Adaptive Video Streaming With Optimized Bitstream Extraction and PID-Based Quality Control
Adaptive Video Streaming With Optimized Bitstream Extraction and PID-Based Quality Control
复制标题
具有优化比特流提取和基于 PID 的质量控制的自适应视频流
DOI：
10.1109/tmm.2016.2535270
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发表时间：
2016-06-01
影响因子：
7.3
通讯作者：
Guo, Zongming
中科院分区：
文献类型：
--
作者：
Meng, Shengbin;Sun, Jun;Guo, Zongming
为了应对带宽波动带来的挑战，改善在线视频的观看体验，在H.264/AVC可伸缩视频编码(SVC)扩展的基础上，提出了一种能够根据网络实际情况调整视频质量的自适应视频流系统。首先，提出了一种简单有效的线性误差模型，并对SVC的质量可伸缩性进行了验证。该模型利用了像素值误差的线性特征，可以准确地估计在SVC码流中丢弃任何组合的增强数据包所造成的失真。在此基础上，设计了一种类贪婪算法，根据数据包对码率失真(R-D)的影响为每个数据包分配一个优先级值，从而在一定的码率约束下实现R-D优化的码流提取。最后，利用比例积分导数(PID)方法对视频质量调整进行控制，确定合适的传输码率。通过监测和预测过去、当前和未来的带宽信息，基于PID的质量控制算法能够在保持高质量水平的同时减少质量波动。实验结果表明，与基线软件相比，集成上述算法的视频质量波动小得多，PSNR方差从1.24降至0.69，同时视频质量更高，PSNR平均提高0.83dB。
To cope with the challenges brought about by bandwidth fluctuation and improve the experience of watching online videos, an adaptive video streaming system that can adjust video quality according to actual network conditions is proposed based on the scalable video coding (SVC) extension of H.264/AVC. First, a simple and effective linear error model is proposed and verified for quality scalability of SVC. The model exploits the linear feature of pixel value errors and can be used to accurately estimate the distortion caused by discarding any combination of enhancement data packets in an SVC bitstream. On that basis, a greedy-like algorithm is designed to assign each data packet a priority value according to its rate-distortion (R-D) impact, thus enabling R-D optimized bitstream extraction under certain bitrate constraints. Finally, the proportional-integral-derivative (PID) method is utilized to control the video quality adjustment and determine a suitable bitrate for transmission. By monitoring and predicting the past, current, and future bandwidth information, the PID-based quality control algorithm is able to reduce quality fluctuation, while still preserving a high quality level. Experimental results show that compared with the baseline software, the proposed system that integrates the above algorithms can achieve much lower video quality fluctuation, with PSNR variance reduced from 1.24 to 0.69, and at the same time deliver higher video quality, with the PSNR average increased by 0.83 dB.