数字电视传输流循环播放码流预处理的研究与实现

Realization of Pretreatment for DTV TS Transported in Cycle

数字电视传输流在循环播放时需要实时更新节目时钟基准、音视频解码时间标签和显示时间标签,接收机(机顶盒)才能正确解码．为此,提出并实现了通过对数据流进行预处理生成报告文件,循环播放时再按报告文件实时更新定时参数的算法．解决了多个传输流文件之间以及单个传输流文件循环播放时头尾的无缝粘接．使机顶盒接收、解码、系统时基、声音、图像以及声音与图像之间均能良好同步．

When the digital television transport stream（ DTV TS） is transported in cycle, it is necessary to renew the program clock reference, decoding time stamp and presentation time stamp of audio and video in time in order that the set top box （STB） can decode correctly. This paper suggests an algorithm that generates report file by dealing with the TS in advance, and then renews the related parameters according to the report file when the DTV TS is transported in cycle. This algorithm solves the problem of how to realize the seamless bonding of several TS files or one loop-played TS file. STB can receive TS and decode with proper synchronization, which can also be obtained in system time reference, audio, video, and between audio and video.