Patent ID: 8260060

Claim:
A comparison method for comparing images by using registered information, including: a first step of designating a first registration information inherent to a first parameter obtained by processing a registered image based on a set first parameter, as said registration information used for said comparison; and a second step of, when receiving an instruction for change of said registration information after said designation in said first step, designating second registration information obtained by performing said processing of said registered image based on a second parameter different from said first parameter, as the registration information used for said comparison, wherein, in said first step, a generalized Hough transform processing is carried out to said registered image based on said set first parameter to generate said registration information, and in said first step, as the result of said generalized Hough transform, said registration information is generated, said registration information linking, at a picture element position on an image pattern in said registered image, first angle information indicating the angle formed by a straight line perpendicular to a tangent of said image pattern and a straight line passing through said picture element position and parallel to a reference axis, distance information indicating the distance between said picture element position and a set position indicating said set first parameter, and second angle information indicating the angle formed by a straight line including said picture element position and said set position and said reference axis.