基于纹理的H．264/AVC帧内预测块选择快速算法

Fast Intra-frame Prediction Algorithm Based on Texture for H.264/AVC

摘要: 针对帧内预测中的Intra_16×16、Intra_8×8及Intra_4×4预测块选择提出了一种基于纹理的快速帧内预测块模式选择算法.该算法的原理是在做帧内预测之前,首先利用方差对区域纹理的平滑度和粗糙度进行估计,然后从Intra_16×16、Intra_8×8及Intra_4×4中选择一种块进行模式预测.通过方差和阈值相结合的方法来决定块预测模式,减少了算法复杂度,提高了压缩效率.实验结果表明,当考虑Intra_8×8预测块时,编码时间减少了50%以上,当不考虑时,编码时间减少了20%以上.与此同时,码率和峰值信噪比(PSNR)基本保持不变.

Abstract: In this paper,a fast algorithm based on texture is proposed to select the mode of the intra-frame block prediction.The variance is at first used to measure the smoothness and coarseness of the texture,then the intra-frame mode is accordingly selected from Intra_16×16,Intra_8×8 and Intra_4×4.This algorithm combines the variance and the threshold,which remarkably reduces the time complexity and improves the compression efficiency.Experiment results show that the coding time can reduce above 50 %,Intra_8×8 included and the coding time can reduce above 20 96,Intra_8×8 not included,whereas the bit rate and the PSNR maintain similar.