Stochastic halftoning screening method
CA 2203448 C · Owner: Xerox Corporation · Inventors: Wang, Shen-Ge
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An idealized stochastic screen is characterized by all of the predominant color dots (black or white) uniformly distributed. The present invention seeks to approach this optimization by iteratively selecting pairs of threshold levels in the screen matrix and measuring the approach to the idealized stochastic screen. The threshold values are then swapped in position to determine whether the swap improves the measurement or not. If it does the swap is maintained. The process is iterated until the desired result is obtained.
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 April 23, 1997 and granted November 28, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 23, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 23, 2019.
- 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.