1. An image processing apparatus comprising: a display unit to display image data; a range specifying unit to specify a range corresponding to the image data; a characteristic extracting unit to extract a representative characteristic from image data within specified range among the image data; a storing unit to store extracted representative characteristic associated with the image data; and a display controlling unit to control to display the representative characteristic associated with the image data when retrieving the image data for displaying the image data on the display unit.