transferring files within Networks are

very rapid. Thus saving time, while

maintaining the integrity of the file.

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Disadvantages of LAN

- Networks are difficult to set up and need to be maintained by

skilled technicians. 

- If server develops a fault, users may not be able to run the

application programs.

- A fault in the network can cause user to lose the data.

-If the network stops operating then it may not be possible to

access various computers.

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Disadvantages of LAN Cont….

• - It is difficult to make the system secure from hackers,

novices or industrial espionage.

- Decisions on resource planning tend to become centralized.

- Networks that have grown with little thought can be

inefficient in the long term.

-As traffic increases on a network the performance degrades

unless it is designed properly.

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NETWORK TOPOLOGY

• Physical and Logical Topologies

• Topologies

– Bus

– Ring

– Star

– Extended Star

– Mesh

– Hybrid

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NETWORK TOPOLOGY Cont……

Bus Topology

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NETWORK TOPOLOGY Cont……

Bus Topology Advantages

• Inexpensive to install

• Easy to add stations

• Use less cable than other

topologies

• Works well for small

networksPDM CSE

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NETWORK TOPOLOGY Cont……

Disadvantages

No longer recommended

Backbone breaks, whole network down

Limited no of devices can be attached

Difficult to isolate problems

Sharing same cable slows response rates

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NETWORK TOPOLOGY Cont……

Ring Topology

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Ring Topology

Advantages

• Data packets travel at great speed

• No collisions

• Easier to fault find

• No terminators required

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Ring Topology

Disadvantages

Requires more cable than a bus

A break in the ring will bring it down

Not as common as the bus – less devices

available

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Star Topology

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Star Topology

Advantages

• Easy to add devices as the network expands

• One cable failure does not bring down the entire

network (resilience)

• Hub provides centralised management

• Easy to find device and cable problems

• Can be upgraded to faster speeds

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Star Topology Cont.....

• Disadvantages

A star network requires more cable than a ring or bus

network

Failure of the central hub can bring down the entire

network

Costs are higher (installation and equipment) than for

most bus networks

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Extended Star Topology

A Star Network which has

been expanded to include

an additional hub or hubs.

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Mesh Topology (Web)

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Mesh Topology

• Not common on LANs

• Most often used in WANs to interconnect LANS

• Each node is connected to every other node

• Allows communication to continue in the event of a break in

any one connection

• It is “Fault Tolerant”

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Mesh Topology

Advantages• Improves Fault

Tolerance

Disadvantages

Expensive

Difficult to install

Difficult to manage

Difficult to troubleshoot

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Hybrid Topology

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Logical Bus

• Modern Ethernet networks are Star Topologies (physically)

• The Hub is at the centre, and defines a Star Topology

• The Hub itself uses a Logical Bus Topology internally, to transmit data to all segments

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Logical Bus

Advantages

• A single node failure does not bring the

network down

• Most widely implemented topology

• Network can be added to or changed without

affecting other stationsPDM CSE

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Logical Bus Cont....

Disadvantages

Collisions can occur easily

Only one device can access the network media

at a time

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Logical Ring

• Data in a Star Topology can transmit data in a Ring

• The MAU (Multi-station Access Unit) looks like an

ordinary Hub, but data is passed internally using a

logical ring

• It is superior to a Logical Bus Hub – see later slide

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Logical Ring

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Logical Ring

Advantages

• The amount of data that can be carried in a

single message is greater than on a logical

bus

• There are no collisions

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Logical Ring Cont.....

Disadvantages

A broken ring will stop all transmissions

A device must wait for an empty token to

be able to transmit

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INTERNET

-The Internet is a global system of interconnected computer

networks that use the standard Internet protocol suite (often called

TCP/IP, although not all applications use TCP) to serve billions of

users worldwide. It is a network of networks that consists of millions of

private, public, academic, business, and government networks, of

local to global scope, that are linked by a broad array of electronic,

wireless and optical networking technologies. The Internet carries an

extensive range of information resources and services, such as the

inter-linked hypertext documents of the World Wide Web (WWW) and

the infrastructure to support email.

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INTERNET CONT……

• -Most traditional communications media including telephone, music, film,

and television are reshaped or redefined by the Internet, giving birth to new

services such as Voice over Internet Protocol (VoIP) and Internet Protocol

Television (IPTV). Newspaper, book and other print publishing are

adapting to Web site technology, or are reshaped into blogging and web

feeds. The Internet has enabled and accelerated new forms of human

interactions through instant messaging, Internet forums, and social

networking. Online shopping has boomed both for major retail outlets and

small artisans and traders. Business-to-business and financial services on

the Internet affect supply chains across entire industries.PDM CSE

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ASYNCHRONOUS TRANSFER MODE (ATM)

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• ATM can provide the following benefits:

• High-speed communication

• Connection-oriented service, similar to traditional

telephony

• Fast, hardware-based switching

ADVANTAGES OF ATM

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ADVANTAGES OF ATM Cont….

