Thresholding technique for graphics images using histogram analysis
CA 1301308 C · Owner: International Business Machines Corporation · Inventors: Pennebaker, William Boone
Overview
Its claims, description and drawings are in the Canadian Patents Database.
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Abstract of the Disclosure A system is described for thresholding graphics images to reduce the information content for transmission and reproduction and which uses a particular image data thresholding technique that may be used to obtain display images with a number of intensity levels. Firstly, an histogram of the image to be encoded is generated and analyzed to determine essential parameters. In particular the, background color of the image is determined by summing the histogram elements to find the median of the distribution, that is, the point at which the half sum of total pixels is reached. The extrema of the histogram are calculated and the skew is determined from the position of …
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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
- Granted May 19, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 19, 2009.
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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.