Video signal discriminating apparatus
US4722004A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 25, 1986 |
| Grant date | Jan 26, 1988 |
| Priority date | — |
| Expiry date | Nov 25, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/10
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A video signal discriminating apparatus comprises a pulse width measuring part for measuring a pulse width of a vertical or horizontal synchronizing pulse within a composite synchronizing signal of a video signal, a period measuring part for measuring a period of the synchronizing pulse having the pulse width thereof measured in the pulse width measuring part, and a discriminating part for discriminating that the video signal exists when the measured pulse width and the measured period are within respective predetermined ranges and for discriminating that no video signal exists when the measured pulse width and the measured period are outside the respective predetermined ranges.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.