Patent ID: 7787689
Filing Date: 2010-08-31
Classification: G06T

Abstract:
1. A location measuring device comprising: a feature point extracting section for extracting a plurality of feature points on a photographing object from each of successively photographed images in a plurality of frames obtained with an image obtaining means, a location of the image obtaining means relatively varying to a location of the photographing object with time; a feature point tracking section for searching each of the successively photographed images for points corresponding to the feature points and tracking the feature points; a first track determining section for applying robust estimation to residuals, each of the residuals being a residual of a coordinate calculated by using a set of projection parameters between one and another images on a basis of locational relationship between the feature points on the one and the another images from a process of the tracking or results of the tracking by the feature point tracking section and determining an estimated value of the projection parameters; a second track determining section for determining a residual between a coordinate of the corresponding point corresponding to each of the feature points and an estimated coordinate of the corresponding point by utilizing the estimated value of the projection parameters determined with the first track determining section, applying a threshold process, determining whether or not the each of feature points is incorrect corresponding point, and removing the incorrect corresponding point from the feature points; a template re-matching section for determining an estimated coordinate of the corresponding point by utilizing the estimated value of the projection parameters determined with the first track determining section, and carrying out template matching in a vicinity of the estimated coordinate to determine a coordinate of each of appropriate corresponding points, and a location measuring section for measuring a coordinate of the photographing object, or the location or a photographing posture of the image obtaining means on a basis of coordinates of the corresponding points other than the incorrect corresponding points determined with the second track determining section and on a basis of the coordinates of the appropriate corresponding points determined with the template re-matching section.