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. 06, 1993
Filed:
Feb. 12, 1992
Greg A Degi, Fort Collins, CO (US);
Graig L Miller, Boise, ID (US);
Irene F Stein, Fort Collins, CO (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
In a document scanner that is operating in the binary mode, the magnitude of the signal that is generated for each picture element (PEL) of each document scan line is compared to the magnitude of a threshold signal. Either a binary 0 or a binary 1 is generated as a result of this comparison. The threshold signal magnitude is dynamically established by a method and an apparatus that provides a stored history or histogram of the various signal magnitudes that are generated for each PEL of a plurality of the document scan lines. Since the signal magnitude(s) that is provided by scanning the background, non-image, area of the document occurs the majority of the time within this histogram, the magnitude of this majority signal(s) is used to set the threshold signal magnitude. As a result, the PELS of the document's visible image are converted to a binary electronic image with a minimum loss of visual image content. The threshold signal magnitude is continuously established in this manner during the scanning of a document.