【作者】 林学如； 蔡灿辉；

【Author】 Lin Xueru,CAI Can-hui (School of Information Science and Technology,Huaqiao University,Quanzhou 362021)

【机构】 华侨大学信息科学与工程学院；

【摘要】 帧间模式选择是H.264编码器中最耗时的部分。本文提出一种基于相邻宏块预测模式和运动特征的新的快速模式选择算法。该算法先计算出当前宏块在SKIP模式下的率失真开销(RDcost),根据该RDcost跟预设阈值的比较结果确定是否提前中止搜索;否则再根据相邻宏块的先验预测模式和运动特征估计当前宏块的编码模式,从而大大加快了帧间模式选择过程。实验结果表明,本文算法能够极大提高帧间模式选择的速度,并且带来的PSNR损失和码率增加几乎可以忽略。更多还原

【Abstract】 Inter-frame mode decision is the most time-consuming part in H.264.A novel fast mode decision algorithm based on predicted mode and motion activity is proposed in this paper.Firstly,the RD cost of current MB at SKIP mode is computed for a possible early termination.Otherwise,current MB’s encoding mode is decided based on the mode and motion activity of neighbor macroblock.Accordingly,the process of inter-frame mode decision can be accelerated greatly.The experimental results have shown that the proposed algorithm can speed up inter-frame mode decision greatly and loss in PSNR and increment in rate incurred can almost be neglected.更多还原