第18卷
第12期
2010年12月
文章编号
1004-924X(2010)12-2672-08
光学精密工程
Optics and Precision Engineering
Vol.18No.12
Dee.2010
编码质量与容错性自适应的跳顿视频转码
周怡然，陈耀武
（浙江大学数字技术及仪器研究所，浙江杭州310027）
摘要：为了使跳赖视频转码在有较好编码质量的同时兼顾转码后新码流的容错性，研究了一种编码质量与容错性自适应的跳赖视频转码方法。提出了基于最优编码质量的跳顿转码算法，依据质量影响系数，在所设计的滑动窗结构中进行了最优跳模方案的选择，即计算各种跳顿可能性对编码质最的影响，最大程度地保留并编码运动强度较大的顿，提升编码质量。基于此算法，估计跌赖后的错误敏感度和错误影响系数，进一步提出了编码质量与容错性自适应的跳赖方法，使压缩效率和容错能力之间达到动态平衡。实验结果表明；丢包传输时.本方法可使再次解码视频的PSNR值提高0.05
～1.2dB，从面满足跳赖视频转码对顿率准、质量好、容错性强等方面的要求。关键词：视频转码；疏懒；编码质量：容错；时或分辨率
中图分类号：TN919.8
文献标识码：A
doi:10,3788/()PE.20101812.2672
Frame skipping video transcoding based on adaptation
of both encoding quality and error resilience
ZHOU Yi-ran, CHEN Yao-wu
(Institute of Advanced Digital Technology und Instrumentation,
Zhejiang University,Hangzhou 310027,China)
Abstract: In order to balance the encoding quality and error-resilience after video transcoding, a frame skipping video transcoding method based on the adaptation of both encoding quality and error resili-ence was researched. Firstly, a frame skipping transcoding algorithm based on the optimum encoding quality was introduced, in which the best frame skipping approach in a sliding window was selected based on a quality impact index. That means the method is to calculate the impacts of different frame skipping approaches on the coding quality and to preserve and encode the frames with larger motion in-tensities to improve the encoding quality. Following this frame skipping algorithm, the error sensitivi-ty and the error impact index due to the frame skipping were also caleulated and evaluated, then a frame skipping method based on thc adaptation of both encoding quality and error resilience was pres-ented to implement the dynamic balance between the coding efficiency and the error-resilient capabili-ty. Extensive experiments prove that thc Peak Signal Noise Ratio( PSNR) of re-decoded video can be improved by O. 05-1. 2 dB with the proposed method when the data transmittion is with packet losses. For mobile systems and devices. the proposal can meet the needs of accurate frame rate, good quality,
收稿日期：2010-04-26；修订日期：2010-05-141.
基金项目：浙江省重大科技攻关资助项日（No,2006C11200，2009C11035）