Synthesis of speech signals in the absence of coded parameters
CA 2185745 C · Owner: Chen, Juin-Hwey · Inventors: Chen, Juin-Hwey
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A speech compression system called "Transform Predictive Coding" or TPC, provides for encoding 7 kHz wideband speech (16 kHz sampling) at a target bitrate, range of 16 to 32 kb/s (1 to 2 bits/sample). The system uses short-term and long-term, prediction to remove the redundancy in speech. A prediction residual is transformed, and coded in the frequency domain to take advantage of knowledge in human auditory, perception. The TPC coder uses only open-loop quantization and therefore has a fairly, low complexity. The speech quality of TPC is essentially transparent at 32 kb/s, very, good at 24 kb/s, and acceptable at 16 kb/s.
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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 17, 1996 and granted February 13, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 17, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 17, 2018.
- 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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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.