According to the claimed invention, an image forming apparatus comprises an image forming unit which forms an image represented by data of a specific format; a reception unit which receives print data of each page containing object data representing each of a plurality of types of objects; a data rasterization unit which has object conversion units which convert the object data into data of the specific format; a composition unit which composites data of the specific format corresponding to the object data converted to page data of the specific format containing the object data; and a control unit which inputs the page data to a subsequent processing unit for each page to use the page data for image formation by the image forming unit, wherein the data rasterization unit converts object data into data of the specific format regardless of a break of each page containing the object data.