MPEG 4Shaojie ZhangAnjum Gupta

Dept. of Computer Science and Engineering

Outline

• Overview

• Technical Detail

• Industry and Market

• Conclusion

Overview

• MPEG-1 - Error free environments

• MPEG-2 - Broadcast TV (SD and HD)

• MPEG-4 - Object based coding

• MPEG-7 - Multimedia description

• MPEG-21 - Seven element initiative for multimedia deployment

What is MPEG-4

• An open toolbox to build bitstreams and decoders for multimedia content:

• Synthetic interactive graphics content

• To accommodate various user devices

• Lower bit rate encoding

MPEG 4 – Basic Approach

• Object Based Encoding– MPEG-4 audiovisual scenes are composed of

several media objects.• Still objects (e.g. fixed background)

• Video objects (e.g. a talking person) • Audio objects

Encoding Example

An example of an MPEG-4 Scene

Scene Description Format

• An MPEG-4 scene structure is represented as a DAG.

• Each node is a media object.

• Multiplexed with the media objects.

Flexibility within MPEG-4

• Various algorithms to handle special cases.

• The stream is made of atomic units called Video Objects (VOs).

• Audio Visual Objects (AVOs) are combined to create a scene.

Bit rate variability

Generic coder is extended by adding “Shape” input.

Coding Tools and Algorithms

VLBV (Very Low Bit-rate Video) core can be extended by adding more information.

MPEG-4 Encoding

Decoding

An Application

Companies having MPEG-4 products

• Index of Companies

1. Ahead Software 2. Amphion Semiconductor 3. Apple Computers4. Bitmanagement

Software GmbH 5. Dicas

Digital Image Coding GmbH 6. DivXNetworks, Inc. 7. Emblaze Research 8. Envivio 9. Equator Technologies, Inc. 10.Fraunhofer Institute IIS-A 11.Hantro Products Oy 12.Harmonic Inc. 13.iVAST Inc.

14.Nextreaming Corporation 15.Octaga AS 16.Philips Electronics 17.Prodys 18.Sci-worx GmbH 19.Sorenson Media 20.Soundball, Inc. 21.Toshiba 22.Tvia, Inc. 23.VBrick Systems, Inc. 24.VCS Video Communication Syst

ems AG 25.VideoSpheres Inc. 26.Xilinx Inc.

MPEG Market Penetration

US Market Penetration – growth from year 0 (introduction) – 10(From: The Yankee Group).

MPEG Media Distribution

US Video-On-Demand Subscriber Forecasts(From: The Yankee Group)

MPEG 4 Vs Other Technologies

Conclusion

• MPEG-4 enables very low bit-rate multimedia communications.

• MPEG-4 is a dynamic standard, that is continuously being improved.

• Is being accepted in the industry applications.

• Expanding demand in the market.

References

• ISO/IEC JTC1/SC29/WG11 N4668

• ISO/IEC JTC 1/SC 29/WG 11N2826

• ISO/IEC JTC 1/SC 29/WG 11N5504

• MPEG-4 Industry Forum (http://www.m4if.org)

Acknowledgement

• Dr. Wo Chang, NIST, U.S.

• Dr. Kai-Kuang Ma, NTU, Singapore