The Design And Optimization Of H.264 Video Encoder Based On DM643

H.264/AVC as the the latest video encoding standards,which has been studied deeply in academia and engineering fields and begins to practical application,jointly developed by the ITU-T VCEG and ISO/IEC MPEG.Comparing with the previous video coding standards,H.264 has incomparable advantages on compression rate, image quality,robust transmission,but superior performance is at the heavy price of complexity.When the standards was introduced,it is difficult to apply into actual projects,but with the deep study and the attraction of huge potential market,design a real-time video encoder has became the competing goal for the major manufacturers and research institutes recently.Focuse on the theme of design,migration and optimization a real-time H.264 video encoder,this paper worked from the establishment of MATLAB simulation model to new rapid improvements algorithms,and then to the transplant and optimize the whole process based on VC++ and DM643 platform.In the motion estimation module,because most fast algorithms easily lead to local minimum or the wrong search direction,a new block-matching algorithm based on muti-octagon-grid was put forward in the paper and the search speed was improved by 42.4%;In the intra-prediction module,this paper made a pre-detection by using the sobel algorithm to pick out the redundant candidates and the intra-predict speed was improved by 61%. In the inter-prediction module,the paper took various measures in advance based on CBPand MVD as well as early SKIP mode decision and the inter-predict speed raised 53%.Based on the realization of basic level design requirements,this paper completed cutting,grafting and optimizing of H.264 video algorithm under the VC++ and achieved the performance CIF 44fps.Finally,the article completed code-level, system-level and instruction-level optimization on TI DM643 platform and achieved the performance CIF 20fps.To achieve the considerable image quality as the origin's,this article seeks to reduce the complexity and improve the speed as much as possible.The improved algorithm proposed in paper provides a theoretical support and the design,migration and optimization based on VC++ and TI DM643 will provide a reference design for the real-time H.264 encoder and has important theoretical and practical significance for the development of practical products.