Depth-first algebraic-codebook search for fast coding of speech
CA 2213740 C · Owner: Adoul, Jean-Pierre · Inventors: Laflamme, Claude; Adoul, Jean-Pierre
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A codebook is searched in view of encoding a sound signal. This codebook consists of a set of codevectors each of 40 positions and comprising N nonzero-amplitude pulses assignable to predetermined valid positions. To reduce the search complexity, a depth-first search is used which involves a tree structure with levels ordered from 1 through M. A path-building operation takes place at each level whereby a candidate path from the previous level is extended by choosing a predetermined number of new pulses and selecting valid positions for said new pulses in accordance with a given pulse-order rule and a given selection criterion. A path originated at the first level and extended by the …
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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 5, 1996 and granted January 21, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 5, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 5, 2018.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.