Methods for performing 2-dimensional maximum differences coding and decoding during real-time facsimile image compression and apparatus therefor
CA 2206426 C · Owner: Dimolitsas, Spiros S. · Inventors: Dimolitsas, Spiros S.; Ragland, Roderick J.; Corcoran, Franklin L.
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Compression and decompression methods for transmitting facsimile images in which the facsimile image is compressed in both vertical and horizontal directions are implemented using two dimensional maximum differences algorithms. Asymmetrical and fractional image compression are provided by controlling the number of lines, i.e. rows or columns being compressed and , by controlling the bit segment length used during each differences determination. The compressed facsimile image is decompressed by selecting a reference bit in the decompressed facsimile image and expanding the bit in both vertical and horizontal directions in accordance with a binary value of bits near the selected …
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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.
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- Filed December 1, 1995 and granted August 22, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 1, 2015.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 1, 2017.
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