Copy-guard system and information recording medium used in the same system
US6556679B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 19, 1998 |
| Grant date | Apr 29, 2003 |
| Priority date | — |
| Expiry date | Nov 19, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2005/91364
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In an embodiment, a copy-guard system is provided that includes a decoding section for decoding digital data, which is encoded and error-correction-coded, from an information recording medium in which key information encoded for the digital data is recorded, an encoded digital data acquisition section for acquiring digital data encoded by error-correcting the digital data decoded by the decoding section, a detection section for detecting an error position and an error symbol value of the encoded digital data, identification information detection section for detecting an identification information representing whether the information recording medium is original or copied and which is replaced with a part of the digital data encoded and error-correction-coded, based on the error position and the error symbol value detected by the detection section, a determination section for determining whether a copy of the information recording medium is protected, and a copy protection section.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.