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. 09, 1993
Filed:
Dec. 03, 1990
Robert P Kowalski, Campbell, CA (US);
Dan S Bloomberg, Palo Alto, CA (US);
Xerox Corporation, Rochester, NY (US);
Abstract
A simple technique for determining and indicating, in real times as an image is scanned, the presence of halftones within a page. in brief, the technique contemplates monitoring a pixel stream, typically on a line basis, determining the proportion of pixel transitions (relative to the overall number of pixel intervals), and controlling the process based on this information. In one embodiment, a numerical value representing such a proportion is compared to a threshold, and a value in excess of the threshold is taken to signify the presence of halftone regions. Based on this, special processing for halftones is enabled or special processing for non-halftone regions is disabled. In a specific hardware embodiment, the pixel monitoring circuitry includes a transition detector (50), an up/down activity counter (52), a threshold selector (55), and a counter controller (57).