Research On AVS Video Decoding And Realization/Optimization Based On C64

With the development of multimedia technology,it has entered a digital information explosion time of increasing demand for audio and video,then come to the equipment of huge storage space and transmission efficiency.Therefore,how to compress greatly the data of video has became a hot spot of researches.The current popular of video compression standard were MPEG and H.264,which is published just before China Standard AVS(Audio Video coding Standard) was issued in February 2006.The AVS with an independent intellectual property right has owned by China.AVS had abstracted the advantages of MPEG and H.264,and found an equilibrium point of compression rate and the feasibility.AVS now has become an international standard of the IPTV video coding and has a broad market prospects.Video coding part of AVS has high compressibility and low complexity so that it can be widely used in many fields,for example,digital television and network video.It can be implemented very conveniently on the DSP and get a high efficiency in DSP.However,to satisfy a real-time require,the optimization of codec was required in DSP.This thesis was organized into three parts:Part 1.The current popular standard of video coding and the AVS coding process are briefly introduced.And then,according to AVS test decode program with the open-source code, which is published by National Source Coding Center Corporation,a AVS stream decode flow from sequence to block was given layer by layer.Part 2.The performance bottleneck of AVS test decode software is analyzed by Intel(?) Vtune^TM Performance Analyzer on PC and some main time-consuming modules are optimized. In this section,we put forward a new interpolation search algorithm,a new block-reconstruction method,a new frame-level decoding scheme and a new deblock loop filter flow,respectively. Based on our research results,the whole decode speed up to 46.768FPS after the project-level optimization.It shows that the real-time objective was arrived,the transplant and optimization foundation of C64 platform was be build.Part 3.Based on the optimized code by PC,the transplantation and more optimization of AVS test decode program has completed on TMS320C64x platform.Using the compiler intrinsic of C64 instruction set,the project-level optimization,4-bytes data read module optimization, Exp-Golomb decoding module optimization and rgb2yuv module optimization was be put forward respectively.The final optimizes result of I,P,B frame respective average decoding times was 24ms,64ms and 67ms,respectively.AVS 720×576 standard resolution video quasi-real-time C64 platform decoding was basically completed using the optimization mouthed provided in this thesis,the optimization scheme has some practical value.