H.264 Encoder Optimization Based On TMS320DM642

With the development of computer technology and multimedia technology,the range of video application grows wider and wider.Bacause of the high compression ratio and Good ability of network error correction,H.264 coding standard released by JVT(Joint Video Team) becomes the major video coding standard of real-time video communicationS,video on demand,digital television broadcasting,digital video Ssurveillance and other fields.On the other hand, with the rapid development of DSP technology, embedded video equipments have been widely used because of their flexible, convenient, mobile and other features.The development of video encoder and related product based on embedded platform is an important work in the areas of video application.The main achievements of this paper are focused on the optimization of H.264 encoder based on DM642 platform.This paper analyzes the inter prediction algorithm and intra prediction algorithm which have the highest degree of computational complexity in H.264 encoder,and improve this two algorithms based on existing algorithms.The new algorithms add an pre-judgment method in mode selection part of prediction algorithms.In this way,the encoder can reduce the number of prediction mode identification and motion estimation,improving encoding speed with a very small loss in image quality.This paper has done the C code optimization and assembly optimization base on the structural characteristics of DM642. C code optimization means combined compilation options,inline functions, data packaging, software pipelining and other methods to optimize the encoder.Assembly optimization means using assembly language rewritting the small modules that have characteristics of high computational complexity, frequently called and independent in the whole framework of the encoder system,in this way,these modules have achieved greatly enhancement of the running efficiency.