Method and apparatus for creating encrypted and decrypted television signals
US4642688A · kind A · utility
145Cited by
16References
24Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 21, 1985 |
| Grant date | Feb 10, 1987 |
| Priority date | — |
| Expiry date | May 21, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N7/1696
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for creating a television signal and encrypting or decrypting the signal at the same time. Luminance and chrominance information are received by the apparatus and stored in separate television scan line stores. The stored liminance and chrominance information is read out from their respective stores at a frequency corresponding to a desired format or standard to create the television signal. The signal may be simultaneously encrypted or decrypted by delaying the time at which the luminance and/or chrominance information is read out in accordance with an encryption or decryption key.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.