In the related art, it was difficult to compare lengths of a plurality of objects which were present at different places. However, it is possible to easily compare lengths of photographed objects using an image capturing device which displays a length of an object which is calculated based on parallax information, by obtaining an image in which the object is photographed and the parallax information corresponding to the image as inputs, the device including an object extraction unit which extracts an image of an object using the parallax information from the photographed image; a comparison data maintaining unit which maintains the image of the object and the length of the object; an object comparison unit which compares the length of the object which is extracted using the object extraction unit to a length of comparison data which is extracted from the comparison data maintaining unit; and an image composition unit which combines a comparison result with the photographed image, and outputs the image.