摘要
H.264使用率失真优化提高了编码效率,但也增加了计算复杂度,不利于编码的实时实现。本文分析了H.264中计算复杂度较高的帧内预测模式选择部分,提出一种快速的帧内预测模式选择算法。根据隶属度函数预先判断宏块类型,通过求取各像素点的方向得到4×4块的纹理方向,由此确定候选模式,减少预测模式的数量。实验结果表明,在图像性能和码率基本保持不变的情况下,编码时间平均下降了约38%,大大提高了编码速度。
H. 264 adopts Rate Distortion Optimization （RDO） to enhance coding efficiency at the cost of a very high computational complexity, and it is difficult to be real-timely implemented. By analyzing the factors of the computational complexity of the intra- prediction mode decision, a fast algorithm for the intra-prediction mode decision is proposed. First, the type of the macro-block is decided based on the fuzzy membership function, and then the block texture direction is estimated. The number of prediction modes and the algorithm complexity are reduced effectively. Experimental results show that the proposed algorithm can improve the H. 264 encoding speed greatly without obvious PSNR change and bit-rate rise.
出处
《燕山大学学报》
CAS
2010年第1期56-60,共5页
Journal of Yanshan University
