System and method for authorized compression of digitized music
US7082413B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 24, 1999 |
| Grant date | Jul 25, 2006 |
| Priority date | — |
| Expiry date | Apr 9, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B20/00884
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A system and method for enabling authorized music from a CD or DVD to be compressed by a user for the user's own use, but to prevent the recompression of unauthorized music from, e.g., the Internet, includes hashing the music during recording with a cryptographic hash, and then signing the hash with a digital signature derived from the hash. Subsequent unauthorized compression and recompression will destroy the digital signature. Accordingly, music to be recorded is hashed to obtain a test digital signature and if, after hashing, the test digital signature matches the digital signature accompanying the music, compression and recording are allowed to proceed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.