基于曲面拟合的H.264错误掩盖方法

视频流的传输错误将会导致解码错误在时间和空间上扩散，直接影响重构图像的质量。充分结合了H.264的编码特性，利用宏块的空间、时间相关性来确定丢失宏块的类型. 根据相邻块的运动矢量，利用Shepard方法拟合一个曲面，较精确地计算出了丢失宏块的运动矢量，从而提高了重构图像的质量。仿真结果表明, 该算法优于以往的边界匹配算法，在同等宏块丢失率下，恢复的视频序列Y分量的 峰值信噪比(PSNR)值能提高0.75~1.5dB。

A Method of Video Error Concealment in H.264 Based on Surface Fitting

Transmission error of video frequency always results in decoding mistake both in time and space and directly affects the quality of reconstructed image. This paper describes a new error concealment method for H.264. With the strong correlation of time and space between neighborhood macroblocks, the type and size selection of the lost block through the neighborhood blocks was estimated rightly. On the basis of the division result, a Shepard method constructed a surface was proposed to predict the motion vectors of the lost macroblock more exactly, and also improved the quality of the reconstructed image. The simulation result showed: this algorithm is better than usual boundary matching arithmetic. Under equal macroblock lost rate, the Y weight peak signal-to-noise ratio (PSNR) of video recovered by this proposed method could increase 0.75~1.5dB.