Method for embedding and extracting text into/from electronic documents
US6940995B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 2, 2001 |
| Grant date | Sep 6, 2005 |
| Priority date | — |
| Expiry date | May 29, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2201/327
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention relates to a method and apparatus for authenticating various types of digital certificates by using a text embedding method. The execution of the present invention is divided into two case, one case including images in the certificate and another case not including the images in the certificate, according to the characteristics of the certificate. In the former case, a text embedding method is applied to images included in the certificate to embed a series of information text (a specific number of the certificate, and issuing organization, name of a person in charge, etc.) designated by a person who issues the certificate into the images. In the latter case, there is generated an image imperceptible to the human eve but having the same color as the ground color certificate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.