System and method for digitally marking a file with a removable mark
US6792535B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 17, 2000 |
| Grant date | Sep 14, 2004 |
| Priority date | — |
| Expiry date | Mar 17, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2201/327
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A system enables encoding of a removable mark into digital data, and decoding of the mark from the digital data. The system comprises an encoder and a decoder. The encoder includes a target area locator for locating in digital data a predetermined pattern of values that represents a flat area, and a marker for modifying values in the flat area to encode a mark into the flat area. The decoder attempts to extract the mark from the digital data. The decoder includes a mark area locator for locating a predetermined pattern of values in digital data, and an unmarker coupled to the mark area locator for examining the values to determine the state of each value and extract an embedded mark from the predetermined pattern of values.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.