A Joint Source-Channel Coding Scheme Based On Unequal Error Protection Of H.264

In the wireless and mobile network environment, the demand of multimedia applications is growing. The coding efficiency of video signals is also increasing. Accompanied by many the introduction of new access technologies, wireless channel has had higher throughput, which makes the transmission of video signals in the radio channel is possible. However, wireless networks have time-varying, limited bandwidth, relatively higher bit error rate characteristic, therefore, video coding methods for wireless communication should not only have a high compression capability and should also have a good anti-error performance.The joint source and channel coding will cascade up source encoder and channel encoder and maintain the independence between the two encoders, but joint optimize of their encoded parameters. Through the rational allocation of the original multimedia data and the protection of data transmission between the bandwidth, to achieve the rational allocation of redundancy of the source and channel, thereby achieving optimal parameters of the joint source-channel coding system. Thus, on the one hand can reduce system complexity, on the other hand can achieve the purpose of the joint coding by assigning rate between the source and channel.The content this paper studies is, combined with the characteristics of H.264 video compression and wireless channels, uses the data segmentation schemes submitted by the H.264 standard and unequal error protection ideas, based on H.264 standard the paper firstly studies subject of video information segmentation, frame compression, inter-frame compression, and other basic principles, so as to achieve different importance, different bit rate source compressed streams, and using redundant multi-bit rate-compatible puncturing Turbo code as channel coding, to achieve the required rate of the different channel coding, unequal error protection for the channel, lay the foundation for the implementation. Finally, based on wireless channel parameters, combining the variable bit rate of H.264 video compression and multi-redundant puncture rate compatible Turbo code (RCPT code), and make a arithmetic of joint source channel coding system based on unequal error protection of video transmission adaptive resource allocation problems, and design a joint source and channel coding systems can change the rate adaptively according to the wireless channel. In the case of the channel bandwidth is limited, the system can make a reasonable rate distribution between the sources and channel so that the quality of the video decoder to resume in a variety of channel conditions have reached a relatively good results.