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:
Jun. 05, 1990
Filed:
Sep. 27, 1989
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An image forming apparatus for forming an image of a partial area of an entire image frame includes an apparatus for designating a part of a frame and apparatus for selecting an image formation operation for the predetermined area designated by the designating means or an image formation operation for the entire area. The image data corresponding to the predetermined area is read out and a histogram, indicating intensity distribution, is produced corresponding thereto. A gamma conversion characteristic is determined based on a cumulative frequency distribution produced from the histogram. The image data read out is converted in accordance with the determined gamma conversion characteristic. An image is formed on the basis of the converted image data representing the predetermined part of the frame or the entire frame. In such a partial printing, the contrast or gamma characteristic of the partial image may be appropriately corrected by a correction of the gamma characteristic according to the selection of the partial area.