Speech coding method and device for implementing the improved method
CA 1188423 A · Owner: International Business Machines Corporation · Inventors: Galand, Claude; Beraud, Jean-Paul; Esteban, Daniel
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract Method for coding a speech-originating signal. The spectrum of the initial signal covering a frequency range of 0-4000 Hz is split into 16 subbands each one, containing 12-bit coded samples. The samples of the 16 sub-bands are requantized in BCPCM at dynamically variable bit rates. For this, the sample flow of the sub-bands is divided into blocks of a given duration then each block is processed for deriving therefrom two scale factors, the difference of which is analyzed to define the sample block as transient or non-transient block. For each non-transient block, only one scale factor is retained, whereas for a transient block both scale, factors are retained. The signal samples of …
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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
- Granted June 4, 1985. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended June 4, 2002.
- 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.