Wyner-Ziv视频编码中的码率控制算法研究  

The research on rate control algorithm for Wyner-Ziv coding

作　　者：檀会娟 唐加山[2] 

机构地区：[1]南京邮电大学通信与信息工程学院,江苏南京210003 [2]南京邮电大学理学院,江苏南京210023

出　　处：《微型机与应用》2015年第10期38-40,47,共4页Microcomputer & Its Applications

摘　　要：分布式视频编码系统中,现有码率控制方法大致分两类,一种是基于反馈信道,另一种是基于无反馈信道。基于反馈信道码率控制算法虽然可以获得较高的解码质量,但是时延大;相反,无反馈信道码率控制算法时延小、实时性高,但是有损解码质量。为解决这一矛盾,阐述一种混合码率控制算法,即在编码端先估计出较小的码率,当解码失败时,解码端才利用反馈信道向编码端请求更多的校验比特直到解码成功。实验结果表明,在相同目标码率下,与有反馈码率控制算法相比,该算法所需反馈次数有所减少;与现有无反馈码率控制算法相比,对于不同视频序列解码帧的峰值信噪比均有不同程度的提高。Recently, there are almost two approaches of rate control in distributed video coding, namely rate control with and without feedback channel. Although we can get a higher quality image through the former, it can cause much time delay. Oppositely, rate control without feedback channel will decode frame fast, but it may cause failure frame at the decoder. To solve the problem, this paper proposes a way of hybrid ＇rate control, which will make a rate estimation at the encoder firstly. Once decoding failure, the decoder will request more parity bits from the encoder with feedback channel. Simulation results show that the proposed method will decrease the number of request by the decoder compared with the rate control based on feedback channel and get a high PSNR value compared with the current rate control without feedback channel.

关 键 词：分布式视频编码 码率控制 Wyner—Ziv编码 反馈信道 

分 类 号：TN919.8[电子电信—通信与信息系统]