地铁车载高清视频播放系统的优化

Optimization design of high-definition video player system for subway

针对目前地铁视频播放系统普遍存在的视频处理终端死机、图像清晰度低、播放不流畅等问题,设计了一种以全志A20芯片为核心处理器、搭载Linux操作系统、以UDP为网络传输协议、支持720 P和1 080 P视频分辨率的高清视频播放系统,并针对地铁车载环境,改进了UDP并优化了H.264视频编码算法.实验结果表明:算法优化后的编码时间平均缩短了50%,解码后视频与原视频的相似度高达0.979 3;在较差的网络环境下,采用改进的UDP,数据丢包率平均下降了62.33%.在系统运行过程中,客户端显示画面清晰、流畅,满足了地铁车载环境下的高清视频播放要求,具有广阔的应用前景.

Video player systems used in subway usually have the problems such as crash of video processing terminal,low image resolution and intermittent video play.Here,a high-definition video player system was designed based on an A20 chip equipped with Linux operating system.The video player system uses UDP as the network transmission protocol and supports 720 P and 1 080 P video resolution.The UDP has been improved and the H.264 video coding algorithm has been optimized according to the subway environment.As a result,the coding time of the optimized algorithm is reduced by an average of 50%,the decoded video has a similarity to the original video as high as 0.979 3.Besides,using our improved UDP,the data packet loss rate drops by an average of 62.33%in the poor network environment,leading to a clear and smooth video play in the terminal.These results demonstrate that the system meets the requirements of high-definition video play in the subway environment,and thus has broad application prospects.