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. 28, 2015
Filed:
Nov. 27, 2013
Mcgraw-hill School Education Holdings Llc, New York, NY (US);
The Board of Trustees of Southern Illinois University, Carbondale, IL (US);
Raghuveer Kanneganti, Carbondale, IL (US);
Randal B. Fry, Salinas, CA (US);
Lalit Gupta, Carbondale, IL (US);
Ahmed Freidoon Fadhil, Carbondale, IL (US);
McGraw-Hill School Education Holdings LLC, New York, NY (US);
The Board of Trustees of Southern Illinois University, Carbondale, IL (US);
Abstract
A method, system, and algorithm detects graphite responses in optical mark recognition documents using inexpensive visible-light scanners. The invention is invariant to the numerous background colors and artwork in typical optical mark recognition documents. A superposition of a graphite response image and a background image is modeled. The background image in turn is modeled as a superposition of screening, artwork, lines, and machine text components. A sequence of image processing operations and a pattern recognition algorithm is used to isolate the graphite response image from a test document by systematically removing the components of the background image. The image processing operations consist of grayscale and color segmentation and the application of the Hough transform. Components that are not removed by image processing operations are identified by calculating their texture features, and removed using a multivariate Gaussian classifier.