A Novel Fast Intra Prediction Algorithm Applied in H.264/AVC

In H.264/AVC, a novel criterion named the rate distortion optimization (RDO) is employed to select the optimal coding modes for each macroblock (MB) within the intra prediction coding pictures, which can achieve a high compression ratio while leading to a great increase in the complexity and computational load unfortunately. In this paper, a DCT-based energy function is proposed, which is used to estimate the textural complexity of residual blocks of intra prediction. Then not more than 4 modes instead of 9 intra prediction modes for 4times4 block can be chosen to perform RDO according to the textural complexity of residual block. Consequently, the complexity decreases significantly. Experiments show that the proposed algorithm can save about 48% of the computation time stably while maintaining the PSNR-Bitrate performance of H.264/AVC.