【作者】 邹伦开；

【导师】 王宏远；

【作者基本信息】 华中科技大学 ， 通信与信息系统， 2006， 硕士

【摘要】 H.264是联合视频组JVT(Joint Video Team)于2003年3月发布的新一代视频压缩标准。H.264标准支持从低带宽、高误码率的无线移动视频通信到高码率、低延时的视频广播及在线流媒体等多种应用,因此日益受到业界的关注。为了实现更高的压缩效率,H.264标准采用了多种新的编码技术,如多参考帧预测,变块尺寸运动估计,整数变换、基于上下文的熵编码等。这些新技术在提高压缩比的同时也大大增加了编解码的复杂度。针对此问题,本文就编码端的运动估计和解码端的运动补偿算法展开了研究。本文首先介绍了视频编码的一般原理,回顾并对比了先前发展的H.26x系列和MPEG系列视频编码标准;然后论述了率失真优化的数学原理及其在视频编码标准中的应用;接下来,本文在研究前人算法的基础上,提出了两种新的快速运动估计算法:一种是基于子块叠加的多模式运动估计,一种是基于逐次淘汰的多模式运动估计,两者都采用率失真优化准则,与普通全搜索算法相比,新提出的两种算法速度大大提高,而结果精度不变;最后,本文又提出了一种新的应用于解码端的运动补偿算法,简化了解码端运动补偿模块的设计,为解码器的硬件实现提供了方便。更多还原

【Abstract】 H.264 video coding standard is formally published by JVT(Joint Video Team) in March 2003. This standard is designed to give a solution for a various applications, such as very low bit rate video communication with high error rate, and high bit rate entertainment quality broadcast, interactive video-on-demand services etc. Therefore it is concerned growingly by the industry. In order to achieve higher compression ratio, the H.264 standard adopts many new coding skills as followed: multiple reference picture, variable block-size motion estimation, short word-length integer transform, context adaptive entropy coding. While achieving high compression ratio with these new skills, the complexity of the codec is also greatly increased. Aiming at this problem, this paper researches the motion estimation algorithm and motion compensation algorithm used in the coders and decoders.Firstly, the general principles of video coding are introduced. Then, the already developed H.26x series and MPEG series standards are recalled and compared. And the rate distortion optimization and its application in video coding are discussed subsequently. After that, this paper proposed two new fast motion estimation algorithms based on the previously developed methods. The first one is a multimode motion estimation based on block summation algorithm. And the other one is multimode motion estimation based on the successive elimination algorithm. Both of these algorithms use rate distortion optimization guidelines and increase the estimation process a lot without any quality decrease. At last, another motion compensation algorithm used in the decoding process is proposed. With this algorithm, the motion compensation module in a hardware design can be simplified.更多还原