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:
Feb. 10, 2004
Filed:
Dec. 05, 2000
Robert A. Ulichney, Stow, MA (US);
Compaq Computer Corporation, Houston, TX (US);
Abstract
A method for correcting the tone of an input image for display on a given output device includes the steps of generating a dither template having advantageously more threshold levels than color levels of the input image. A tone characteristic for the output device is determined by comparing actual output pixel values against expected image pixel values. The tone characteristic curve is scaled to correspond with the number of threshold values in the dither template, and is stored in a look-up table having a number of entries corresponding to the number of threshold values in the dither template. The dither template values are fed to the look-up table, which provides an adjusted dither template which reflects the tone correction required to provide an output image free of tone distortion. The adjusted dither template is then normalized in accordance with characteristics of the input and output display devices. Elements of the normalized dither template are compared against incoming image pixels to determine which input image pixels are to be displayed on the output device.