In an image printed by a printing apparatus, graininess particularly in a light part of the printed image is reduced by relatively simple structure by using a second color. To do so, magenta and cyan color component data in image data is subjected to under color removal to generate image data of a blue...http://www.google.de/patents/US6530638?utm_source=gb-gplus-sharePatent US6530638 - Image processing apparatus, printing apparatus and storage medium
