| Nowadays, video is one of the most important communication mode. Due to the large amount of video data, video should be compressed to get rid of its redundancy before transmission or storage. H.264/AVC proposed in May 2003 has very good performance in compression rate and network compatibility, and is widely used in various applications. With the increasing of video frame rate and resolution, more efficient compression algorithm is required, which promotes the generation of new video compression recommendation, H.265/HEVC can realize higher compression ratio, meanwhile the complexity of the algorithm increases several times. So the research of H.265/HEVC algorithm and its efficient implementation on embedded platform means a lot.After the introduction of the basic conceptions and background of video compression, the basic principles of video compression and some core technologies are analyzed in this thesis, such as coding block partition, prediction technique, entropy coding and parallel processing mechanism. And the new characteristics of H.265 are compared with H.264. Open source code x265 based on VS2010 is selected as the prototype for the simulation of the encoder. The encoder is built and the influence of important encoder options on video quality and coding efficiency are evaluated then. Finally, the encoder is modified and transplanted onto TMS320C6678 platform, and the actual test is performed then.H.265 includes a series of new technologies, such as larger macro block, more flexible macroblock partition and more accurate prediction. According to the simulation results,to obtain the same compressing quality, the bit rate of x265 can be reduced by 40% compared with the x264’s, while the encoding complexity increases dozens of times. By transplanting the algorithm to DSP platform, the encoding speed is improved effectively, the real-time performance of the system is enhanced. |
