1. An image processing apparatus, which has multiple image processing functions, for processing an entered image using an image processing function that has been set at the time of image input, comprising: a designating unit adapted to designate a processing mode for using any of the plurality of image processing functions to be applied to an image of interest; an extracting unit adapted to extract an identification indicator representing setup information to be used when a print medium on which the image of interest has been printed is read and the image of interest processed using the plurality of image processing functions; an analyzing unit adapted to analyze the identification indicator and acquire the setup information; and a processing unit adapted to process the image of interest using setup information, among the setup information analyzed by said analyzing unit, to be used by an image processing function regarding a processing mode that has been designated by said designating unit when the print medium is read.