Patent ID: 8855373

Claim:
A similarity calculation device, comprising: a displacement vector estimation unit for estimating a displacement vector between a plurality of first local regions set in a first image, and a second local region which is most similar to each of the first local regions in a second image; a geometric transformation parameter estimation unit for estimating a geometric transformation parameter which geometrically transforms the first image into the second image based on a plurality of the displacement vectors; a displacement vector correction unit for subtracting displacement caused by the geometric transformation from the displacement vector and correcting the displacement vector based on the geometric transformation parameter; a scoring unit for scoring the displacement vector, which has been corrected by the displacement vector correction unit, in a two-dimensional space defined by elements of the respective displacement vectors; a peak detection unit for detecting a peak in the two-dimensional space in which the scoring has been performed; and a similarity calculation unit for calculating a similarity of the first image and the second image according to a size of the peak.