为了减少视频编码失真,论文提出了一种新颖的视频编码失真补偿方法——两步补偿法。该方法优先补偿解码恢复图像的直流失真,再利用直流补偿后的恢复图像设计维纳滤波器,进一步减弱解码恢复图像中的交流失真。实验数据表明两步补偿法的编码效率优于现有自适应环路滤波方法,提高H.264/AVC的编码效率最高可达26.31%。此外,利用分析得到的交流补偿滤波器系数和为1的特点,提出相应的滤波器系数的量化编码方法,去除了滤波器系数表示方法中的冗余。
To reduce the distortion in the video coding,the two-step method for distortion compensation in video coding is proposed.Firstly,the DC offset of the reconstructed picture is compensated.Then,the adaptive compensation filter is designed for processing the picture to reduce further AC part of the distortion in the video coding.Experimental results demonstrate that the two-step distortion compensation outperforms the existing algorithm of adaptive loop filter with different resolution sequences.The coding efficiency is improved up to 26.31% compared with H.264/AVC.In addition,with the feature that the sum of the tap coeffients of the adaptive compensation filter equals 1,the modified algorithm for quantization and codec of the filter coefficients is proposed.The redundancy of the description of the filter coefficients is reduced.