Method of document protection
US8120795B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Apr 29, 2006 |
| Grant date | Feb 21, 2012 |
| Priority date | — |
| Expiry date | Feb 16, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G2215/00932
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
This invention relates to a method for preventing a copy of document, belonging to a technical field of entire copy protection of document. In the prior art, for some important documents, specially the secret ones, the reproduction of this kind of document is usually prohibited by its owner because of the security. But the technique in the prior art can not solve the problem of preventing unauthorized reproduction. The method of the present invention is intended to embed a shading pattern under the original image of anti-copy document by an application program installed in the copy device, and decide whether the document can be copied legally or not. By the method of present invention, it is possible to detect the watermark information of the anti-copy document accurately and quickly, and prevent the reproduction of the anti-copy document thoroughly. Moreover, an additional memory space is no need.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.