Hardware oriented content-adaptive fast algorithm for variable block-size integer motion estimation in H.264

Motion estimation can reduce temporal redundancy and achieve high compression capability in video coding standards. In H.264, the coding gain is further improved by variable block-size motion estimation (VBSME). In order to reduce the complexity, many fast algorithms have been proposed. Though previous works can reduce a large amount of computation, most of them are not suitable for hardware implementation and not robust for complex motion videos. A content-adaptive fast algorithm for variable block-size integer motion estimation (VBSIME) is proposed in this paper. Motion activity is exploited to improve the coding efficiency. Because of the good data reuse scheme and simple control flow, the proposed algorithm is applicable to hardware implementation. According to the simulation results, about 98% searching candidates and 86% encoding time are reduced with at most 0.05 dB quality drop in average compared with full search even for complex motion videos.