1. An image processing apparatus that performs a type of image processing selected from a plurality of types of image processing, on an image, comprising: a display device that displays the image; a designating device that designates a predetermined position on the displayed image; a first acquiring device that acquires information on the designated predetermined position; a selecting device that selects a type of image processing to be performed on the displayed image from among the plurality of types of image processing; a second acquiring device that acquires information on the selected type of image processing; a defining device that defines a predetermined processing area on the displayed image, in which the displayed image is to be subjected to the selected type of image processing, according to the acquired information on the predetermined position and the acquired information on the selected type of image processing; and a display changing device that changes display of the image in the defined processing area.