关键词: H.264/AVC, 帧内预测, 率失真优化（RDO）, 主要边缘强度（KES）, 边缘特征, VLSI

Abstract: To reduce the computational complexity of intra-prediction mode decision for H.264/AVC,a new fast Intra mode decision algorithm based on Rate Distortion Optimization（RDO） technology has been proposed in this paper.To reduce the number of intra-prediction mode,some candidate modes are selected based on the edge features or Key Edge Strength（KES） of the image,and then related RDO is calculated.Luma block and chroma block are separately optimized to reduce the computational complexity.Experimental results have shown that cost time of the proposed fast intra-prediction algorithm is down to about 25% of that of original algorithm cost with negligible PSNR degradation and slight bit-rate increase.Compared with the PAN’s Sobel operator based edge detection algorithm,the proposed algorithm requires lower coding time and increases PSNR while keeping bit rate almost unchanged.Besides,the proposed algorithm is much easier to VLSI implementation.

Key words: H.264/AVC, intra-prediction, Rate Distortion Optimization（RDO）, Key Edge Strength（KES）, edge feature, VLSI