An efficient fast mode selection for intra prediction

In order to maximize the coding performance, H.264 adopts RDO (rate distortion optimization) at the cost of a very high computational complexity. A special focus is spent on fast intra prediction mode selection in this paper. To reduce complexity associated with intra prediction mode selection, an efficient fast mode selection for intra prediction is proposed. First, the Pan´s fast algorithm based on edge direction histogram is improved. Second, a new improved algorithm is joined together with a 4´4 intra prediction mode selection algorithm based on the feature of the reference pixels. Experimental results show that, compared with the H.264 encoder JM61, the proposed scheme reduces 58% coding time for I-frame while maintaining the PSNR and only increasing bit rate a little. Furthermore, compared with Pan´s scheme based on edged direction histogram, the proposed scheme reduces 24% coding time for I-frame while maintaining similar PSNR and bit rate.