Method and device for coding an audio signal by "forward" and "backward" lpc analysis
CA 2258695 C · Owner: Proust, Stephane · Inventors: Proust, Stephane
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention concerns a method and a device for coding an audio signal by "forward" and "backward" LPC analysis, the coding being produced by "forward" LPC filtering for non-stationary zones and on a synthetic signal based on "backward" LPC filtering for stationary zones. For each current LPC block (Bn) (10), the degree of stationarity of the digital audio signal is determined (11), and a "forward" or "backward" LPC analysis selection value is established (12) based on a decision function according to the stationarity , parameter. A "forward" or "backward" LPC analysis criterion is applied (13) to the analysis selection value to produce the audio signal coding before proceeding to …
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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 9, 1998 and granted February 11, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 9, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 9, 2020.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.