Multiresolution histogram analysis for color reduction

A new technique for color reduction is presented, based on the analysis of the histograms of an image at different resolutions. Given an input image, lower resolution images are generated by using a scaling down interpolation method. Then, peaks and pits that are present in the histograms at all resolutions and dominate in the histogram of the input image at full resolution are taken into account to simplify the structure of the histogram of the image at full resolution. The so modified histogram is used to define a reduced colormap. New colors possibly created by the process are changed into the original colors closer to them.