Patent ID: 8705122

Claim:
An image processing apparatus comprising: an output control unit configured to allow a printer to output chart data of a plurality of kinds of color mixture expressed by a three-dimensional color space constructed by cyan, magenta, and yellow (CMY); an obtaining unit configured to obtain colorimetry values obtained from the output chart data; a value forming unit configured to form a reference value by converting patch data of the color mixture expressed by the three-dimensional color space into a device independent color space on the basis of a first color conversion table for converting the three-dimensional color space into the device independent color space; a data correction unit configured to calculate differences between the colorimetry values obtained by the obtaining unit and the reference value formed by the value forming unit, to extract, from the calculated differences, a difference whose distance to each lattice point data of the device independent color space in a second color conversion table for converting the device independent color space into the three-dimensional color space stays within a threshold, and to correct the lattice point data on the basis of the extracted difference; a table correction unit configured to correct the second color conversion table by calculating values of the three-dimensional color space by using the lattice point data corrected by the data correction unit; and a table forming unit configured to form a color conversion table for correcting a four-dimensional color space constructed by cyan, magenta, yellow, and black (CMYK) by using the first color conversion table and the second color conversion table.