Data hiding method and system using statistical properties
CA 2222348 C · Owner: International Business Machines Corporation · Inventors: Shimizu, Shuichi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention provides a method to extract embedded information without providing original media data as information, and to extract the information with relatively low calculation cost. A data hiding method is provided for embedding information indicating a specific meaning into a media array expressing media data. The media array includes a plurality of array elements. The method includes the steps of: (a) preparing a pattern array having a plurality of array elements the pattern array, having at least a positive unit value and a negative unit value and the sum total of the, positive and negative unit values being zero; (b) specifying (N) number of hiding regions in the media array the …
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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 November 27, 1997 and granted October 29, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 27, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 27, 2019.
- 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.