H.264快速自适应帧间编码模式选择算法

Fast Adaptive Inter Mode Decision Method for P Slices in H.264

提出了一种针对H.264标准的帧间编码模式快速自适应选择算法用以减少编码器的复杂度。该算法利用运动补偿后残差宏块的统计信息,将需要计算率失真代价函数的候选模式减少为一个模式组中包含的模式子集。由于该算法采用了重叠划分的模式组以及动态调整的门限,可以最大可能保证宏块的最佳编码模式处于所选择的模式组中,所以可以在编码质量下降很小的情况下,大幅度降低编码复杂度。实验表明,本算法平均可以节省编码时间52%,同时PSNR下降约为-0.05dB,不会影响主观视觉效果。

In this paper, a fast adaptive inter modes decision method is proposed to reduce the complexity of H.264 encoder. The candidate inter modes used in rate distortion optimization can be limited in a small mode group （MG） by using the characteristics of the motion compensated residual image. The overlapped mode groups and dynamic adjusted thresholds adopted in the proposed method can make the best mode lies within the chosen MG with great possibility which leads to extensively computation reduction without any perceivable loss in quality. The experimental results show that the proposed method can save the encoding time up to 52% on average with -0.05dB performance degradation that is negligible.