Signal recording apparatus, signal record medium and signal reproducing apparatus
US6516064B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 10, 1996 |
| Grant date | Feb 4, 2003 |
| Priority date | — |
| Expiry date | Aug 2, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2220/235
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A signal reproducing apparatus in which unauthorized decoding or copying is rendered difficult. The apparatus is configured for reproducing ciphered data from a disc-shaped record medium 101 on which there are recorded data ciphered by at least one encryption operation and the key storage site information specifying the arraying site for at least one key information item used for deciphering the ciphered data. The apparatus includes a reproducing head device 12 for reading out the ciphered data and the key storage site information from the record medium 101, a TOC decoder 219, a CPU 224 and a digital signal processing circuit 220 for decoding the ciphered data using the key information stored on the site designated based on the key storage site information.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.