A perceptual compression and robust bit-rate control system
CA 2250284 C · Owner: Lucent Technologies Inc. · Inventors: Pauls, Richard Joseph
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of compressing a source (e.g. a video signal a still image, an audio signal, etc.) is disclosed that does not require the transmission of changes in the quantization step size and more evenly affects the fidelity of the source than techniques in the prior art that change the quantization step size at various points in the compression process. An illustrative embodiment of the present invention involves transforming a source (e.g. a video frame audio sample, etc.) into m coefficients in well-known fashion, wherein each of the m coefficients is represented by a known number of bits. Then only n of the m coefficients are used for transmission or storage as appropriate, where the n …
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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 14, 1998 and granted March 5, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 14, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 14, 2020.
- 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.