Method and apparatus for adaptively thresholding grayscale image data
CA 2108797 C · Owner: Klein, Robert Dennis · Inventors: Klein, Robert Dennis; Kidd, Robert Charles
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method and apparatus for adaptively adjusting (e.g. thresholding) grayscale image data associates with each document image file (210, 212) a predetermined grayscale adjusting function (216) which can be used to threshold, contrast stretch and gray level reduce the original gray level image of the document into a picture representation for display at workstations the picture re-, presentation yielding increased contrast of written and printed text viewed. The invention includes a method of generating a remapping function for use in converting near-photographic document image pixel gray level data lying in a first range of gray level values to higher contrast, background-suppressed pixel …
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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 April 24, 1992 and granted March 11, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 24, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 24, 2014.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.