Method for the coding of picture signals
CA 2328581 C · Owner: Herpel, Carsten · Inventors: Herpel, Carsten; Keesen, Heinz-Werner
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A hybrid Discrete Cosine Transform (DCT) coder processes blocks of (e.g. 8X8) pixels from interlaced or progressive scanned image signals. Processing of image lines by the coder is modified in the presence of image motion to avoid switching between 8X8 and 2X(4X8) transformations. For motion, the lines of two vertically superimposed image blocks are rearranged to produce first and second modified blocks. The modified first block contains pixels from lines in a first field, and the modified second block contains pixels from lines in an associated adjacent second field.
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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 April 14, 1992 and granted February 26, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 14, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 14, 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.