Joint Source-Channel Coding for MPEG-4 Streams Transmission Over 3G Networks

Computer EngineeringKyungpook National University 1

Joint Source-Channel Coding for Joint Source-Channel Coding for MPEG-4 Streams Transmission Over MPEG-4 Streams Transmission Over

3G Networks3G Networks

Fang Zhijun, Xu Shenghua, Wan ChangxuanWu Shiqian, Wang Zhengyou, Zeng Weiming

Wireless Communications, Networking and Mobile Computing, 2005.

Lee, Ick-Soo

2Computer EngineeringKyungpook National University

ContentsContentsIntroductionSystem ArchitectureJoint Source-Channel Coding Scheme

TCP and UDP Protocol3GPP/3GPP2 Turbo Codes

Turbo CoderTurbo Decoder

Data Partitioning and UEPSimulation & ResultConclusion


AbstractAbstractThe critical important MPEG-4 streams such as the BIFS (Binary Format for Scenes), OD (Object Descriptors) and IOD (Initial Object Descriptors) streams are transmitted by using TCP (Transmission Control Protocol)MPEG-4 audio/video ES (Elementary Streams) are transmitted by using UDP (User Datagram Protocol) over 3G channels. Transmission UDP packets is adopted UEP (Unequal Error Protection) Turbo codes according to MPEG-4 audio/video data partitioning.Only video ES have been discussed.


IntroductionIntroduction3rd Generation Partnership Project (3GPP) & 3GPP2

New worldwide standards for the creationDeliveryPlayback of multimedia over newHigh-speed wireless networks

The aim of the 3rd generation networksCombine the multimedia services of the Internet and provide multimedia services over wireless mobile platforms.


IntroductionIntroductionThe stability, interoperability and robustness offered by MPEG-4 make it an ideal solution for mobile networks and it has been selected by 3GPP and 3GPP2 for applying on 3G phones.Some of MPEG-4 new techniques suitable for wireless such as scalable and error-resilient video coding techniquesMPEG-4 system streams have not consideredThis paper present a new joint source-channel coding (JSCC) scheme of transmitting MPEG-4 streams over 3G systems.


System ArchitectureSystem Architecture3G phones system can be divided as three layers, namely physical layer, link layer and upper layer.


System ArchitectureSystem ArchitecturePhysical layer

Provides data transfer service to higher layers. Main purpose is to convert data bit stream into a format suitable to traverse the media.

Link layerComposed of media access control (MAC) and link access control (LAC) sub-layers.MAC sub-layer administers and controls the material of physical layer according to the requests of different service objects from LAC, and provides levels of quality of service (QoS) for them.LAC is in charge of providing higher level QoS control over MAC, which is to meet the requests from objects above, normally realized through the method of ARQ.


System ArchitectureSystem ArchitectureUpper Layer

Integrates the functions of network, transport, session, presentation and application layers in open system interconnect (OSI) reference model. Deals with the signaling for multiple services, the control and processing on voice service (circuit and package types) and data service (IP service, data in circuit or package, short message service).

CDMA2000 uses correlation code or Turbo code in channel encodeConnection-oriented TCP transfer mode is used for critical system streams such as BIFS, OD and IOD streams, while UDP is applied for MEPG-4 video streams.


Joint Source-Cannel Coding Joint Source-Cannel Coding SchemeScheme

TCP and UDP ProtocolMPEG-4 streams have to be converted into packets for transport over the wireless network, TCP and UDP are the basic transport protocols for media streaming.Multiplexing, error control, and flow controlThe main objective of transmitting video over mobile networks is to provide interactive and conversational services.The MPEG-4 critical important streams, such as BIFS, OD and IOD, are transmitted by using TCP.This implies that all the video services offered over 3G for instance must run in real time with one-way delay not exceeding 200 ms per service. In order to meet these delay requirements, it is not possible to use retransmissions or ARQ


Joint Source-Cannel Coding SchemeJoint Source-Cannel Coding SchemeOn the end-to-end level, UDP is typically employed as the transport protocol for the MPEG-4 video ES. However, since the UDP does not guarantee packet delivery, a UEP Turbo codes has applied to provide the error protection in this work.


3GPP/3GPP2 Turbo Codes3GPP/3GPP2 Turbo CodesTurbo Codes

Gaining increasing acceptance as the viable commercial FEC code for broadband wireless applications.Performs well under the high noise environmentGood anti-fading, anti-jamming3G standards and digital video broadcast (DVB) adopted Turbo codes as one of their error correction schemes.


Turbo CodesTurbo CodesParallel concatenated by two or more feedback systematic convolutional encoders through a random interleaver.


Turbo DecoderTurbo DecoderBecause Turbo code is encoded by interleaving two or more component codes of the same information sequences, its decoder is usually composed of two or more component coding units and deinterleaver.


Turbo DecoderTurbo DecoderDerived from convolution code decoder, Turbo decoder use soft decision

With binary phase shift keying (BPSK, m = 1) or quadrature phase shift keying (QPSK, m = 2) modulation the decoder constant C should be adjusted

A: the signal amplitude σ2: the normalized noise variance


Turbo DecoderTurbo Decoderσ2: the normalized noise variance

Eb / N0 : the ratio of energy per bit to single sided noise densityFor fading channels, the values of A and σ 2 should be averaged across the block to determine the average value of C


Data Partitioning and UEPData Partitioning and UEPThe importance of the data in different parts of the video streams is not same.Motion Maker is decoded correctly yet texture-coding DCT is wrong, MV is used and DCT is dropped


Data Partitioning and UEPData Partitioning and UEPTransported using connectionless-oriented UDP

coded at high bit rate as unimportant information.Transported using connection-oriented TCP

consider the MB header, MV and shape coding information as important data

coded with low bit rate Turbo codes.important data in MPEG-4 streams such as BIFS, OD, and IOD


Simulation & ResultSimulation & ResultSix times iterative 1/3 low bit rate Turbo code is adopted for the important information in the MEPG-4 stream, while four times iterative 1/2 high bit rate Turbo code is used for the parts with less importance.


Simulation & ResultSimulation & ResultThe comparison of the error probability between no error protection (NEP) and Turbo error resilient coded situations under various Eb / N0 .


Simulation & ResultSimulation & ResultThe PNSR of the images under various Eb / N0 for the first 100 frames of the sequence.


The comparison of average PSNR under various Eb / N0

and different error protection for the first 100 frames.

Simulation & ResultSimulation & Result


ConclusionConclusionA novel joint source-channel coding technique that provides robustness to error from fading channel has been described in this paper.MPEG-4 streams, the BIFS, OD, and IOD are critical important streams. Therefore, these key streams have been transmitted by using TCP. The audio/video ESs are transmitted by UDP over 3G channels, then according to MPEG-4 data partitioning, we transport the UDP packets by using UEP turbo codes.Simulation results show that low bit error rates can be obtained effectively over the 3G wireless channels by using our provided method.

Joint Source-Channel Coding for MPEG-4 Streams Transmission Over 3G Networks

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