Transform coded excitation for speech and audio coding
CA 2094780 A1 · Owner: Adoul, Jean-Pierre · Inventors: Laflamme, Claude; Adoul, Jean-Pierre; Salami, Redwan A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for coding speech is disclosed. This method, called TCX (Transform Coded Excitation) combines, features of time domain techniques such as CELP, (Code-Excited Linear Prediction) with features of, frequency-domain techniques such as TC (Transform, Coding), while avoiding their respective drawbacks. The invention preserves the principle of error minimization in the perceptually-weighted-speech(/audio) domain which is found in CELP along with techniques such as linear filtering and pitch prediction; yet, its circumvents the complexity of the CELP analysis-by-synthesis approach by using quantization. The invention also takes advantage of the efficient frequency-domain quantization …
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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 23, 1993. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended April 23, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 23, 2015.
- 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
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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.