一种改进的自适应增强型时域错误隐藏算法

An improved adaptively enhanced temporal error concealment algorithm

考虑到错误块的处理次序对隐藏图像质量的影响,提出了一种改进的自适应增强型时域错误隐藏算法。该算法利用相邻正确信息或隐藏后的信息,不断估算错误宏块(MB)的次序值,每次选择恢复次序值最大的错误MB。在隐藏错误MB时,首先判断其分割模式及其子宏块(SMB)的隐藏顺序,再根据帧内平均运动矢量大小,自适应地选择基于纹理的单边重叠边界匹配算法(TBSS-OBMA)或基于纹理的双边重叠边界匹配算法(TBDS-OBMA),从候选运动矢量(MV)中找出该MB或SMB的最佳恢复MV。通过性能比较和具体实验效果分析,此算法能够在高误码率下更好地提高错误图像质量,就PSNR来说,比参考软件JM12.2中采用的隐藏算法可提高1.16dB。

The processing order of error blocks has an important effect on the improvement of concealed image quality, an improved adaptively enhanced temporal error conceahnent algorithm is thus proposed. The algorithm continuously estimates the order value of error macrobloek（MB） using the received or concealed adjacent information, and only the error MB with the largest order value is restored at each time. When conceals an error MB, firstly we determine its partition mode and the concealed order of its sub-macroblock（SMB） , then chooses the best motion vector（MV） for the error MB or SMB from the candidate MVs, by adaptively use the single-sided or double-sided overlapping boundary matching algorithm based on texture（TBSS-OBMA or TBDS-OBMA）. The experiment results show that the proposed algorithm can improve the quality subjectively or objectively aspect in the same error environment, and the improvement of 1.16dB in PSNR can be achieved comparing to JM12, 2.