Improving Performance Of Video Playback On Godson2 By System Optimization

Video playback is one of the most important applications on Godson2 CPU. It's very important to improve the performance of video playback on Godson2.The total time of video playback consists of 4 parts: video decoding, video output, audio decoding/output, and system overhead. Video output occupies a considerable part of the total time. Godson2 implemented"Uncached Accelerating"technology, which can accelerate display memory access and decrease the time of video output greatly. But Linux, which is the major OS on Godson2, doesn't support this technology yet. A high performance video output library called"Vidix"in Mplayer, which is the major software for video playback on Linux, can also decrease the time of video output greatly. But it can't run on Godson2 yet.This thesis analyzed the procedure of video output in Mplayer, improved the performance of video playback on Godson2 by system optimization (including supporting"Uncached Accelerating"in Linux and porting Vidix on Godson2). Results show that the time of video output is reduced by about 71% and the total time is reduced by about 20% when playing MPEG-1 video as fast as possible without sound; and the display bandwidth is increased by 2 times to 3 times in most cases.