Method and apparatus for transmitting an audio stream having additional payload in a hidden sub-channel
CA 2444151 C · Owner: National Research Council Canada · Inventors: Ding, Heping
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Methods and apparatus are provided for communicating an audio stream. A perceptual mask is estimated for an audio stream based on the perceptual , threshold of the human auditory system. A hidden sub-channel is dynamically allocated substantially below the estimated perceptual mask based on the characteristics of the audio stream, in which additional payload is transmitted. , The additional payload can be related to components of the audio stream that would not otherwise be transmitted in a narrowband signal or to concurrent , services that can be accessed while the audio stream is being transmitted. A suitable receiver can recover the additional payload whereas the audio stream , …
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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 October 3, 2003 and granted March 1, 2011. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 3, 2023.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 3, 2025.
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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.