【作者】 陈良琴；

【导师】 陈新；

【作者基本信息】 福州大学 ， 通信与信息系统， 2005， 硕士

【摘要】 随着数字信息技术的飞速发展,人们对多媒体通信业务的需求与日俱增。视频压缩技术是实现多媒体通信应用的关键技术,而运动估计却是视频压缩技术的核心环节。本文就运动估计快速算法方面作了相关的研究,提出了几种基于块匹配的运动估计快速方法。本文首先阐述了基于块匹配法的运动估计基本原理,介绍了全搜索法和几种典型的运动估计快速算法,分析了各算法的特点,在此基础上总结了提高运动估计搜索效率的几个关键技术。接着重点介绍了本文提出的三种运动估计快速改进算法。基于全搜索的改进算法,是在全搜索的基础上尝试引入了连续排除算法、子抽样和终止条件来提高搜索速度,增强全搜索的实时性。一种新的分级塔式搜索法,该算法是在原有的分级塔式搜索法的基础上加以改进的,提高了运动估计搜索精度。基于预测起点的运动幅度判断搜索法,该算法利用块的时间相关性和空间相关性来预测搜索起点,根据块的运动幅度大小分别采用不同步长的搜索策略,搜索效率比较接近三步法,证明了根据块运动的特性以结合运用不同的搜索算法来研究有效的运动估计算法的可行性。最后本文通过实验得来的数据来定量地分析评价各快速算法的优缺点,对今后提出新的更有效的运动估计快速算法具有一定的参考价值。更多还原

【Abstract】 With the rapid evolution of digital information technology, the demand to the multimedia communication service increases steadily. Video compression technology is the key of implementing the multimedia communication service, and the kernel part of the video compression technology is motion estimation. This paper gives the correlative research on the motion estimation fast algorithm, puts forward several motion estimation fast algorithms based the block matching. Firstly, the paper expatiates the essence principle of the motion estimation based block matching, introduces Full Search method and several typical motion estimation fast algorithms, and analyzes each characteristic, then to sum up the key technology for increasing the motion estimation search efficiency; Secondly, it stress introduces three motion estimation fast improved algorithms: the improved algorithm based Full Search method, it imports successive elimination algorithm、subsample and termination condition to increase search speed for enhancing the real time of Full Search. A new hierarchical pyramid search method, which is from the old hierarchical pyramid search method, can improve the search precision. The motion scope judgement search method based prognosticating the search beginning point, it utilizes the time relativity and the space relativity of block to prognosticate the search beginning point, and adopts the different search pattern according to the block motion scope, the search efficiency is close to the Three Step Search, which proves the feasibility of researching the new efficient motion estimation algorithm according to the characteristic of block motion to use the different search methods; In the end, this paper evaluates the advantage and disadvantage of the different fast algorithms through the data get from the experiment, it will have some reference value to bringing the new and effective motion estimation fast algorithm in the later research.更多还原