A content adaptive fractional pixel motion estimation algorithm for H.264

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.