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In order to save the transmission bandwidth, storage space, video codec technology has already become one of the focuses of the research and industrial applications. AVS audio and video codec standard of independent research and development, is one of the criteria of the current state-of-the-art audio and video compression codec. Compared with other popular international standard, it has a high-performance, calculation of low complexity, low patent licensing fees. The AVS standard group has released the Enterprise Edition Reference Software, the encoder part-time but the efficiency is very low, is not conducive to practical application. Therefore, from the point of view of practical application, the first entire encoder optimized, including restructuring, code optimization and optimization of core modules to achieve, then consuming serious mode selection module, AVS itself algorithm, and significantly improve the speed of the encoder coding. First, the article briefly describes the video coding standard, popular at home and abroad, the AVS standard H.264/AVC done, and gave details of AVS video standard coding framework and coding process, and intra / inter prediction key technologies, sub-pixel interpolation, integer transform and quantization loop filter, entropy coding. Second, we the the encoder reference model rm52j Working Group overall optimization, optimization, including the structural adjustment of the encoder, code optimization, as well as the key technology module optimized achieve. Which makes the encoder encoding process of structural adjustment clearer, code optimization module optimized achieve improved performance of the implementation of the program, to improve the encoding speed. The experiments show that, for a variety of characteristics of the video sequence, at different bit rates, after optimization of the encoder encoding the total time savings of 26% to 35%. Again for AVS rate distortion optimization mode selection consuming serious problem, according to the characteristics of the AVS encoding algorithm, combined with some classic fast algorithm proposed two new suitable AVS interframe macroblock fast mode selection algorithm. An algorithm using a skip macro block pre-decider, and texture information of the macro block itself, its advantages are encoding speed is improved significantly, especially for relatively fixed background in the video sequence, the speed increase to up to 60%, more suitable for video conferencing, etc. Background relatively fixed and real-time applications requiring high; another algorithm using macroblock and take optional 8 × 8 and intra mode prediction strategy, its advantages to all conditions of the judgment in the algorithm is completely based on the video sequence the characteristics of various sequences of motion and texture characteristics are able to ensure that under the premise of the coding performance significantly save coding time. Specific video applications, depending on demand, to select a suitable fast algorithm to use. Finally, through analysis of AVS intra prediction technology and existing mode selection algorithm proposed an effective low-complexity intra mode selection fast algorithm. The algorithm uses the correlation between the adjacent blocks optimum prediction mode and the intra-block change in brightness directivity pattern anticipation, to narrow the range of candidate patterns. The experimental results demonstrate, the present algorithm in the case of almost constant image quality and bit rate, coding the time savings of 17% -29%.
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