中文摘要：

分数像素精确运动估计的改进是整个运动估计模块优化的关键,本文提出了基于H.264的内容自适应分数像素运动估计算法。首先,提出基于平坦区域宏块预测的无效分数像素运动矢量（MV）搜索省略算法（SMBP）;然后,改进H.264采用的基于中心的分数像素搜索算法（CBFPS）,提出基于预测矢量的增强型菱形模板（EDSP）搜索算法。实验结果表明,内容自适应分数像素运动估计算法比分数像素全搜索算法（FFPS）在峰值信噪比（PSNR）有微小降低（0.095～0.209 dB）的情况下,平均减少了75.6%的分数像素搜索点,整个运动估计模块平均节省了38.5%的计算量。

英文摘要：

In the H.264 video coding system,fast integer motion estimation algorithms have been fully developed,however,the fractional pixel motion estimation has become more comparable to that of the integer case.A content adaptive fractional pixel motion estimation algorithm is proposed in this paper.First,based on the smooth macro-block prediction,an algorithm to skip ineffective fractional pixel search is proposed.Then,to further reduce the computation load of H.264 fractional pixel motion estimation,an extended diamond pattern search algorithm based on predicted motion vector is proposed.The simulation results show that compared with the full fractional pixel search（FFPS） algorithm,the proposed algorithm can reduce about 75.6% fractional pixel search points,and save about 38.5% computation load of the whole motion estimation module and only with 0.095～0.209 dB PSNR degradation.