1. An image processing device comprising: a CPU which is configured to operate as: an acquiring section which acquires a plurality of panoramic images, each of which is generated by combining a plurality of images captured while an image capturing section is being moved along a first direction, wherein a length in the first direction of each of the plurality of panoramic images is longer than a length in a second direction of each of the plurality of panoramic images, and wherein the first direction is substantially perpendicular to the second direction; a comparing section which compares the lengths in the first direction between the plurality of panoramic images; and a wide-range image generating section which generates a wide-range image by combining the plurality of panoramic images such that the plurality of panoramic images are set along the second direction, wherein a length in the first direction of the wide-range image is substantially equal to one of the lengths of the plurality of panoramic images in the first direction which is determined to be shorter than others of the lengths of the plurality of panoramic images in the first direction based on a result of the comparison by the comparing section.