Overlapping Interval Differences-Based Fast Intra Mode Decision for H.264/AVC

An efficient and fast mode decision algorithm for H.264/AVC Intra prediction is proposed in this paper. Overlapping interval differences (OID) are calculated in the domain composed of samples of current block and reconstructed samples of neighboring blocks. The OID can represent the direction error of each prediction mode. Smaller direction error means that the corresponding prediction mode will be considered as the final selection with high probability by rate-distortion optimization (RDO). So this method adopts a subset of the candidate modes instead of all to implement the efficient and fast encoding. Experimental results show that the proposed scheme can reduce about 30% computational complexity with negligible degradation of video quality and compression efficiency. Compared with other approaches in the literature, the proposed algorithm also shows better performance.