Video signal reproducing apparatus having a noise reduction circuit
US4682251A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 20, 1985 |
| Grant date | Jul 21, 1987 |
| Priority date | — |
| Expiry date | Mar 20, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/911
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A video signal reproducing apparatus comprises a reproducing circuit for reproducing from a recording medium a pre-recorded video signal having field correlation and having a predetermined band, and a noise reduction circuit supplied with a reproduced video signal from the reproducing circuit for essentially reducing noise included within the reproduced video signal. The noise reduction circuit comprises first and second subtracting circuits supplied with the reproduced video signal from the reproducing circuit, a one-field delay circuit for delaying an output of the first subtracting circuit by a predetermined time period and for supplying a delayed signal to the second subtracting circuit, which predetermined time period is equal to one field or a time period which is a natural number multiple of one horizontal scanning period and is extremely close to one field, and a limiter for amplitude-limiting an output of the second subtracting circuit and for supplying an amplitude limited signal to the first subtracting circuit. The output of the first subtracting circuit is obtained as an output of the noise reduction circuit. The one-field delay circuit has a transmission band which is…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.