Improved error diffusion system
CA 2112469 C · Owner: Bowers, Harry · Inventors: Bowers, Harry
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
For highlight or dark areas of images, the error terms (52) diffused to neighbourhood pixels includes components which are periodic with respect to a wavelength where the wavelength is a function of the density level of the pixels from which the error terms are diffused. In this manner, patterned artifacts or "worms" in the highlight or dark areas of the images are reduced or illuminated.
Read the whole patent
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 5, 1992 and granted February 27, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 5, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 5, 2014.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.