变换域Wyner-ziv视频编码的码率控制

为了降低变换域Wyner-Ziv 视频编码的解码复杂度,利用信道相关特征量及系数带的时间相关性提出了一种有效的码率控制算法.该算法在编码仨计传送的最小码率块,并利用不同系数带的时间相关性及信道的平均反馈次数,对估计的最小码率进行调整,得到实际需要传送的初始码率,从而有效地控制解码反馈次数,降低系统延时和解码复杂度.实验结果表明,该算法在保证编码效率的同时可以大幅度降低解码复杂度,最大可降低82%.

Rate Control for Transform Domain Wyner-Ziv Video Coding

Wyner-Ziv video coding is a typical distributed video coding paradigm. Current solutions in the literature perform rate control at the decoder by making use of the feedback channel (FC), and this will definitely cause huge complexity for decoding and constrain its application. Based on analyzing the impact that different motion activity would have on video coding rate, an effective rate control algorithm is proposed by utilizing the correlation noise statistical model, characteristic of feedback channel and temporal correlation. First, the encoder estimates the minimal number of rate chunks, then adjust minimal rate chunks according to the average number of requests and temporal correlation among coefficient bands. Then it would be easily to obtain suitable initial rate chunks, and consequently control the requesting times and complexity of decoder. Experimental results showed that this algorithm greatly reduce decoding complexity than others which have nearly the same coding efficiency.