Abstract: In this paper, a new efficient intra-prediction algorithm for H.264/AVC is proposed to reduce the computational complexity of H.264/AVC intra-prediction, the proposed algorithm selects the best prediction mode from Intra4×4 and Intra16×16 based on the information entropy of the image block to be predicted and then utilizes edge direction information to reduce the nine kinds of the Intra4×4 mode to four kinds. The performance of the proposed algorithm is evaluated using the reference software JM8.4 from Joint Video Team(JVT). Experimental results show that the proposed algorithm is about 50% faster than Rate distortion optimised (RDO)method with a few extra bits(1.4% )and a slight decrease(0.058dB) in PSNR.

Key words: H.264, RDO, intra-prediction, information entropy

摘要： 本文基于图像的信息熵和边缘方向信息针对H.264的帧内预测算法计算复杂度高、不适合于实时应用的弱点，提出一种新的帧内预测快速算法。该算法利用图像的信息熵从Intra4×4与Intra16×16两种预测模式中选择一种最佳预测模式，利用边缘方向信息将Intra4×4的9种模式选择降为4种，并利用JVT公布的测试平台JM8.4进行了实验仿真。实验结果表明，该算法在码率平均增加1.4%，峰值信噪比平均下降0.058dB的情况下，能缩短编码时间50%左右，是一种快速的H.264帧内预测算法。

关键词: H.264, 率失真优化, 帧内预测, 信息熵