基于相关性的H.264自适应模式判决算法*

提出了一种基于时空相关性的H.264自适应模式快速判决算法。该算法首先根据前帧已编码宏块各模式的比率大小顺序来确定当前宏块模式判决顺序；利用前帧中宏块编码模式的平均率失真及当前帧的图像复杂度自适应地预测当前帧宏块相应编码模式的阈值。实验表明，本算法平均可以节省编码时间75%以上,同时PSNR下降约为0.07 dB,有利于实时应用。

Adaptive mode decision algorithm for H.264 based on correlation

This paper proposed a fast adaptive mode decision algorithm based on spatial-temporal correlation. The mode decision order of current MB was determined by the order of the ratio of coded MB modes in previous frame. It calculated each average rate- distortion cost of the related mode in pervious frames and the image complexity.Then,used them predicate adaptively the decision threshold of related mode for current MB to determine whether to terminate early. The experimental results show that the proposed method can save the encoding time up to 75% on average with 0.07 dB performance degradation that can be used in real-time applications.