一种自适应的基于中心偏置特性的矩形搜索方法

摘要

H.264编码标准中为了得到更高的压缩比,针对计算量比较大的运动估计部分,采用了六边形运动估计算法.与全搜索算法相比,六边形算法减少了搜索时间,但是,六边形算法采用了固定的模板及固定的搜素步骤,没有充分的利用到视频图像的中心偏置特性.充分利用视频图像的中心偏置特性,提出了一种新的矩形搜索算法,使搜索具有自适应特性,试验表明,在图像质量保持不变的条件下,该算法的搜索速度大幅提高.%In H.264 video coding standard, in order to get higher compression ratio, HEXBS algorithm is employed to motion estimation, but the calculation work is very large. Compared with Full Search algorithm, it reduces the searching time obviously, but it takes fixed module and fixed searching step, which doesn't take full advantage of center-bias characteristic of video sequence. Based on this observation, this paper proposes a new search algorithm named Rectangle search Algorithm, and the search algorithm is adaptive. At the end of the paper, the proposed algorithm has been experimented. The results show that the searching speed has largely increased while maintaining the same quality of image.