一种针对无线视频传输的帧内宏块更新方法

摘要

帧内宏块更新是视频传输中一种重要的错误恢复方法.针对无线视频传输中的错误恢复问题进行分析,并对几种不同的帧内宏块更新方法进行对比,提出一种改进的帧内宏块更新方法.通过分析视频中主要的运动方向,选用不同的帧内宏块更新策略,在保证错误恢复能力的同时,尽量减小帧内宏块在码流中所占的比例.分别采用MPEG-4的AIR方法、随机更新方法、按列更新方法和所提方法对不同的测试序列进行了错误恢复能力的实验.结果表明,所提方法既能保持良好的错误恢复能力,又能降低码率的波动以满足编码与传输实时性的要求,具有良好的主客观效果,同时与现有的各种视频编码标准兼容.%Intra macro block refreshing is an important error resilient approach for video transmission. The error resilient of wireless video transmission was analyzed and several intra macro block refresh methods were compared. After that,an improved macro block refresh approach was proposed. Based on the analysis of the mainly motion direction of the video, the approach chose different intra macro block refresh strategy to decrease the proportion of intra macro block in the frame and maintained the similar error resilient ability. The proposed approach was compared with number of intra macro block refresh methods for the same video frame loss pattern. The experimental results show that the new approach can refresh the decayed video quickly, at the same time increase the coding efficiency. The proposed approach has a good subject and object quality and compatible with all the current video coding standards.