Compensated sum of absolute difference for fast H.264 inter mode selection

In this paper, a new compensated sum of absolute difference (CSAD) for fast H.264 inter mode selection algorithm is proposed. The main idea is to determine the best inter mode based on CSAD cost instead of the rate-distortion (RD) cost. This approach can avoid most of the computationally intensive processes in the H.264 mode decision. The CSAD could solve the problem of SAD and SATD costs used in mode decision which normally bias to the smaller block size modes. It is because they are normally achieving higher prediction accuracy but consume more bit rate. Experimental results show that the proposed CSAD-based mode decision algorithm can reduce 60% to 68% of the H.264 total encoding time with negligible degradation in the RD performance.