Method and apparatus for halftone rendering of a gray scale image using a blue noise mask
CA 2231820 C · Owner: Mitsa, Theophano · Inventors: Parker, Kevin J.; Mitsa, Theophano
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of and system for rendering a halftone image of a gray scale image (500) by utilizing a pixel-by-pixel comparison (402) of the gray scale image against a blue noise mask (502) is disclosed in which the gray scale image is scanned on a pixel-by-pixel basis and compared on a pixel-by-pixel basis to an array of corresponding data points contained in a blue noise mask stored in a PROM (406) or computer memory in order to produce the desired halftoned image. Both digital and optically implemented halftone methods are disclosed. Application specific modifications of the blue noise mask as well as its use for producing halftoned color images are also disclosed.
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed December 3, 1991 and granted February 4, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 3, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 3, 2013.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.