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:
Jul. 27, 1993
Filed:
Feb. 21, 1991
Yoshinobu Mita, Kawasaki, JP;
Naoto Kawamura, Yokohama, JP;
Yuji Nishigaki, Tokyo, JP;
Katsuhito Dei, Tokyo, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
There are image processing method and apparatus for use in digital copying apparatuses, facsimile apparatuses, etc. which handle an image signal. This apparatus comprises an edge detector to detect the edge portion of the image signal, a smoothing circuit to smooth the image signal, an edge emphasizer to emphasize the edge of the image signal, and a mixer to mix the output of the smoothing circuit and the output of the edge emphasizer. A mixture ratio of the output of the smoothing circuit and the output of the edge emphasizer is varied in response to the output of the edge detector. The edge detection of the edge detector is performed due to the linear differentiation. With this apparatus, the moire in the case of a mesh original image is removed and the characters and line drawings can be reproduced with a high degree of fidelity.