A panoramic imaging apparatus functionally includes an image processing apparatus. In this apparatus, two planar images are produced, which are subjected to registration. A registration process is applied to overall areas of two planar images based on curves decided from positions designated on the two planar images respectively. The positions on each of the planar images are aligned along a straight line, both straight lines corresponding to each other in a horizontal direction, and a scale factor for the registration is changed position by position on the straight lines. One of the two planar images is searched for a match of each local region of the other planar image, to any of regions of the one planar image, and images of the matched regions are re-produced to produce a planar image. The difference information is calculated between the planar images.
