Research On Audio-Video Coding/Decoding Technology Based On DSP

Video-audio coding/decoding realization of low bitrate communication is important aspect in multimedia information processing. Among many methods, which realize video coding and audio coding, the method based on DSP appears remarkable adventage, such as high spead, easy to modify and esay to migrate, because DSP's core is designed to processing digital signal and is more suitable for signal processing than general CPU. Audio-video coding/decoding theory is introduced firstly in this paper, then a video system based on DSP is designed, the method of debugging this system is presented in detail, the realization of H.263 recommendation and G.723.1 recommendation based on DSP is introduced finally. The TMS320C6711 signal processor is adopted in video system as main processor, and BT819A is adopted as video A/D collection chip. Firstly the core algorithms of two Recommends are simulated on PC, then migrated to TMS320C6711 DSK. H.263 core algorithm modules (DCT, DCT, motion estimation) are discussed, A motion search algorithm using zero block detection technology, is proposed in this paper. We optimized G723.1 Recommend based on DSP architecture. Good effect has been gained by optimizing the two core algorithm modules based on the configuration of DSP and implementation of code.