The invention provides an image processing apparatus, an image processing method, and a medium. The image processing apparatus comprises: an obtaining unit that obtains a luminance of an input image having a color reproduction range wider than that of a printing apparatus; a conversion unit that performs, for the input image, conversion processing of obtaining a value included in the color reproduction range of the printing apparatus and obtaining the luminance of the image after the conversion; and a correction unit that corrects the luminance of the input image, wherein the correction unit performs correction of the luminance of the input image based on a conversion characteristic between the luminance obtained by the obtaining unit and the luminance obtained by the conversion unit suchthat an intensity of the correction becomes higher for a color that is not included in the color reproduction range of the printing apparatus than for a color included in the color reproduction rangeof the printing apparatus.