Color of a color image may be adjusted by a color adjustment apparatus, image display apparatus, and color adjustment method to enable easier distinction between objects shown in the image. A parameter defines a range of saturation to be adjusted within saturation before color adjustment and a range of change of the saturation after color adjustment compared to the saturation before color adjustment. The color adjustment apparatus calculates the saturation from an image signal, calculates the saturation after color adjustment according to the saturation before color adjustment such that the saturation in the range determined by the parameter increases/decreases by an amount determined by the parameter, and generates an image signal from the saturation after color change. By determining the parameter such that the saturation difference between prescribed colors is greater after color adjustment, the difference in color between a plurality of objects shown in the image is increased.

Color of a color image may be adjusted by a color adjustment apparatus, image display apparatus, and color adjustment method to enable easier distinction between objects shown in the image. A parameter defines a range of saturation to be adjusted within saturation before color adjustment and a range of change of the saturation after color adjustment compared to the saturation before color adjustment. The color adjustment apparatus calculates the saturation from an image signal, calculates the saturation after color adjustment according to the saturation before color adjustment such that the saturation in the range determined by the parameter increases/decreases by an amount determined by the parameter, and generates an image signal from the saturation after color change. By determining the parameter such that the saturation difference between prescribed colors is greater after color adjustment, the difference in color between a plurality of objects shown in the image is increased.

An image-forming device includes a Central Processing Unit (CPU) and a storage device, wherein the storage device stores a color-conversion program, and the CPU functions as a centroid acquisition unit, a color-conversion-information generation unit, and an output-image generation unit. The centroid acquisition unit acquires a centroid of a cluster of approximate colors in an input image. The color-conversion-information generation unit generates color-conversion information for converting the input image to an output image. The output-image generation unit converts color in the input image, and generates the output image. The color-conversion information is information for moving a color in the input image according to movement of the centroid when moving the centroid to a representative color in a specific range.

A non-transitory machine readable medium that has a computer program for adjusting color values of an image represented in a color space is described. The image includes a set of pixels. Each pixel includes a set of color values. The computer program displays a composite bump on a tonal adjustment graph that is defined along a particular color component of the color space. The composite bump is generated by blending several bumps on the tonal adjustment graph. In response to receiving an input on a location on the tonal adjustment graph, the computer program creates a new bump based on the input and blending the new bump with the composite bump to create a modified composite bump. The computer program adjusts the color values of the image based on the modified composite bump.

An apparatus includes, a change unit configured to change a pixel value of an edge pixel indicating an edge portion of an image based on the image data having the quantized color, wherein, in a case where the pixel value of the edge pixel is a pixel value changed by color reduction processing to decrease a luminance, the change unit changes the pixel value of the edge pixel to a pixel value of a pixel having a highest luminance among pixels surrounding the edge pixel, and wherein, in a case where the pixel value of the edge pixel is a pixel value changed by the color reduction processing to increase a luminance, the change unit changes the pixel value of the edge pixel to a pixel value of a pixel having a lowest luminance among pixels surrounding the edge pixel.

An apparatus includes, a change unit configured to change a pixel value of an edge pixel indicating an edge portion of an image based on the image data having the quantized color, wherein, in a case where the pixel value of the edge pixel is a pixel value changed by color reduction processing to decrease a luminance, the change unit changes the pixel value of the edge pixel to a pixel value of a pixel having a highest luminance among pixels surrounding the edge pixel, and wherein, in a case where the pixel value of the edge pixel is a pixel value changed by the color reduction processing to increase a luminance, the change unit changes the pixel value of the edge pixel to a pixel value of a pixel having a lowest luminance among pixels surrounding the edge pixel.

An image processing apparatus generates image data used in printing an image on a sheet being attachable to skin. The image processing apparatus includes: an image acquirer that acquires a skin image picked up from the skin; an image analyzer that extracts, from the skin image, a discolored region differing in color from surrounding skin by at least a predetermined level, and surrounding color being color of the skin surrounding the discolored region; a grouping processor that groups a plurality of the discolored regions, and determines an inclusive region for each region group which is a cluster of the grouped plurality of discolored regions or one discolored region not having been grouped, to include the one or a plurality of the region groups; and a printing controller that generates image data having a content of printing a pigment material that causes color of the inclusive region to approximate the surrounding color, on a region corresponding to the inclusive region in the sheet.

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for generating, based on a portrait image, a foreground image mask to indicate foreground pixels of the portrait image; identifying a percentage of white or near white pixels in the foreground by using the foreground image mask and pixel colors in the portrait image; determining whether the percentage of white or near white pixels in the foreground is larger than a predefined threshold; in response to determining, triggering identification of edge pixels in a background of the portrait image; adjusting white background pixels to add shadows by darkening the white background pixels; and adjusting the white or near white pixels in the foreground by darkening the white or near white pixels.

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for generating, based on a portrait image, a foreground image mask to indicate foreground pixels of the portrait image; identifying a percentage of white or near white pixels in the foreground by using the foreground image mask and pixel colors in the portrait image; determining whether the percentage of white or near white pixels in the foreground is larger than a predefined threshold; in response to determining, triggering identification of edge pixels in a background of the portrait image; adjusting white background pixels to add shadows by darkening the white background pixels; and adjusting the white or near white pixels in the foreground by darkening the white or near white pixels.

An information processing apparatus includes: an object aggregating unit configured to aggregate spot color objects that are object to be printed in respective spot colors, for each of types of the spot color objects based on drawing information indicating the spot colors or methods of printing in the spot colors, to place the spot color objects on spot color layers corresponding to the types.