基于反馈的自适应参考帧选择的率失真优化分析

Rate-Distortion Analysis for Feedback-Based Adaptive Reference Picture Selection

为了提高数字视频实时传输的容差能力,该文提出了一种基于反馈的自适应参考帧选择方法。在传统参考帧选择优点的基础上,设计了一种新的通过率失真技术优化选择参考帧的帧间帧预测结构,分析了选择不同参考帧编码时的编码码率以及它对编码失真的影响。引入了信道代价均值的概念,探讨了信道误差的扩散过程及其对信道失真的影响。在联合信源和信道的率失真优化框架内,选择使得率失真代价最小的候选参考帧作为当前帧编码的参考帧,有效地改善了视频传输质量,并减少了编/解码器所需缓存的参考帧。仿真实验显示自适应参考帧选择的PSNR性能在不同码率和丢包率下均优于经典的ACK和NACK参考帧选择方法。

A feedback-based Adaptive Reference Picture Selection （ARPS） is proposed for improving error resilience in real-time video transmission. The novel predictive structure which the reference picture selection can be optimized with rate-distortion method is designed by taking advantage of classic reference picture selection. The bit-rate of coding with difference reference pictures is analyzed, and its impact on source distortion is discussed. By first introducing the concept of average channel cost, the propagation of channel error and its impact on channel distortion is studied. Within joint source-channel rate-distortion optimization framework, the video picture that leads to the minimum rate-distortion cost is selected as the current reference picture, which can efficiently enhance the video transmission quality and decrease the number of reconstruction frame buffers of encoder/decoder. Simulation results show that the proposed ARPS algorithm outperforms the classical ACK and NACK RPS method in different bit-rates and lost-rates in PSNR.