Method and apparatus for encrypting and for decrypting data arranged in a data sector
US6912661B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 15, 1998 |
| Grant date | Jun 28, 2005 |
| Priority date | — |
| Expiry date | Jan 15, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2211/007
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for preventing unauthorized use of DVDs on a DVD ROM drive. The method comprises a DVD disc that includes special data processing. When the DVD is replayed on a standard DVD ROM drive the invention causes the output of the DVD ROM drive to be erroneous, such that the computer cannot use the data. According to the invention, when encoding a disc, the error correction and/or error detection bits, check bytes, are moved into the normal or main data area. When this scrambled data is output from a standard DVD ROM drive, the data in the check byte area is lost and the information is not useable. For authorized use, this scrambling is reversed before sending video and/or audio data to the MPED decoder and AC-3 decoder respectively.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.