Exterior orientation parameters of a camera are easily determined by, for example, a reference image being obtained by photographing a building 131 with a camera 112, in which exterior orientation parameters are determined, while a vehicle 100 travels, and a comparative image being simultaneously obtained by photographing the building 131 with a camera 113, in which exterior orientation parameters are undetermined. Then, points that match between the reference image and the comparative image are selected, and relative orientation and scale adjustment using a predetermined scale are performed, whereby the exterior orientation parameters of the camera 113 are calculated.