A printer driver comprising: a layout determining section that acquires data of a document page (logical page) and determines a layout of one or more printing pages (physical pages) by allocating a content of the logical page; a re-layout determining section that makes determination whether the determined layout includes an combinable pages or not, based on a ratio of a blank area in the physical page and based on presence/absence of continuity in the contents between the page and the immediately preceding physical page or based on an arrangement characteristic of a non-blank area in the physical page, when one logical page is allocated to plural physical pages; and a page combination control section that causes the layout determining section to determine a combined layout by re-allocating the combinable page and immediately preceding physical page to a single physical page based on the determination.