异构无线网络下实时视频传输码率控制策略

Rate control strategy for real-time video transmission in heterogeneous wireless networks

针对异构无线网络下实时视频的自适应码率控制问题,提出一种基于帧类型的实时视频码率控制方法。基于多路并行传输缓冲状态获得在低时延约束下的视频帧比特数上界;建立以视频质量提升为目标,端到端传输时延为约束的帧级别码率优化问题;基于获得的视频帧比特数上界和所建优化问题模型,分别针对I帧和P帧设计不同的帧级码率控制策略(frame-level rate control strategy,FRCS)。实际测试平台验证结果表明,所提算法在低时延传输要求下可以有效提升视频质量,当时延约束为250ms时,帧超时丢失率低于3%。

Aiming at the adaptive rate control problem of real-time videos in heterogeneous wireless networks,a real-time video rate control method based on frame type was proposed.The upper bound of the video frame bits under low delay constraint was obtained based on the concurrent multipath transmission buffer status.A frame-level rate optimization problem with end-to-end delay constraint and the objective of improving video quality was established.On the basis of the obtained upper bound of frame bits and the optimized problem model,a frame-level rate control strategy(FRCS)for I-frame and P-frame was designed.The real-world testbed verification results show that the proposed algorithm can effectively improve the video quality under low-latency requirement.When the delay constraint is 250 ms,the frame overdue loss rate is less than 3%.