• A single, universal, interoperable network transport

• A single network connection that can reliably mix

voice, video, and data

• Flexible and efficient allocation of network

bandwidth.

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DISADVANTAGES OF ATM

• Flexible to efficiency’s expense, at present, for any one application it is usually

possible to find a more optimized technology 

• Cost, although it will decrease with time 

• New customer premises hardware and software are required 

Competition from other technologies -100 Mbps FDDI, 100 Mbps Ethernet and

fast Ethernet 

• Presently the applications that can benefit from ATM such as multimedia are

rare 

The wait, with all the promise of ATM’s capabilities many details are still in the

standards process 

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ASYMMETRIC DIGITAL SUBSCRIBER LINE (ADSL)

• Asymmetric Digital Subscriber Line (ADSL) is a type of digital subscriber

line technology, a data communications technology that enables faster data

transmission over copper telephone lines than a conventional voice

band modem can provide. It does this by utilizing frequencies that are not

used by a voice telephone call. A splitter, or DSL filter, allows a single

telephone connection to be used for both ADSL service and voice calls at

the same time. ADSL can generally only be distributed over short distances

from the telephone exchange (the last mile), typically less than 4

kilometers (2 mi), but has been known to exceed 8 kilometers (5 mi) if the

originally laid wire gauge allows for further distribution.PDM CSE

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ADSL Cont…

• At the telephone exchange the line generally terminates at

a digital subscriber line access multiplexer (DSLAM) where

another frequency splitter separates the voice band signal for

the conventional phone network. Data carried by the ADSL are

typically routed over the telephone company's data network

and eventually reach a conventional Internet Protocol network.

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ADSL Cont…

• ADSL differs from the less common symmetric digital subscriber

line (SDSL) in that bandwidth (and bit rate) is greater toward the

customer premises (known as downstream) than the reverse (known

as upstream). This is why it is called asymmetric. Providers usually

market ADSL as a service for consumers to provide Internet access in

a relatively passive mode: able to use the higher speed direction for

the download from the Internet but not needing to run servers that

would require high speed in the other direction.

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ADSL Cont…

• There are both technical and marketing reasons why ADSL is

in many places the most common type offered to home users.

On the technical side, there is likely to be more crosstalk from

other circuits at the DSLAM end (where the wires from many

local loops are close to each other) than at the customer

premises. Thus the upload signal is weakest at the noisiest part

of the local loop, while the download signal is strongest at the

noisiest part of the local loop.

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ADSL Cont…

• It therefore makes technical sense to have the DSLAM transmit at a higher bit rate than does the modem on the customer end. Since the typical home user in fact does prefer a higher download speed, the telephone companies chose to make a virtue out of necessity, hence ADSL. On the marketing side, limiting upload speeds limits the attractiveness of this service to business customers, often causing them to purchase higher cost leased line services instead. In this fashion, it segments the digital communications market between business and home users

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MULTIMEDIA SERVERS

• A media server refers either to a dedicated computer

appliance or to a specialized application software, ranging

from an enterprise class machine providing video on demand,

to, more commonly, a small personal computer or NAS

(Network Attached Storage) for the home, dedicated for

storing various digital media (meaning digital videos/movies,

audio/music, and picture files).

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MULTIMEDIA SERVERS CONT….

• By definition a media server is a device that simply stores and shares media. This

definition is vague, and can allow several different devices to be called Media

Servers. It may be a simple Network-attached storage, a Home theater PC (HTPC)

running Windows XP Media Center Edition, Media Portal or Myth TV, or a

commercial web server that hosts media for a large web site. In a home setting, a

media server acts as an aggregator of information: video, audio, photos, books, etc.

These different types of media (whether they originated on DVD, CD, digital

camera, or in physical form) are stored on the media server's hard drive. Access to

these is then available from a central location. It may also be used to run special

applications that allow the user(s) to access the media from a remote location via

the internet.

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MULTIMEDIA DATABASES

• A multimedia database is a database that hosts one or more primary media file types such

as .txt (documents), .jpg (images), .swf (videos), .mp3 (audio), etc. And loosely fall into two

main categories:

– Static media (time-independent, i.e. images and handwriting)

• Static media is literal in the sense that the media it includes does not move. Newspapers,

magazines, posters and books are all examples of static media. When advertising, businesses

will pay thousands of dollars in order to secure a page of advertisements within a popular

magazine. Many believe that the modern age is moving towards a complete online and

dynamic culture, however the payment rates for a full page in a top newspaper suggests

otherwise. Static media is still an essential part of the industry and it is still considered highly

thought of to be 'in print'.

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MULTIMEDIA DATABASES CONT…..

