An Efficient Scheme for Intra Prediction Block Size and Mode Selection in Advanced Video Coding

In H.264/MPEG-4 Advanced Video Coding (AVC) variable block-sized intra prediction modes are used in intra and inter frame coding to improve coding efficiency. In order to achieve best prediction mode a robust rate-distortion optimization (RDO) technique is employed for each macroblock (MB). The use of RDO process drastically increases the computational complexity of the encoder because of the large combinations of coding modes. This paper presents an efficient scheme based on spatial homogeneity measures to decide appropriate block size for intra prediction and to exclude as many intra prediction modes as possible prior to the RDO process. Experimental results show that the proposed scheme speeds up the encoding process by 69% without significant degradation in video quality.