Method for the estimation and recovering of general affine transform
US6904151B2 · kind B2 · utility
Inventors
Key dates
| Filing date | Jan 17, 2002 |
| Grant date | Jun 7, 2005 |
| Priority date | — |
| Expiry date | Nov 29, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2201/0601
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The present invention relates to the methods of estimation and recovering of general affine geometrical transformations which were applied to data, extensible to any other defined class of geometrical transformations, according to the preamble of the dependent claims. The parameters of the undergone deformation are robustly estimated based on maxima given by a parametric transform such as Hough transform or Radon transform of some embedded information with periodical or any other known regular structure. The main applications of this invention are robust digital still image/video watermarking, document authentication, and detection of periodical or hidden patterns. In the case of periodical watermarks, the watermark can also be predistorted before embedding based on a key to defeat block-by-block removal attack.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.