一种基于H.263的混合错误掩盖方法

由于通信系统信道不可避免地存在噪声，传输数据流必然存在误码，特别是在H．263的视频码流中，即使一个比特的错误，常会影响一个区域的图像不能正确解码，且错误还会扩散到后续数帧图像，从而导致解码图像质量的严重恶化。该文在对现有的错误掩盖方法分析的基础上，提出了一种混合错误掩盖方法，它能根据运动向量的大小，自适应地采用空域掩盖算法或时域掩盖算法。该方法既考虑了图像的空间相关性，又考虑了时间相关性。模拟实验结果表明，采用该方法既改善了解码图像的质量，又降低了实现的复杂性，能够满足一定的适时处理要求。

A New Hybrid Error Concealment Method Based on H.263

The reconstructed image quality can be degraded substantially by errors during the transmitting over communication channel, especially in H.263, which leads to error propagation in frame sequence. Based on the discussion on error concealment method used at present,this paper presents a new hybrid error concealment method ,which can adaptively use the spatial concealment algorithm or temporal concealment algorithm according to moving vector. The advantage of this method is its considering both spatial correlation and temporal correlation. The simulation shows that the image quality is significantly improved, and the implementation complexity can be reduced too.