.h.264/avc Video Coding Algorithm And Its Dsp Implementation

New generation video compression standard H.264/AVC, which is suitable for low bit rate transmission, is developed strongly now. It has higher compression ratio and better adaptability for IP and wireless network, which make it used widely in fields of digital video communication and storage. In addition, DSP technology, which develops so quickly recently, could provide a platform for the complicated new generation video coding system. Consequently, research on H.264/AVC video coding algorithms and its realization with DSP has become a hot and difficult subject in video communication industry.The key technology of H.264/AVC was studied systematically in this paper, and the main achievements of work were listed as follows:Research achievements on Algorithms: Rate distortion optimized strategy, intra prediction, variable-sized block inter prediction mode decision, integer core transformation and quantization, and code encapsulation were studied deeply by the reference JM code in this paper. According to the analysis on old methods, a mixed features-based fast intra prediction mode decision method for H.264/AVC was proposed. In this method modes were filtered by mixed features in advance, and the decision approach was speeded up. The experiment results showed that the new scheme was able to achieve a reduction of up to 50% time for intra encoding, with similar encoding performance to the original RDO full research method in H.264/AVC reference software. Furthermore, a fast inter block mode decision method for H.264/AVC was proposed in this paper. With the initial block size 8×8, all the block size modes were filtered by certain merging and splitting standards, which were constructed at the beginning. The experiments results showed that, compared with the original full research method, this fast method could reduce inter encoding time by 70% with little influence on encoding performance.Research achievements on DSP realization: The explore principle of DSP TMS320DM642 EVM and the optimization means for DSP code were studied. A video display GUI was made by use of DrawDib video functions in VC++, and the communication between PC and DSP were realized through PCI API functions. H.264/AVC I frame encoder of basic profile was realized in CCS, and it was emulated on DM642 EVM. Effective optimized methods of data type, memory, C code, and assembler were proposed for DSP code of the encoder, and by them the encoding speed could be accelerated to more than 4 times compared with original code. Then the code documents were decoded by the decoder on PC, and the test data showed that the performance accorded with H.264 /AVC standard well.