In some implementations, a method includes: obtaining a first image; determining characterization properties for each of a plurality of pixels within the first image; determining a dominant hue based on the one or more characterization properties for each of the plurality of pixels within the first image; determining a plurality of hues that satisfy a predetermined perception threshold relative to the dominant hue based on the characterization properties for each of the plurality of pixels within the first image, wherein the plurality of hues is different from the dominant hue; and generating a second image based at least in part on the dominant hue and the plurality of hues. In some implementations, the second image corresponds to a color gradient generated based on the dominant hue within the first image. In some implementations, the second image is set as a wallpaper for a user interface.

An image processing method includes a first conversion step, a second conversion step that, using a second conversion table for converting input image data represented by a second color space to output image data represented by the second color space, converts image data of a second region for which recording conditions are different from a first region in a second image data, and a recording data generating step that generates recording data based on third image data including image data of a first region in the second image data and image data of the second region after conversion using the second conversion table. When adjusting an ink amount, the ink amount is not adjusted in the second conversion step and is adjusted in the first conversion step.

A method of color mapping color values of an oligochromatic pattern comprising the following steps: determining an image-gamut, in a N-dimensional device independent color system (ND-DICS), of said oligochromatic pattern; wherein said image-gamut comprises said color values of said oligochromatic pattern; and determining a skeleton (500) of said image-gamut; and performing an adaption on said skeleton (500) in said ND-DICS by a set of N-dimensional-transforming steps (30) and determining for points of said skeleton (500), a path in said ND-DICS that corresponds to said adaption; and color mapping said color values, of said oligochromatic pattern, based on said determined paths (35) of said points of said skeleton (500).

The present disclosure relates to a color gamut mapping method and a color gamut mapping device. A color gamut mapping method may include converting, by a color space converter, first three-color signals into a first luminance component and a pair of first chrominance components and outputting the first luminance component and the pair of first chrominance components, controlling, by a saturation controller, a saturation of the first chrominance component for each control area using a saturation gain of the saturation controller and outputting a second chrominance component, controlling, by a hue controller, a hue of the second chrominance component for each control area and outputting a third chrominance component, interpolating, by an overall controller, a set value of a luminance gain using grayscale differences between the first three-color signals, outputting a second luminance component by controlling first luminance component using the interpolated luminance gain.

An image forming apparatus includes: a scanner to read each of a first output product serving as a model and a second output product output from the image forming apparatus; a memory that stores a color conversion lookup table to be used when color conversion is performed from a RGB color system into a CMYK color system; and circuitry to correct the color conversion lookup table based on a number of pixels and an amount of change per hue, using read information on the first output product, and re-correct the corrected color conversion lookup table, using read information on the second output product.

Systems and methods are disclosed for non-linear color correction. The method including receiving an input image from an image sensor, converting the input image from a red, green, blue (RGB) color space format to an alternate color space format, determining localized hue correction parameters for a selected color in the alternate color space, determining localized saturation correction parameters for a selected hue in the alternate color space, applying the localized hue correction parameters and the localized saturation correction parameters to the input image to generate an output image and storing, displaying, or transmitting the output image based on at least the localized hue correction parameters and the localized saturation correction parameters.

The present principles relate to a method and device for gamut mapping from a first color gamut towards a second color gamut. The method comprises obtaining a preserved key color (prsv_color.sub.K0) and a hue alignment angle (θ.sub.K0) of the key color (color.sub.K0) for each key color (color.sub.K0) of at least 3 key colors to define a preserved gamut and a rotated gamut; and performing a hue mapping of a current color (color) from the first color gamut towards the second color gamut wherein in case the current color (color) is in a preserved gamut defined by the preserved key color (prsv_color.sub.K0), the hue mapped current color is unchanged, and in case the current color is out of the preserved gamut, the hue mapped current color is calculated from the hue alignment angle (θ.sub.K0) of two adjacent key colors of the current color (rotated gamut) and from the preserved area.

Provided is an image processing method for generating print data, the method including an ink amount generating step for generating CMYK data based on image data. The ink amount generating step determines the CMYK data based on a brightness L* calculated using a function f3(D) satisfying f1(D)≥f3(D) in a range of the gradation values D from a coordinates Pk to a coordinates Ps and also satisfying f1(D)≥f3(D) in at least part of the range.

There is provided a color gamut mapping device capable of fine adjustment configured to map a color signal to a predetermined color gamut by changing the saturation, hue, and luminance of the corresponding color signal, the color gamut mapping device including a hue angle calculation unit configured to calculate a hue angle using saturation components (Cb, Cr) of a YCbCr-type color signal (Y, Cb, Cr); a parameter generation unit configured to generate at least one of a saturation parameter, a luminance parameter, and a hue parameter using the hue angle; and a color signal changing unit configured to change the YCbCr-type color signal (Y, Cb, Cr) to be mapped to a predetermined color gamut using the parameter, wherein the color signal changing unit includes a saturation changing unit configured to calculate a saturation boundary value determined as a boundary of a predetermined rectangle on a Cb-Cr coordinate plane.

An image reading apparatus configured to read an image of an original, the image reading apparatus includes an original tray on which the original is to be placed; a pickup roller configured to feed the original placed on the original tray to a conveyance path; a first conveyance roller configured to convey the original which is fed to the conveyance path by the pickup roller; a second conveyance roller, which is located downstream of the first conveyance roller in a conveying direction in which the original is conveyed, configured to convey the original which is conveyed by the first conveyance roller; and a reading unit configured to read, at a reading position, an image of the original being conveyed by the first conveyance roller, the reading position being a position located downstream of the second conveyance roller in the conveying direction.