Error diffusion for color images with semi-vector quantization
CA 2272781 C · Owner: Harrington, Steven J. · Inventors: Fan, Zhigang; Harrington, Steven J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for color error diffusion using semi-vector quantization is proposed that simplifies error diffusion calculations. When three color separations are used, the two separations with the most visually perceptive color output are compared with one another to determine their output colors while the third, least visually perceptive separation is treated separately. , A, correction term may be applied to the third separation based on the color output of the first two separations to insure uniformity of ink coverage. This method yields results close to vector quantization and also minimizes fluctuation in the two most visually perceptive output colors. Of course this, method may be used …
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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 May 20, 1999 and granted February 26, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 20, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 20, 2021.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.