An image processing apparatus includes: a display control section that causes a display device to display an image indicating a state in which a figure indicating a color gamut, a dot indicating a designated color, and one or more axes each indicating a feature amount of a color are viewed in an identical three-dimensional color space from a predetermined viewpoint; and a receiving section that receives an instruction issued by a user. The display control section changes, in accordance with the instruction, the image upon changing the viewpoint.

A control apparatus capable of setting a suitable correction parameter while reducing user's troublesome. The control apparatus including a database that holds correction parameters for correcting pickup images to reduce color difference between pickup images of image pickup apparatuses in association with combinations of standard image pickup apparatus information and image pickup conditions of image pickup apparatuses, a memory device that stores instructions, and a processor that executes the instructions to obtain first information showing a standard image pickup apparatus at a present time and second information showing a target image pickup apparatus that picks up an image as a correction target at the present time, obtain the image pickup conditions of the image pickup apparatuses, determine a setting correction parameter that is set to the target image pickup apparatus from the database based on the first information and the image pickup conditions apparatuses, and output the setting correction parameter.

An image processing apparatus includes a controller configured to perform: setting characteristic information including first characteristic information and second characteristic information; and converting a target image data using the characteristic information. The first and second characteristic information correlate input values with output values in a specific color space. The input values includes a specific input value within a specific range. The specific input value is correlated with a first specific output value by the first characteristic information, and is correlated with a second specific output value by the second characteristic information. The first specific output value indicates that a colorant consumption quantity for the specific input value is changed from an original colorant consumption quantity by a first colorant quantity. The second specific output value indicates that the colorant consumption quantity is changed from the original colorant consumption quantity by a second colorant quantity different from the first colorant quantity.

A color conversion apparatus includes an independent color value converting circuit and a display color value converting circuit. The independent color value converting circuit converts the image color value into an independent color value independent from a device. The display color value converting circuit converts the independent color value converted by the independent color value converting circuit into the display color value. The independent color value converting circuit converts the image color value into the independent color value indicative of the print color by the print device corresponding to the print color value converted from the image color value. The display color value converting circuit converts the independent color value into the display color value based on display-device-property information indicative of a correspondence relationship between the display color value and the independent color value indicative of the display color by the display device corresponding to the display color value.

A printing system is disclosed. The printing system includes a color management unit having a hash table to store input colors and corresponding output colors and a lookup table (LUT). The printing system also includes one or more processors to reinitialize the hash table based on a hash table time and a interpolation time derived from concurrent real time measurements.

In a case where a sample color is outside a color reproduction range of an image forming apparatus, there arises an issue that an adjustment target color cannot be brought close to a user-desired color. An image forming apparatus includes a generation unit configured to cause a printing unit to print a plurality of colors close to an acquired sample color and generate a color conversion table based on a user-selected color among the plurality of printed colors in a case where it is determined that the acquired sample color is outside a color reproduction range of the image forming apparatus, whereas in a case where it is determined that the acquired sample color is not outside the color reproduction range, the generation unit generates a color conversion table without causing the printing unit to print the plurality of colors close to the sample color.

An image processing apparatus includes circuitry that estimates a first geometric transformation parameter for aligning first output image data with the original image data, the first output image data being acquired by reading a first output result, and a second geometric transformation parameter for aligning second output image data with the original image data, the second output image data being acquired by reading a second output result; associates, based on the first and the second geometric transformation parameters, combinations of color components of the first and the second output image data, corresponding to pixels of the original image data, to generate pixel value association data; determines, based on the pixel value association data, a mapping for estimating color drift between the first output image data and the second output image data from the original image data; and subjects the original image data to color conversion based on the mapping.

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).

An image processing apparatus includes a first adjustment unit for adjusting a color conversion table, used for converting a color to be printed by a printer, by adjusting a selected adjustment color using the selected adjustment color and a target color, a storage unit for storing, in a storage apparatus, a first color conversion table generated by causing the first adjustment unit to adjust the color conversion table for a first adjustment color and a second color conversion table generated by the first adjustment unit to adjust a second adjustment color different from the first adjustment color after generation of the first color conversion table, a cancellation unit for deleting an adjustment result of the first adjustment color, and a second adjustment unit for adjusting the second color conversion table in response to the deletion of the adjustment result of the first adjustment color.

Provided are a non-transitory computer-readable storage medium storing a control program for creating a database for use in color calibration and that storing a control program for a judgement based on the database. The control programs cause a computing device to perform the following operations. The database-creating operations include calculating a white-ground color difference using a print medium, and repeating a feedback adjustment of a color correction LUT, to obtain a resulting color accuracy. The operations further include obtaining white-ground color differences and resulting color accuracies for plural paper products of a certain print medium type, to obtain a mathematical relation and create a database. The judgement operations include using the database to calculate an estimated resulting color accuracy from a white-ground color difference calculated using a print medium, and judging whether to perform a feedback adjustment of a color correction LUT based on the estimated resulting color accuracy.