Near-toll quality 4.8 kbps speech codec
CA 2031006 C · Owner: Communications Satellite Corporation · Inventors: Tzeng, Forrest Feng-Tzeng
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
There is described an improved apparatus for encoding an input speech signal into a plurality of coded signal portions (e.g. pitch, pitch gain b, Ci, G), the apparatus including a first computation circuit responsive to the input speech signal for generating at least a first (e.g. pitch and pitch gain b) of the coded signal portions, and additional means responsive to the input speech signal and to at least the first coded signal portion for generating at least a second (e.g. Ci and G) of the plurality of coded signal portions the first computation circuit comprising iterative optimization for determining an optimum value for the first coded signal portion assuming no excitation signal and, …
Read the whole patent
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 November 28, 1990 and granted June 14, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 28, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 28, 2012.
- 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.