Sequencing data blocks to provide hidden data on a recording medium
US7805764B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 31, 2000 |
| Grant date | Sep 28, 2010 |
| Priority date | — |
| Expiry date | Mar 31, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B20/00086
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Method and apparatus for providing a hidden signature to a recording medium, such as an optical disc (102). The hidden signature is generated in relation to the selected sequencing of data blocks (132, 134, 136, 138, 140, 142). A plurality of) mutually exclusive, valid possible states are identified for each of the data blocks (202), each state conforming to requirements set forth by a published standards document to which the optical disc conforms. A different logical value is assigned to each of the possible states, and the hidden signature is selected as a multi-value logical word comprising a sequence of the logical values (204). The hidden signature is thereafter written to the optical disc by writing a set of corresponding data blocks at selected locations on the optical disc having states corresponding to the multi-value logical word (206). The hidden signature thereafter facilitates copy protection or forensic tracking efforts (208).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.