Method and apparatus for encoding-decoding a digital signal
CA 2066471 C · Owner: France Telecom · Inventors: Mahieux, Yannick; Duhamel, Pierre
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
36, The invention relates to a method and to apparatus for encoding-decoding a digital signal comprising a sequence of samples x(n). After a windowing operation h(n) performed by space-time weighting of the samples, the method and the apparatus consists in performing or enabling to be performed a modified discrete cosine transform of the samples to calculate the even order transformation coefficients: The coefficient Y2k are expressed in the form of an invertible complex transformation:, The invertible complex transformation is calculated using an auxiliary calculation equation:, The invention is applicable to encoding and decoding digital audio or video signals.
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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 July 16, 2002. 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.
- 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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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.