基于DCT的错误隐藏算法的两种分块策略

基于DCT的错误隐藏算法可用于多媒体系统在客户端近似重建出错图像,该文提出了为配合这一重构算法而采用的两种图像分块处理模式———像素分块法和DCT块分块法。前者重建图像视觉效果较好,但压缩前分块减少了相邻像素间相关性,影响压缩效率,适用质量要求较高的场所。后者重建图像虽然有块状效应,但在压缩后处理不影响压缩效率,可以灵活改变分块数值,能获得更好的图像重建效果。

Two Image Partitioning Strategies for Error Concealment Algorithm Based on DCT

The error concealment algo ri thm based on DCT can reconstruct lost images approximately at client in the mul timedia system.Two image partition methods are proposed working for the recons truction algorithm-pixel partitioning scheme and DCT block partitioning scheme .The human perception for reconstruction image using former is better than that using latter.But pixel algorithm diminishes the relativity between adjacent pixels because it handles before the compression and also significantly affects the compression efficiency.The pixel partitioning scheme is fit for the occasi on which people need more better quality.For the latter,there are a few blocky zones in the reconstruction image,but it doesn't affect the compression effic iency as it does after the compression.So it can change the value of partitioni ng flexibly to get better image.