Combined runlength coding and variable length coding for video compression
CA 2520652 C · Owner: Chen, Wen-Hsiung · Inventors: Chen, Wen-Hsiung; Pelton, Gregory D.; Wu, Fang
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method and an apparatus to encode a series of quantized coefficients of a transform of a block of image data. The transform is such that 0 is the most likely coefficient amplitude and 1 is the next most likely coefficient amplitude. The method includes forming modes for each encountered non-zero amplitude and forming events for the modes in the mode-~modified series formed by setting to zero all non-zero amplitudes other than the amplitude defining the mode. An event for modes for amplitudes greater than 1 is a run of none or more zero-valued coefficients followed a non-zero amplitude in the modemodified series. In one embodiment, a first mode is defined for amplitude 1 wherein an …
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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 March 3, 2004 and granted June 7, 2016. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 3, 2024.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 3, 2026.
- 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
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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.