To effectively expand a color reproduction range in the case of using color material for a specific color in color separation data generation.

If saturation is higher in the entire lightness range when ink for a specific color is used at the side of high lightness than maximum saturation in the hue of a specific color (S404), a color separation data table is prepared in which only the ink for a specific color is used (S405). Meanwhile, in a lightness range (S404) in which saturation is higher when a combination (color mixture) for reproducing hue among four basic colors is used to prepare gradation colors than when only ink for specific colors is used in the range of lightness higher than maximum saturation of respective hue of ink for specific colors to prepare gradation colors or in a lightness range in which saturation is lower, a color separation table is prepared in which a combination (color mixture) of basic four colors for reproducing the same hue as the ink of specific colors is used for the ink for specific colors (S406).