Patent ID: 6873422
Filing Date: 2005-03-29
Classification: G01B

Abstract:
1. A method for estimating a displacement of a second image acquired by a sensing device relative to a first image acquired by the sensing device, the method comprising: determining a set of image-dependent correlation function value points indicative of a correlation function extremum, each image-dependent correlation function value point based at least partially on a pattern of image values included in both the first image and the second image, each image-dependent correlation function value point further based on a respective known spatial translation of the image values in the second image relative to the image values in the first image; and estimating at least one respective spatial translation position corresponding to at least one respective symmetry point based on a plurality of the image-dependent correlation function value points bounding the correlation function extremum, the at least one respective spatial translation position-indicative of the displacement of the second image relative to the first image. wherein estimating the spatial translation position corresponding to the at least one respective symmetry point comprises determining the midpoint of at least one line segment having a first endpoint that is one of