An image forming apparatus includes first and second interpreters configured to interpret page description language data and generate intermediate data. The apparatus further includes a setting unit configured to set an image quality priority mode for one of the first and second interpreters and a color/monochrome determination priority mode for the other of the first and second interpreters. Either the first interpreter or the second interpreter, for which the color/monochrome determination priority mode is set, skips the generation of the intermediate data for a processing target page in a case where it is determined that the processing target page is a color page.