用于无线多跳网络视频流传输的优先级机会网络编码  

Prioritized Opportunistic Network Coding for Video Streaming over Wireless Multi-Hop Networks

作　　者：崔华力[1] 钱德沛[1,2] 张兴军[1] 伍卫国[1] 

机构地区：[1]西安交通大学电子与信息工程学院,西安710049 [2]北京航空航天大学中德软件技术联合研究所,北京100191

出　　处：《西安交通大学学报》2013年第12期13-18,共6页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(60673180);国家科技支撑计划资助项目(2011BAH04B03);国家高技术研究发展计划资助项目(2011AA01A204;2012AA01A306)

摘　　要：针对多视频流共享传输链路时存在的编码数据包不匹配问题,提出一种用于无线多跳网络视频流传输的优先级机会网络编码方法。该方法对各传输流中优先等级不同的数据包执行不同的编码操作,在源端对视频流分段进行流内编码,并通过添加冗余增强传输可靠性;在网络中间节点,对优先等级高的数据包进行流内冗余编码,对次优先等级数据包按队列次序与另一视频流进行流间编码,对剩余数据包则直接传输或选择性丢弃。该方法能尽力保证视频流基本层数据被接收,同时一定程度上减少了发送次数,充分利用有限网络带宽资源。实验结果表明,所提方法能够有效地提升视频传输质量,较之已有的机会网络编码方法,接收端视频质量平均值提高了2dB以上。Abstract： A prioritized opportunistic network coding scheme is proposed to solve the mismatch problem of coding opportunities between multiple streams. Packets with different priorities are treated differently. The generation-based intra-session coding with redundancy is performed at the source nodes to increase transmission reliability. At the intermediate nodes, the packets with highest priority are re-encoded with redundancy data within the generation, those with lower priority are performed XOR operation with the packets of another stream, and the remaining packets are forwarded directly or discarded selectively. This strategy ensures that the base layer packets of the streaming are received by the destination node with high probability and that the number of sending packets is reduced while taking full advantage of the limited network bandwidth. Experimental results show that the proposed scheme enhances the video quality effectively, and improves the average peak SNR by more than 2 dB in a comparison with the existing opportunistic coding scheme.

关 键 词：网络编码 视频流传输 不等差错保护 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]