In order to maximize the coding efficiency

H.264 adopts RDO(rate distortion optimization) at the cost of a very high computational complexity.A special research effort is made 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 4×4 intra prediction mode selection algorithm based on the feature of the reference pixels is proposed

and then joined together with the improved Pan's algorithm.Experimental results show that

compared with the H.264 encoder JM61

the proposed scheme reduces coding time by 61%~66% for I-frame while maintaining the PSNR unchanged and increasing bit rate slightly.Furthermore

compared with Pan's scheme based on edged direction histogram

the proposed scheme reduces coding time 12%~33% for I-frame while keeping PSNR and bit rate almost unchanged.