运用H.264/AVC宏块编码特征的低复杂度率失真优化算法  

A low complexity rate distortion optimization algorithm for H.264/AVC using coding characteristic of macroblock

作　　者：张庆明[1] 彭强[1] 

机构地区：[1]西南交通大学信息科学与技术学院,成都610031

出　　处：《中国图象图形学报》2011年第5期733-739,共7页Journal of Image and Graphics

基　　金：国家自然科学基金项目(60972111)

摘　　要：分析H.264/AVC各帧间编码模式与最佳模式编码同一宏块(MB)时在比特率、参考帧选择及CBP(codedblock pattern)上具有的相似性,对MB各最佳编码模式的比特率和CBP分布进行了统计,根据统计结果分析出比特率和CBP相结合能对编码模式进行比较准确的区分定位。并由此提出一种联合参考帧选择和模式选择的低复杂度RDO(rate distortion optimization)算法。算法利用P16×16模式编码得到的比特率和CBP来确定候选编码模式,用P16×16模式的参考帧来确定其余帧间模式的参考帧。最后将候选模式在候选参考帧中进行运动估计和编码模式的RDO,选出最佳编码模式。实验结果表明,提出算法与H.264/AVC参考软件JM12.0相比,平均比特率增加1.32%、亮度PSNR减小0.075 2 dB,编码时间减少71.20%。In this paper, the similarities of bits, reference frame selection and coded block pattern（CBP） of a coding macroblock（MB） between each inter mode and optimal mode have been investigated. The bits and CBP＇s distribution characteristics of a MB which encoded by the optimal mode have been analyzed, and the result shows that the coding modes can be differentiated by bits and CBP. Based on these characteristics, a novel low complexity rate distortion optimization （RDO） algorithm which combination reference frame selection with mode selection RDO is proposed. This algorithm utilizes P 16 x 16 mode＇ s reference frame to select the candidate reference frames for other inter coding modes, and the candidate modes are selected by bits and CBP of mode P 16 x 16. The optimal mode will be selected in all candidate reference frames and candidate modes with RDO. The algorithm is evaluated using a wide range of test sequences of different classes. Comparing with RDO in JM12.0, the experiments results demonstrate a reduction coding time 71.20% in average with 1.32% of bits increase and 0. 0752dB of Luma PSNR loss.

关 键 词：视频编码 率失真优化 宏块编码特征 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]