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. 27, 2001
Filed:
Mar. 31, 1998
Ho Chong Lee, Endicott, NY (US);
Mikel J. Stanich, Longmont, CO (US);
Gerhard R. Thompson, Wappingers Falls, NY (US);
Jack L. Zable, Niwot, CO (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method of generating artifact-free threshold matrices for digital printing devices is provided. The method includes, for example, the steps of establishing a threshold matrix by examining at least one color level for artifacts and removing the color level from the threshold matrix if it has artifacts. The method further includes the steps of examining a range of color levels for artifacts and removing the color levels from the threshold matrix which have artifacts and evenly distributing the remaining color levels over a range of color levels from a first color level to a last color. The examination of color levels for artifacts may be implemented manually or through an automated computer controlled process. The automated process includes digitally acquiring the color level and performing a Fourier transform on the color level to determine its spectral components. The spectral components are analyzed to determine the presence or absence of artifacts. Color levels having artifacts may be removed from a threshold matrix via one of several removal procedures. Once the threshold matrix is defined by artifact-free color levels, it is then integrated or stored into a printer or display device.