Image-processing apparatus
CA 1306540 C · Owner: Semasa, Takayoshi · Inventors: Ono, Fumitaka; Semasa, Takayoshi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An input gray-scale image is converted to a bilevel output signal by an image-processing apparatus with two binarizing circuits: one employing a uniform threshold and the other a dither matrix. The outputs of these circuits are selected for each pixel by deciding whether the pixel is a bilevel pixel or a gray-scale pixel. The decision is based on the maximum and minimum gray levels in a block of pixels centered on the pixel in question. Images having both bilevel and gray-scale parts can thus be binarized with clean reproduction of black-white edges.
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
- Granted August 18, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended August 18, 2009.
- 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.