The Research And Optimization Of Intra-prediction Algorithm In H.264

H.264/AVC is the newest international video coding standards.It was developed by Joint Video Team(JVT) consisting of experts from ITU-T's Video Coding Experts Group(VCEG) and ISO/IEC'Moving Picture Experts Group(MPEG). To achieve a better compression performance, H.264 brings up many new ideas,such as spartial prediction in intra-coding,alterable block size motion compensation,4×4 integer transformation, and content adaptive binary arithmetic coding(CABAC), etc. Compared to MPEG-2,H.264 increased by 50% in coding efficiency. But the performance improvement is at the expense of computational complexity increase. H.264 main profile decoder requires 3 times computing capability than H.263, and 10 times than MPEG-4 simple profile, The augment of computation complexity constrains its application in real-time system.In Chapter 1, it introduced the basic theories of video coding.In Chapter 2, it introduced existing standards of video coding,the background of home and abroad, described their technology characters and at last pointed out H.264'advantages.In Chapter 3, it simply introduced the structure of encoder and decoder of key technologies and main performance of H.264 standard, especisally emphasized in the key technologies in video coding layer of H.264.In Chapter 4, it analyzed the intra-prediction method in detail, and researched deeply the computationally complex part-prediction mode selection, then proposed a fast mode selection method. The fast method changed the order of mode selection, 16×16 encoding modes was preferentially considered than 4×4 encoding modes, and utilized the correlation of prediction modes between neighbor blocks. By means of threshold comparison, to decide whether the current block choose its neighborhood's prediction mode as its own prediction mode. The simulation results showed that the fast mode selection method shortened coding time and improved the coding efficiency with a little decrease for PSNR and coding bits rate. In chapter 5, it introduced PFGA , then realized some function blocks of H.264. A brief summary and prospect was given in the last chapter.