1. An image processing apparatus for arranging rectangular images in a circular area usable for layout of the images, comprising: a number-of-images selection unit that selects a number of images to be subjected to layout arrangement a parameter setting unit adapter to set a parameter for a layout condition to arrange a plurality of images in a spiral pattern on a recording medium when the recording medium is provided as a circular recording medium to be subjected to layout of the plurality of images; and a shape changing unit adapted to change the shape of the rectangular images in accordance with the parameter set by said parameter setting unit, wherein said parameter setting unit determines the number of turns of the spiral pattern in accordance with the number of images to be subjected to layout and sets the parameter to change the shape of the rectangular images so as to be fitted to an area surrounded by the spiral pattern and two adjacent straight lines respectively passing through the center of the circular recording medium, and wherein the image processing apparatus is arranged to switch between an original image and a thumbnail image in accordance with the size of the image subjected to the shape changing by said shape changing unit, to selectively use the original image and the thumbnail image as the image the shape of which is changed by said shape changing unit so as to be fitted to the area.