Recording and reproducing apparatus for detecting the presence or absence of a copy guard to prevent false processing of noise signals
US5459583A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 21, 1994 |
| Grant date | Oct 17, 1995 |
| Priority date | — |
| Expiry date | Jul 21, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2005/91314
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A video signal recording and/or reproducing apparatus includes a copy guard processing detecting current which can correctly judge whether or not a copy guard is applied to an input video signal and prevents copy guard processing from being applied to a video signal to which a copy guard is not applied. The copy guard processing detecting apparatus includes a first circuit for receiving an input video signal which includes a plurality of false synchronizing signals for prevention of duplication inserted in a vertical blanking interval thereof and for counting the number of the false synchronizing signals, a second circuit for counting the number of synchronizing signals in an image interval of the input video signal except the vertical blanking interval, a discriminating circuit for discriminating whether or not copy guard processing is applied to the input video signal from the count values of the first and second circuits, and a recording system for receiving and recording the input video signal based on the results of the copy guard discriminating operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.