1. A display processing apparatus comprising: a first display controller that displays a background image in a display unit; and a second display controller that displays a print image in the display unit, wherein the second display controller changes a magnification of the print image so that the print image has a size obtained by changing a size of a recording medium on which the print image is to be printed on a scale of the background image displayed in the display unit, and superimposes and displays the print image on the background image.