压缩图像清晰度的增强研究

Study on enhancement of the definition of compressed image

对视频编码系统的变换和量化过程的研究表明：基于ＤＰＣＭ和ＤＣＴ标准的编解码系统，在低码流时，由于较大的量化步长，高频成分量化不精确而损失较多，必然会造成解码图像的模糊。针对图像高频损失，应在解码图像后处理时合理地进行高频成分补偿。提出了一种可行、有效的图像清晰度增强方法。对解压缩图像的实验表明主观效果有明显地改善。

After the analysing of video codec system, we found that the system based on DPCM and DCTalways induct blur in decoded image. Because, the step size of quantizer is big in low bit rate, so main part ofcomponents of high frequency is lost. Aimed at high frequency loss, the compensation of components of high frequency showld be adcped during post processing of codec video in this paper, we present a practical and effectivemethod to retrieve the high frequency. In experiment, we get a good result.