Video signal scrambling system employing full line reversal and double burst coding
US4663659A · kind A · utility
17Cited by
3References
16Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Oct 31, 1985 |
| Grant date | May 5, 1987 |
| Priority date | — |
| Expiry date | Oct 31, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N7/1696
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A memory reverses the sequence of samples of selected lines of a composite video input signal without separating the color burst and chrominance components of the lines thereby preserving chroma-burst phase integrity of scrambled lines. A burst inserter adds a second color burst component to the normal and reversed sequence lines to preserve the secrecy of the scramble code. A descrambler includes a memory for restoring the sample sequence and removing the extra color burst component.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.