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:
Mar. 25, 2003
Filed:
Jun. 05, 1998
Applicant:
Inventors:
Yasuko Shibahara, Inagi, JP;
Atsushi Shoji, Kawasaki, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04N 1/46 ;
U.S. Cl.
CPC ...
H04N 1/46 ;
Abstract
In order to detect a forgery of a document formed from an input image, additional information is added to the input image using general image processing without including a specific information adding section in a general image processing unit. M-value image data is input and converted to N-value image data, wherein the value M is larger than the value N, on the basis of threshold table groups composed of plural kinds of threshold tables whose using order is determined so as to indicate the predetermined additional information which is embedded in the image, and is used for detecting the forgery.