The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 08, 1997
Filed:
Oct. 06, 1993
Tadao Iwaki, Tokyo, JP;
Nobuyuki Kasama, Tokyo, JP;
Shuhei Yamamoto, Tokyo, JP;
Toshiharu Takesue, Tokyo, JP;
Yasuhiro Takemura, Tokyo, JP;
Seiko Instruments Inc., , JP;
Sumitomo Cement Co. Ltd., , JP;
Abstract
An object of the invention is to provide a method and a apparatus for optical pattern recognition capable of accurately comparing and identifying a reference image accurately at a real-time even when the input image rotates or its size changes by being compared with a reference image that is a desirous target. The method and apparatus comprise the processes of; steps (6, 11) for independently obtaining a lower-frequency component and a higher-frequency component from a joint Fourier transform image 5 of the reference image 4 and the input image 3; steps (10, 15) for calculating correlation coefficients respectively from the lower-frequency component and the higher-frequency component; step (16) for obtaining a ratio of the respective correlation coefficients; and step (19) for identifying and comparing a correlation coefficient ratio of the two same reference images to be required with a correlation coefficient ratio obtained from step (16).