To properly complete a printing process without suspending it in the middle of one page even when using a memory having capacity insufficient to store image data corresponding to one page in a printer.

In a host computer 101 communicable with the printer 102 performing the printing process on the basis of the image data of a plurality of colors, a printer driver generates the image data printed by the printer 102 by prescribed generation processing, divides the generated image data corresponding to one page into each the color, compresses the divided division image data, decides whether a data amount of the compressed division image data is more than a prescribed data amount or not, and transfers the compressed division image data to the printer 102 while controlling processing conditions of the prescribed generation processing such that the conditions are different.