Method for securing an image by means of graphical anti-counterfeiting means, method for securing an identification document, and secure identification document
US8428300B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Jul 7, 2009 |
| Grant date | Apr 23, 2013 |
| Priority date | — |
| Expiry date | Mar 6, 2030 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB42D25/309
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
The invention relates to a method for securing a first image by means of graphical anti-counterfeiting means and to a method for securing an identification document with such graphical anti-counterfeiting means. The invention also relates to a secure identification document that allows detecting either a fraudulent modification of the existing personalization or a fraudulent falsified document. For that, graphical anti-counterfeiting image is inserted into an identification image, each image being defined by a plurality of pixels. The characteristic level (for example grey level) of each pixel i of the graphical anti-counterfeiting image is linked, by a function F, to a matrix Ωi of pixels defined in the identification image, said pixels of the matrix Ωi surrounding the location i of a pixel of the graphical anti-counterfeiting image, said function F taking into account the characteristic level (for example average grey level) G(Ωi) and the texture level T(Ωi) of said matrix Ωi.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.