2002年中国开始制定了新一代数字音视频编解码标准———AVS。由于它采纳了近几年来国内研究的先进音视频编码技术,其不仅与H.264/AVS相比,具有较低的复杂度,并可通过一站式授权方式支付少量费用来获得AVS使用权,因此可作为中国卫星电视直接入户方案的一种较好,且具有竞争力的候选标准。在对AVS和MPEG-2的差异进行比较的基础上,分析了两种在传输系统中替代MPEG-2的方法:直接AVS编码和AVS转码,并给出了一种转码方案,最终实现了新一代基于AVS卫星视频广播系统。

AVS(audio video coding standard) is a digital audio-video coding/decoding standard proposed by China since 2002.It adopted many digital audio-video codec techniques developed by Chinese companies and universities in recent years.It has lower complexity in comparison with H.264/AVC.And very low royalty fee will be charged through one-step license to use AVS including all tools.So AVS is regard as a good and competitive candidate for Chinese satellite TV signal directly to home(DTH).In this paper,the difference of AVS and MPEG-2 is studied.We also analyze alternative approaches,such as direct AVS codec and AVS transcoder,to transmit video stream via satellite,and discuss the design of corresponding transcoding scheme.At last a realization of new generation satellite system with AVS is presented.