Visible authentication patterns for printed document
US7809152B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 14, 2003 |
| Grant date | Oct 5, 2010 |
| Priority date | — |
| Expiry date | Aug 16, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2209/608
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
Techniques for determining authenticity of analog forms such as packaging or documents (117). One of the techniques determines whether the analog form has been made directly from a digital representation (903) or by photocopying or scanning an analog form. The technique makes the determination by comparing (911) an original digital representation of a portion of the analog form with a digital recording (203) of the portion from the analog form and measuring differences in features that are affected by the operations of photocopying or scanning. The original digital representation (105) and the analog form may have a “noisy”, i.e., random or pseudo random pattern. Such noisy patterns may further be used for other authentication purposes, such as determining whether the portion of the analog form that has the noisy pattern has been altered and to carry hidden messages. The noisy pattern may carry a logo or may be part or all of a barcode.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.