Perceptual audio coding
CA 2246532 A1 · Owner: Najafzadeh-Azghandi, Hossein · Inventors: Kabal, Peter; Najafzadeh-Azghandi, Hossein
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method and apparatus for perceptual audio coding. The method and apparatus provide high-quality sound for coding rates down to and below 1 bit/sample for a wide, variety of input signals including speech music and background noise. The , invention provides a new distortion measure for coding the input speech and training the codebooks, where the distortion measure is based on a masking spectrum of the input frequency, spectrum. The invention also provides a method for direct calculation of masking, thresholds from a modified discrete cosine transform of the input signal. The invention, also provides a predictive and non-predictive vector quantizer for determining the energy, of 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 September 4, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended September 4, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 4, 2020.
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Timeline
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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.