H.264/AVC performs rate-distortion optimization (RDO) in order to select the best coding modes with best coding efficiency. However, computation complexity is also increased. In this paper, a fast intra mode decision algorithm is proposed. With both t...
H.264/AVC performs rate-distortion optimization (RDO) in order to select the best coding modes with best coding efficiency. However, computation complexity is also increased. In this paper, a fast intra mode decision algorithm is proposed. With both the magnitude and the orientation of the local edge information, most proper block mode is selected from 4×4, 8×8 and 16×16 block modes. Then by the edge information obtained from previous step, candidate prediction modes are decided for the chosen block modes. The number of modes investigated in RDO can be reduced to 36 or 48 in common case instead of 736 in full search. Simulation results show that the proposed algorithm saves about 75% coding time with negligible PSNR loss and bit-rate increase compared with full search.