PROBLEM TO BE SOLVED: To generate a development image which correctly shows inner surfaces of a luminal organ even if endoscopic images are included which are captured with the optical axis of the endoscope deviated from the centerline of the lumen of the organ when a plurality of endoscopic images are used to generate the development image in a development image generation apparatus, method, and program, and image information storage device.SOLUTION: When a toric region is set in each of a plurality of endoscopic images and image parts of the set toric regions are combined to generate a development image, reference positions to set the toric regions in the endoscopic images are determined, using the directions and distances in and by which the photographing positions of the endoscopic images are away from the corresponding positions on the centerline of the lumen of the luminal organ. The toric regions are set in positions determined with the determined reference positions as the references and the image part of the toric region set in each of the plurality of endoscopic images is converted into a belt-shaped image, and then the converted images are arranged side by side to generate a development image.SELECTED DRAWING: Figure 5
