A color expression conversion apparatus includes a color expression conversion rule storage unit that stores a rule for converting a textual expression of a specific color into another textual expression, and a color expression conversion control unit that converts a textual expression of a color included in document data into another textual expression in accordance with the rule.

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.

In some examples, a system detects a highlighted area in an image content, the highlighted area including a portion of the image content, and a highlighting mark that highlights the portion of the image content. The system applies a color adjustment process in the highlighted area, wherein the color adjustment process comprises adjusting a color of the highlighted area comprising the portion of the image content highlighted by the highlighting mark, and wherein the adjusting of the color of the highlighted area comprises adjusting color values of plural color components in a first color space.

An image reading apparatus includes a first roller including a first rotation shaft and a first roller portion, an image reading unit, a first guide portion, a second guide portion arranged downstream of the first roller in a sheet conveyance direction, the second guide portion being curved with respect to a direction orthogonal to an axial direction of a first rotation shaft and the sheet conveyance direction, and a second roller. A reading position is located in a region between a first straight line and a second straight line, the first straight line passing through a first end, in the axial direction, of the first roller portion and extending in the sheet conveyance direction, the second straight line passing through a second end, in the axial direction, of the first roller portion and extending in the sheet conveyance direction.

In a document represented by CMYK process colors, a color that a user wishes to remove is prevented from remaining without being removed by specified color removal, and even a color that the user does not wish to remove by rights is prevented from being removed.

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.

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.

In some examples, a system detects a highlighted area in an image content. The system applies a color adjustment process in the highlighted area. The color adjustment process is not applied in areas of the image content outside the highlighted area, and the color adjustment process includes an operation of adjusting a color of the highlighted area. The adjusting of the colors of the highlighted area includes adjusting a color value of a specified color space.

Certain examples described herein relate to halftone level adjustment for Neugebauer Primaries (NPs). In certain examples, halftone levels for NPs are obtained for a halftone for printing an image. It is determined whether the halftone corresponds to a line or an area fill. The halftone levels may be adjusted in response to these levels exceeding a printing attribute threshold. The printing attribute threshold may be dependent on whether the halftone corresponds to a line or an area fill. The image may then be printed using the adjusted halftone levels.

Methods, systems and computer readable media for color management are described. In some implementations, the method can include accessing one or more buildup curves associated with a combination of a substrate, one or more colorants and a colorant dispenser. The method can also include accessing a design file specifying a design and including one or more layer files each specifying a layer color. The method can further include generating, for each layer color, a corresponding colorization recipe based on the one or more buildup curves. The method can also include creating a production job instruction/metadata file having a link to the design instruction/metadata file and including parameters associated with the colorant dispensing job to be carried out using the design instruction/metadata file.