Defect-free printing is achieved by previewing on a display prior to printing, device functions and print specifications. Preview of double-sided faces is concurrently provided when double-sided printing is specified. A preview image is displayed indicating a first printing face on which a plurality of pages have been placed based on a layout attribute, a double-sided printing attribute and document data. The preview image is further modified based on whether or not specified pages of the document data have or have not been deleted.