The Design And Optimization Of AVS-M Decoder Based On PXA255 Embedded Platform

AVS-M is a new generation of advanced image compression coding standard for mobile video and it is China's own audio and video coding technology developed as the seventh part of the AVS standard.It is developped for the requirtment of the moving image compression technology in the mobile conmunication field of the digital storage media, network streaming, multimedia communications and so on.It has high compression, high quality and relatively low hardware complexity.With the third generation mobile communication technology development amd implementation it become a focus to research the AVS-M decoder in the field of the packet-based network multimedia services, video telephony, remote video monitoring which based on the embedded technology.This paper presents the AVS-M decoder design and optimization based on the PXA255 platform.With the in-depth research on the embedded systems and digital image processing technology, AVS-M video decoder design is proposed based on PXA255.Using the Intel XScal series PXA255 ARM processor development board as the Hardware platform and embedded Linux as the software platform. According to the hardware platform and AVS standard,the thesis built the AVS-M video decoder framework and development environment,for example,building the cross compiler development environment based on the embedded systems,analysing the Bootloader start process,the Bootloader transplantation,ARM-Linux kernel configuration and migration for PXA255 target board. AVS-M video decoder software design include: according to the decoding process design AVS-M decoder framework and decoding algorithm.Divide the decoding function modules and design them,do the C-Ievel code optimization; improve the algorithm flow of the pixel interpolation module, do the assembly-level code optimization.Cross-compile and transpalte the Mplayer and add the decoder into the MPlayer decoding library. Play AVS video sequences,build the test platform and test it according to the AVS standard.The test results show that on the PXA255 ARM processor, decoder conformance to the requirements of AVS standard,and the decoding rate up to 24.57f/s or more, which basically reach the requirements of streaming real-time transmission. The decoder's design process is simple and development period is short.The decoder can be used in the interactive storage media, broadband video services, multimedia mail, video conferencing terminals, control terminals and so on.