Apparatus and method for authentication of printed documents
US5912974A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 30, 1997 |
| Grant date | Jun 15, 1999 |
| Priority date | — |
| Expiry date | Apr 30, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2201/3271
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Printed document contents are scanned and digitized, using a conventional scanner, and displayed page by page on a screen. Using a conventional editor and an input device, the scanned and digitized document contents are edited before being used to generate a digital signature. This allows reading errors, which could invalidate a subsequent verification process, to be corrected. Using the editor, and an input device such as a mouse, the signing authority identifies on the screen different segments of the document, each segment containing data of a single type and selects for each segment a set of rules, among a group proposed by the system, for authenticating it. Then, for each segment, an edited digital form of the data contents are derived using the method defined in the rules. A hash value of the rules used and the edited digital form of the segment contents is calculated using a public hashing algorithm. Then the apparatus generates a digital signature of the edited digitized segments contents using the secret key of the authenticator. Finally, an authentication code comprising the edited digital form of each segment and the digital signature is printed on the document. To verif…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.