1. An image processing apparatus comprising: a display; a retrieving unit that retrieves image data; a process display unit that displays on the display a plurality of candidate image processes to be performed on the image data; a process receiving unit that receives an instruction indicating a selected image process selected from among the plurality of candidate image processes; a process storing unit that stores the selected image process; a thumbnail display unit that displays a thumbnail image corresponding to the image data on the display; and a thumbnail designating unit that designates a thumbnail image, wherein the thumbnail display unit displays a processed thumbnail image that represents a result of the selected process performed on the image data corresponding to the designated thumbnail image.