Restoring halftoned color-quantized images with simulated annealing

Restoration of color-quantized images is rarely addressed in the literature, especially when the images are color-quantized with halftoning. Direct applications of existing restoration techniques are generally inadequate to deal with this problem. A restoration algorithm based on simulated annealing is proposed to solve the problem. This algorithm makes a good use of the available color palette and the mechanism of a halftoning process to derive useful a priori information for restoration. It is shown to be able to provide a good restoration result.