Method of coding 32-kb/s audio signals
CA 2075754 C · Owner: Thierer, Gebhard · Inventors: Fesseler, Peter; Thierer, Gebhard
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
For audio signals (50 to 7000 Hz), good speech quality is to be achieved at a data rate of 32 kb/s (also for music signal(s), which requires a considerably greater data reduction than hitherto known. For a further data reduction of the magnitude values of the coefficients obtained by FFT, the absolute threshold of hearing and a relative threshold of hearing known as masking effect are taken into account in fixing the quantization levels. This is followed by a variable quantization.
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 August 11, 1992 and granted February 17, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 11, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 11, 2014.
- 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.