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:
Dec. 10, 1996
Filed:
Nov. 10, 1994
Eastman Kodak Company, Rochester, NY (US);
Abstract
A technique, specifically apparatus and an accompanying method, for accurately thresholding an image based on local image properties, specifically luminance variations, and particularly such a technique that uses multi-windowing for providing enhanced immunity to image noise and lessened boundary artifacts. Specifically, a localized intensity gradient, G(i,j), is determined for a pre-defined window (300) centered about each image pixel (i, j ) . Localized minimum and maximum pixel intensity measures, L.sub.min and L.sub.max, respectively, are also determined for another, though larger, window (330) centered about pixel (i,j). Also, a localized area gradient measure, GS(i,j), is determined as a sum of individual intensity gradients for a matrix of pixel positions (370) centered about pixel position (i,j). Each image pixel (i,j) is then classified as being an object pixel, i.e., black, or a background pixel, i.e., white, based upon its area gradient, GS (i,j), and associated L.sub.min and L.sub.max measures.