Speech coding system
CA 2044751 C · Owner: Johnson, Mark · Inventors: Johnson, Mark; Taniguchi, Tomohiko
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A speech coding system operated under a known code-excited linear prediction (CELP) coding method. The CELP coding is achieved by selecting an optimum pitch vector P from an adaptive codebook and the corresponding first gain and, at the same time selecting an optimum code vector from a sparsestochastic codebook and the corresponding second gain. The system of the present invention is featured by special code vectors to be loaded in the sparsestochastic codebook, which code vectors are hexagonal lattice code vectors each consisting of a zero vector with one sample set to +1 and another sample set to -1.
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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 June 17, 1991 and granted January 16, 1996. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 17, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 17, 2013.
- 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.