对具有帧间相关性的分层视频码流的非均匀错误保护

在分层视频码流的网络实时传输中，非均匀错误保护（UEP）技术已经被广泛地研究。至今为止，几乎所有的UEP相关工作都是针对具有链式结构的单一码流。但是，在一些实际的图像及视频编码系统（例如MPEG-4）产生的码流中，都存在着更为复杂的树型相关性结构。针对这种具有树型相关性结构的码流提出了一种打包方案，并在此基础上提供了两种带宽分配方案。试验中，采用MPEG-4FGS作为信源编码器。试验结果表明，采用灵活的帧间自适应带宽分配方案可以有效地提高系统性能。

UNEQUAL ERROR PROTECTION FOR SCALABLE VIDEO WITH INTER-FRAMEDEPENDENCIES

Unequal error protection(UEP) for transmitting scalable image and video bitstreams over packet erasure networks has been extensively studied.Most of the existing works consider UEP for a single source bitstream with chain-structure dependencies.However,in some state-of-the-art image and video coding techniques,such as MPEG-4 fine-grained scalable(FGS),there exists more complex tree-structure dependencies.In this paper,we propose a packetization framework for tree-structured bitstream,and present two rate allocation algorithms.(Using) MPEG-4 FGS as the source encoder,our experimental results show that the performance in terms of mean PSNR can be improved by(adaptively) allocating available bandwidth to different frames.