An image processing apparatus comprising: a first color conversion table adapted to convert a device-independent color space into a uniform color space, the uniform color space being a color space in which Lab color space is corrected to improve correlativity with human visual characteristics; an output means configured to output a chart to a printer by using a plurality of types of multi-color chart data represented in a three-dimensional color space formed of cyan, magenta, and yellow; a colorimetric value acquisition means configured to acquire colorimetric values resulting from colorimetry performed on the output chart in the device-independent color space; a color conversion table acquisition means configured to acquire a second color conversion table adapted to convert the three-dimensional color space into the uniform color space; a conversion means configured to convert the acquired colorimetric values of the device-independent color space into acquired colorimetric values of the uniform color space by using the first color conversion table which is adapted to convert the device-independent color space into the uniform color space; a target value acquisition means configured to acquire predetermined target values of the uniform color space; a correction means configured to correct a pre-stored third color conversion table, which third color conversion table is adapted to convert the uniform color space into the three-dimensional color space, by using differences between the acquired colorimetric values of the uniform color space and the acquired target values of the uniform color space; a generation means configured to generate, using the second color conversion table and the corrected third color conversion table, a fourth color conversion table (812, 1013, 1212) adapted for use in multicolor correction processing by correcting a four-dimensional color space formed of cyan, magenta, yellow, and black; and multicolor correction processing means configured to perform multicolor correction processing based on the fourth color conversion table (812, 1013, 1212) to convert a combination of cyan, magenta, yellow and black signal values corresponding to respective toner values of an image to output cyan, magenta, yellow and black signal values. a first color conversion table adapted to convert a device-independent color space into a uniform color space, the uniform color space being a color space in which Lab color space is corrected to improve correlativity with human visual characteristics; an output means configured to output a chart to a printer by using a plurality of types of multi-color chart data represented in a three-dimensional color space formed of cyan, magenta, and yellow; a colorimetric value acquisition means configured to acquire colorimetric values resulting from colorimetry performed on the output chart in the device-independent color space; a color conversion table acquisition means configured to acquire a second color conversion table adapted to convert the three-dimensional color space into the uniform color space; a conversion means configured to convert the acquired colorimetric values of the device-independent color space into acquired colorimetric values of the uniform color space by using the first color conversion table which is adapted to convert the device-independent color space into the uniform color space; a target value acquisition means configured to acquire predetermined target values of the uniform color space; a correction means configured to correct a pre-stored third color conversion table, which third color conversion table is adapted to convert the uniform color space into the three-dimensional color space, by using differences between the acquired colorimetric values of the uniform color space and the acquired target values of the uniform color space; a generation means configured to generate, using the second color conversion table and the corrected third color conversion table, a fourth color conversion table (812, 1013, 1212) adapted for use in multicolor correction processing by correcting a four-dimensional color space formed of cyan, magenta, yellow, and black; and