无线视频传输容错算法研究新进展

Review of error resilience techniques for wireless video transmission

视频信号经过压缩编码后通过Rayleigh衰减无线信道传输,容易受到突发性错误的影响,造成视频传输质量下降。容错(error resilience)是保证无线视频传输质量的重要措施。本文首先对几种无线信道模型进行了概括与比较,然后总结了各种容错算法的优缺点和最新研究进展情况。重点讨论了在传输层实施的前向纠错编码(FEC)和反馈差错控制,在编码器端根据不同的信道传输特性所采用的容错算法,包括帧内刷新、长期限存储、分层编码和多描述编码。本文还通过一种传输方案对容错策略的组合实施情况进行了分析。最后探讨了无线视频传输容错算法的发展趋势和挑战,提出了几个值得重视的发展方向。

Compressed video bit-stream transmitted over Rayleigh fading wireless channel is prone to be impaired by burst errors, which result in video quality degradation. Error resilience techniques are the important measures that ensure video transmission quality. In this paper, we first introduce several wireless channel models. The advantages and disadvantages of different error resilient techniques as well as their recent development are discussed. The emphasis is on error resilient techniques on transport-layer such as forward error correction coding, feedback-based error control and error resilient tools on the encoder end including Intra fresh, long-term memory prediction, layered coding and multiple description coding. The performance of combined error resilient techniques is also introduced. We show the challenges and future works of error resilient techniques in the last part.