质量均衡的FGS率优化分配策略

Rate optimization for constant quality fine granularity scalable video streaming

为了保证在带宽约束信道下的视频传输能够获得最小的失真,同时降低接收端的视频失真波动,提出了一种精细粒度可扩展编码(FGS)率优化鲁棒传输策略.该策略首先根据网络可用带宽和丢包特性对FGS视频增强层进行率分配,然后根据FGS视频增强层之间存在的不同重要性,采用不均等前向冗余纠错(FEC)方法进行错误保护.在率分配和FEC非均等保护这两个步骤中,都考虑了网络丢包对视频质量波动的影响.试验结果表明,该方法能够有效减小接收端因丢包引起的视频质量失真,同时能大幅度降低视频质量的波动.

In order to minimize both the mean video quality degradation and the inter-frame quality fluctuation when transmission over the bandwidth-limited packet-loss channel, a robust fine granularity scalable （FGS） video transmission scheme was proposed, which aims to reducing the average single-frame distortion and inter-frame quality fluctuation at the same time. Firstly channel budget and packet-loss property were used to determine the bits of enhancement layers that should be allocated for each frame. Then unequal loss protection （ULP） using forward error correction （FEC） was applied to different FGS enhancement layers based on their significance. Inter-frame quality fluctuation due to packet-loss was considered while optimizing FGS bits allocation and unequal loss protection. The simulation shows that the proposed method can effectively reduce the inter-frame quality fluctuation while maintaining a good average single-frame quality.