PROBLEM TO BE SOLVED: To generate a high quality image of a target cross section by positioning tomographic image groups.SOLUTION: An object tomographic image group acquisition part 110 acquires a tomographic image group composed of a plurality of tomographic images, and a target cross section setting part 130 sets a target cross section. A positioning part 140 calculates a positioning parameter of respective tomographic images to perform positioning on the basis of a positional relation between the tomographic image group and the cross section. the tomographic image generation part 150 positions the tomographic image groups by using the positioning parameter of the respective tomographic images to generate an image of the target cross section.
