Threshold decision method for subtractive color process for lossless compression

Non-photographed images such as cartoon image or illustration are often handled in PC. To reduce the number of bits of their compressed images, subtractive color are processed. We researched the methods of subtractive color processes that have a high encoding efficiency. However, our method is necessary to set three parameters. In this paper, we propose the setting method of the one of these parameters, and we evaluate the performance.