基于HTTP的视频流网络传输

Network delivery over HTTP for video streaming

近年来,基于HTTP(Hyper Text Transport Protocol)的网络视频流传输方式越来越受到人们的关注,同时出现了若干相近的解决方案,实现了在HTTP上的动态自适应视频流传输。MPEG和3GPP在这些方案的基础上制定了一个新的基于HTTP的网络动态自适应流传输标准——DASH,并成为ISO/IEC国际标准于2012年正式发布。DASH系统工作于普通的Web服务器/客户端方式,它将同一内容的多个不同质量的视频流分片、定位和描述,使得这些视频分片能够如同普通文件一样通过HTTP协议在网络中传输。用户可以向服务器请求所需的视频,动态自适应地根据自己的网络带宽、接受能力进行选择、接收、解码和播放。DASH为视频流传输提供了一种高效、便捷的传送方式,特别适用于视频直播、点播、多屏显示等业务。随着DASH标准的逐渐完善,基于HTTP的网络视频流传输必将具有更加广泛的应用前景。

In recent years, the form of video streaming network delivery over HTTP attracts people＇s atten- tion, and a number of similar delivery solutions for implementing dynamic adaptive video streaming over HTTP are available. Based on these solutions, MPEG and 3GPP have developed a new standard-DASH for network dynamic adaptive streaming delivery, it was published as an ISO/IEC international standard in 2012. The DASH system works in classical Web Server/Client form, segments, locates and descripts video streaming in various qualities, such that the video fragments can be sent as a general text files using HTTP protocol over network. Client users can dynamically and adaptively select, decode and display their required video according to their network band width and receiver abilities. DASH has provided a high efficient and popular approach for network video streaming delivery, and can be used in many situa- tions, for example live video sending, video on demand, display on various screen, etc. It is believed that with the development of DASH standard, the technology of network video streaming delivery over HTTP will be more widely application prospect.