Synchronizing circuit
US5319706A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 3, 1991 |
| Grant date | Jun 7, 1994 |
| Priority date | — |
| Expiry date | Sep 3, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2005/91314
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
When a specific signal (such as copy guard signal) is added between horizontal synchronizing signals in a composite synchronizing signal, and the addition period of the specific signal is defined in a specific period on the basis of the vertical synchronizing signal, the composite synchronizing signal is masked to remove the specific signal, thereby obtaining a masked composite synchronizing signal. Afterwards, from the masked composite synchronizing signal, the horizontal synchronizing signal and vertical synchronizing signal are obtained. In the case of composite synchronizing signal containing noise, without masking, the horizontal synchronizing signal and vertical synchronizing signal are directly obtained from the composite synchronizing signal. Therefore, when noise is not present, the horizontal synchronizing signal and vertical synchronizing signal may be obtained without disturbing the video image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.