H.264中快速运动估计UMHexagonS算法的改进

Improvements on fast motion estimation UMHexagonS algorithm of H.264

在对H.264中非对称十字型多层次六边形格点搜索算法(UMHexagonS)研究的基础上,针对其存在运算量大、耗时等问题提出两方面的改进。首先,利用对称十字模板替换原来的5×5螺旋搜索,减少了64%的搜索点数;其次,利用对象内部代价的相关性提出自适应搜索长度方法,以减少运算量。在JM10.1测试模型上进行了验证。实验结果表明,改进算法在保证图像质量的前提下,可以有效地减少平均15%的运动估计时间,提高了总体的编码性能。

Based on introducing an unsymmetrical cross grid search algorithm （UMHexagonS） of H.264, improvements the algo- rithm in two areas for the existence of large amount of computation, high complexity, time-consuming issues. Firstly, uses symmet- ric cross template replace the original 5×5 spiral search, decreases 64% of search points. Secondly, uses correlation of object inside cost, propose adaptive searching range method and reduce computation. In JM10.1, the experiment results show that the improved algorithm in the premise of image quality can effectively reduce average 15% of the motion estimation time, thus improving the overall coding performance.