Method of extracting digital watermark information and method of judging but value of digital watermark information
US6456727B1 · kind B1 · utility
13Cited by
5References
6Claims
0Family size
Assignee
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Key dates
| Filing date | Mar 10, 2000 |
| Grant date | Sep 24, 2002 |
| Priority date | — |
| Expiry date | Mar 10, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2201/0065
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A digital watermark information is extracted from geometrically deformed image without using a calibrating digital watermark. Pixel data at positions predetermined in an X-Y coordinate used when embedding the watermark is extracted from image data in which the digital watermark has been embedded for given pixel data and compared with a reference value to determine whether the watermark has been embedded in the pixel data concerned or not. This processing is repeated until it is confirmed that the information is embedded in the pixel data concerned, while applying geometric deformation to the image data.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.