H.264视频编码快速宏块模式选择策略

分析了表征前一帧各块运动特征的统计信息(包括各宏块误差值和运动矢量),并以该统计信息预测当前帧各块的运动特征,提出了一系列基于统计信息、宏块分类和自适应判决门限的提前选择某模式为最优模式的快速模式选择策略. 实验数据表明,快速算法能够以43%的计算时间,达到与JM12.2中原参考算法近似的峰值信噪比和码率性能.

Fast Mode Decision Strategy for H.264 Video Coding Standard

Fast mode decision is a key issue in real-time application of the H.264. In this paper, a new scheme of fast variable block size motion estimation with sub-pixel refinement is proposed. This algorithm uses the statistical information, which features the motion activities of the blocks in the previous frame, to predict the characteristics of the motion activities of the blocks in the current frame. Both distortion values and motion vectors of Macro Blocks(MB) in the previous frame are considered. With this prior knowledge, we can make decision on early rejection of sub-partition modes. Extensive experimental work has been done, results of which showed that the approach gives a speedup of 57% over that of thel algorithm in JM, with a negligible degradation in peak signal-to-noise ratio(PSNR) and bitrate.