1. A printer outputting a plurality of print data corresponding to am image to be printed on a same page, each of the print data having an attribute, said printer comprising: an image buffer storing each of the print data in accordance with the attribute; a plurality of video interfaces, each of said video interfaces reading each of said print data stored in the image buffer; a print data integration circuit integrating the plurality of print data read by the video interfaces into a piece of print data for the same page; and an output mechanism outputting the image of the same page based on the print data integrated by the print data integration circuit.