Abstract: Gives a algorithm which uses K－means algorithm to iterate and cluster, and uses the clustering results to build up color image palette. The algorithm based on the statistic of the appearing times of all colors RGB combination value, uses the 256 color from cluster to build up palette, and tranforms the BMP format-pattern into GIF formate. The experiments show that the transform has less color distortion.

Key words: clustering, palette, K－means algorithm, color distortion