Encryption and decryption (scrambling and unscrambling) of video signals
US5553141A · kind A · utility
33Cited by
20References
55Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 24, 1983 |
| Grant date | Sep 3, 1996 |
| Priority date | — |
| Expiry date | Jun 24, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N7/169
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A video signal is encrypted by pseudo-random variation of portions of lines thereof to be horizontally scanned that are devoid of video information. Thus, the durations of line blanking intervals may be varied. The variation is done in accordance with an encryption keys which is employed at the receiver to decrypt the encrypted video signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.