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. 18, 2008
Filed:
Feb. 18, 2003
David E. Rumph, Pasadena, CA (US);
Charles M. Hains, Altadena, CA (US);
David E. Rumph, Pasadena, CA (US);
Charles M. Hains, Altadena, CA (US);
Xerox Corporation, Norwalk, CT (US);
Abstract
A method for color cast removal in a scanned image in L*a*b* space includes generating a first color cast correction curve for mapping L* to a first color correction, Δa*, (or Δb*) wherein the first correction curve provides a desired a* shift in midtone regions and is modulated as a function of L* such that black and white points are unaffected; for each pixel n in the scanned image, passing L*through the first color cast correction curve for obtaining a value of Δa*; and adding the value of Δa*to the scanned image's original a*component. To ensure that the color corrected a* remains within gamut, a second correction curve for applying a clipping factor to the mapped Δa* may be generated with the a*passing through the second correction curve for obtaining a clipping factor C; and modifying the a*value by C(Δa*).