Research And Implementation Of X264 Encoder Based On DM642 DSP

As a video coding standard for next-generation multimedia, H.264/AVC adopts a number of advanced technologies differs from the previous standards. In addition to improve coding efficiency and coding performance, it also has some enhanced capabilities, including error resilience and flexibility for effective use over a broad variety of network types. H.264/AVC provides a technical solution for a broad range of applications, including broadcast television, video storage and playback, video conferencing, etc.The paper introduces how to develop and optimize the H.264 "baseline" encoder ported from VC platform on the hardware platform based on TMS320DM642. The source program is the encoder part of the "x264" which is one of the open H.264 codec software. For the implementation of H.264 video encoder based on DSP, we should consider the character of DSP, except the characters of video encoding algorithm.This paper affirms the basic search methods as diamond search through some research of the integrate pixels searching. Considering the feature of the structure and instruction of DM642, in addition to use EDMA for loading data between different memories to make the data transfer work more efficient, we also propose the optimization strategy of two level Cache; Furthermore, some optimization and modification of the software water flow is needed in the project, and changing C code into compiled code in order to make the orginial code more suitable for DM642.Based on thsese strategies and the experimental data, optimized x264 encoder ported on DM642 platform can encode 20-35 fps for cif resolution video. The decoded video pictures provide high subjective and objective quality.