Research On Implementation Of Real Time Video Coding Using DSP On Low Bit Rate Channel

Video coding realization in narrow band channel is a hotspot in video processing field. Among many methods that realize video coding, the method based on DSP chip also bears remarkable advantage besides pure software method which used widely.The essence of video coding is digital signal processing, and DSP chip is more suitable for digital signal processing than general CPU. Thus, there will be of great benefit employ DSP chip video coding. In this paper the principle of video coding, the recommendation H.263 and the real-time signal processing system based on DSP chip are introduced first. A H.263 real-time video coding system based on DSP chip is then designed which follows the develop flow of a DSP system. The Bt819A of brooktree corp is selected for front-end video A/D transforming, Bt852 as video D/A, and the TMS320C6711 of TI corp. selected for H.263 core algorithm processing in the system hardware design. In the system software design, H.263 core algorithm modules (DCT, DCT, motion estimation) are discussed. Exploits the fact that many residual blocks become all zero blocks after DCT and quantizationin very low bit rate videocoding. A motion search algorithm asing zero block detection technology, is proposed in this paper.