Evaluation of postprocessing stages for wavelet-compressed image enhancement based on a simple perceptual criteria

We present the results of a preliminary study of enhancement of images that have been degraded by lossy wavelet coding algorithms. In this preliminary study we tested a large set of (nonlinear) image enhancement algorithms. The results have been evaluated using a simple objective criterion, which has been found to have reasonable correlation to subjective quality estimation for wavelet-degraded images. We first discuss some of the aspects of lossy wavelet coding and the associated degradation. Then we briefly outline the proposed quality measure. Finally we present the postprocessing algorithm which was found to be optimal for image enhancement after the abovementioned kind of degradation.