Fast H.264 selective intra mode decision for inter-frame coding

Despite its remarkable coding efficiency, the computational complexity of the spatial-domain intra prediction scheme of H.264 remains a challenging issue especially for applications of the high profile, as it incorporates the additional intra 8times8 prediction mode. To address this issue, we propose in this paper a fast selective intra mode decision algorithm that exploits a newly discovered property of inter-frame coding that the difference in rate-distortion cost between the best inter mode and the intra 16times16 mode is highly related to the type of the best coding mode. The proposed algorithm has high prediction accuracy, low computational overhead, and negligible effect on PSNR and bit-rate. Performance comparison is provided to show the superiority of the algorithm.