Patent ID: 8610957

Claim:
An image processing method performed by an image processing apparatus that performs image processing to form an image on a printing medium by using colorants of a plurality of colors including black, the image processing method comprising: performing, by a first color conversion unit, first color conversion on first image data to output second image data, the first image data representing tone values of each of colors in a color system that differ from a color system of the plurality of colors for each of pixels that form the image, the second image data representing tone values of a black separation on a per-pixel basis; performing, by a second color conversion unit, second color conversion on the first image data to output third image data representing tone values of each of separations of the colors including black on a per-pixel basis; performing, by a first colorant reducing unit, a first colorant reducing process that reduces amounts of colorant to be consumed of black on the second image data to output fourth image data representing tone values of the black separation on a per-pixel basis; performing, by a second colorant reducing unit, a second colorant reducing process that reduces amounts of the colorants to be consumed of the colors other than black on a portion of the third image data, the portion corresponding to the separations of the colors other than black, to output fifth image data representing tone values of each of the separations of the colors other than black on a per-pixel basis; and combining, by a combining unit, the fourth image data and the fifth image data to output sixth image data representing tone values of each of the separations of the colors including black on a per-pixel basis.