To attain good color reproducibility for a reference color of a print image.

A printer 20 is controlled to acquire ID (error information) 31a representative of comparison results of reference colorimetric data and colorimetric data obtained by subjecting a color correction patch (standard image) P3 printed onto a print sheet (print medium) with a standard dot recording rate (ink recording amount) to colorimetry in an Lab color space (predetermined color space), to correct it into dot quantity data for compensating the color gap of an image being printed from dot quantity data (print data) representative of an image by means of the printer 20, and to print an image corresponding to the corrected dot quantity data by means of the printer 20.