– Dynamic media (time-dependent, i.e. video and sound bytes)

• Dynamic media is the complete opposite of static media and includes

websites, social networking and online forums. Websites allow consumers

to interact with a business and feel much more involved with the

brand. Social network marketing online is a huge new concept. Twitter,

Facebook and LinkedIn are all proving to be an essential way of

interacting with competitors and consumers and making a brand dynamic

and exciting.

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FEATURES OF MULTIMEDIA DATABASE

• Query in Multimedia DBMS

• Charts and Graphs

• Multimedia Presentation

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ADVANTAGES OF MULTIMEDIA DATABASE

– Integrated administration of huge amounts of multimedia data

– Optimized storage

– Efficient access

– Many fold complex search possibilities

– Referential integrity of links

– Transaction protected multiuser mode

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3D COMPUTER GRAPHICS

• 3D computer graphics in contrast to 2D computer graphics are

graphics that use in three dimensional representations of

geometric data that is stored in the computer for the purposes

of performing calculations and rendering 2D images. Such

images may be for later display or for real-time viewing.

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3D COMPUTER GRAPHICS CONT….

• Despite these differences, 3D computer graphics rely on many

of the same algorithm as of 2D computer vector graphics in

the wire frame model and 2D computer raster graphics in the

final rendering display. In computer graphics software, the

distinction between 2D and 3D is occasionally blurred; 2D

applications may use 3D techniques to achieve effects such as

lighting and primarily 3D may use 2d rendering techniques.

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ANIMATION

• Animation is the rapid display of a sequence of images to

create an illusion of movement. The most common method of

presenting animation is as a motion picture or video program,

although there are other methods. This type of presentation is

usually accomplished with camera and a projector or

a computer viewing screen which can rapidly cycle through

images in a sequence.

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ANIMATION Cont….

• Animation can be made with either hand rendered art, computer generated imagery, or three-dimensional objects, e.g. puppets or clay figures, or a combination of techniques. The position of each object in any particular image relates to the position of that object in the previous and following images so that the objects each appear to fluidly move independently of one another. The viewing device displays these images in rapid succession, usually 24, 25 or 30 frames per second.

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SHADING

• Shading refers to depicting depth perception in 3D

models or illustrations by varying levels of darkness.

• Shading is a process used in drawing for depicting levels of

darkness on paper by applying media more densely or with a

darker shade for darker areas, and less densely or with a

lighter shade for lighter areas.

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SHADING CONT…..

• There are various techniques of shading including cross

hatching where perpendicular lines of varying closeness are

drawn in a grid pattern to shade an area. The closer the lines

are together, the darker the area appears. Likewise, the farther

apart the lines are, the lighter the area appears.

• Light patterns, such as objects having light and shaded areas,

help when creating the illusion of depth on paper.

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ANIMATION TECHNIQUES

• CEL SHADING• COMPUTER ANIMATION• FORWARD KINEMATICS ANIMATION• MORPH TARGET ANIMATION• ROTOSCOPING ANIMATION

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SHADING TECHNIQUES

• FLAT SHADING

• SMOOTH SHADING

-GOURAUD SHADING

-PHONG SHADING

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ANTI-ALIASING

Aliasing occurs because real-world objects have

continuous, smooth curves and lines, whereas

monitors can only display discrete points of light

called pixels. Since pixels are uniformly colored

and always of the same shape, lines become

jagged.

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• Super sampling is an anti-aliasing technique, the process of

eliminating jagged and pixelated edges (aliasing). It is a

method of smoothing images rendered in computer games or

other programs that generate imagery.

• Multi sample anti-aliasing (MSAA) is a type of anti-aliasing,

a technique used in computer graphics to improve image

quality.

ANTI-ALIASING Cont…

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• Pre filtering anti aliasing: Pre filtering methods

treat a pixel as an area, and compute pixel color based

on the overlap of the scene's objects with a pixel's

area. These techniques compute the shades of gray

based on how much of a pixel's area is covered by an

object.

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84

VIDEO ON DEMAND

• Video on Demand (VOD) or Audio and Video on

Demand (AVOD) are systems which allow users to select and

watch/listen to video or audio content on

demand. IPTV technology is often used to bring video on

demand to televisions and personal computers.

PDM CSE

85

VOD Cont……

ADVANTAGES OF VOD

• Copper lines are already installed in across the U.S. and the world.

• Easily provides enough bandwith to carry full motion video and leaves

room for expansion.

• Relatively cheap compared to fiber optic cable to implement.

• No cables are used on a local level, easy to provide Near Video On

Demand to rural areas.

PDM CSE

86

VOD Cont……

DISADVANTAGES OF VOD

•  Bandwidth is relatively low as compared to fiber/coax. 

• Very expensive to implement. 

• Bandwidth is smaller as compared to fiber optic cable. 

• Cost of launching dish, does not provide true Video On

Demand.

PDM CSE