Patent ID: 7542834

Claim:
A computer-implemented method of obtaining a motion of a mobile body on which a camera is mounted, using images of a surrounding of the mobile body captured by the camera, comprising: a corresponding point calculation step of obtaining a plurality of corresponding points from two of the images having different capturing times; a first motion calculation step of obtaining a first motion indicating the motion of the mobile body using the plurality of corresponding points, assuming a predetermined plane in the images; and a second motion calculation step of obtaining a second motion indicating the motion of the mobile body using the first motion and the plurality of corresponding points, wherein the first motion calculation step comprises: a first step of selecting q (where q is an integer of two or more) partial corresponding point sets each composed of m (where m is an integer of 3 or more) corresponding points from the plurality of corresponding points; a second step of calculating a candidate for the motion of the mobile body from each of the q partial corresponding point sets selected in the first step with a plane expression defining the plane; and a third step of evaluating the q motion candidates caculated in the second step with a predetermined evaluation technique, and based on a result of the evaluation, specifying the first motion.