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:
Nov. 13, 2012
Filed:
Jul. 29, 2009
Masahiro Kawashima, Ibaraki-ken, JP;
Masahiro Kawashima, Ibaraki-ken, JP;
Riso Kagaku Corporation, Tokyo, JP;
Abstract
A histogram preparer reads image data scanned from an original sheet by the line, preparing a histogram of pixel numbers of respective background densities of a read line, a background density estimator estimates a background density of the read line as a density at a local maximal value in view of a highlight end of the histogram, a background removal reference value setter sets up a background removal reference value as a reference margin based on a pixel number normalized on the estimated background density, a background removal threshold determiner increments the estimated background density by the background removal reference value to set a provisional background removal threshold of the read line, and determines a background removal threshold of the read line as a weighting combination of the provisional background removal threshold and a background removal threshold of a previous line, and a background remover removes a background of the read line based on the determined background removal threshold.