Noise reducing system for video signal
US4618893A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 27, 1984 |
| Grant date | Oct 21, 1986 |
| Priority date | — |
| Expiry date | Jul 27, 2004 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/923
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A noise reducing system for a video signal, comprises a vertical pre-emphasis circuit supplied with an input video signal which is to be transmitted, for pre-emphasizing the input video signal and transmitting a pre-emphasized video signal to a transmitting system, and a vertical de-emphasis circuit supplied with a pre-emphasized video signal which is pre-emphasized by the vertical pre-emphasis circuit and is transmitted through the transmitting system, for de-emphasizing the pre-emphasized video signal. The vertical pre-emphasis circuit has a non-linear pre-emphasis characteristic for relatively emphasizing a high-frequency component of the input video signal in a vertical spatial frequency of a picture compared to a low-frequency component of the input video signal, with the degree of emphasis being reduced as the level of the input video signal increases. The vertical de-emphasis circuit has a non-linear de-emphasis characteristic for relatively attenuating a high-frequency component of the pre-emphasized video signal in a vertical spatial frequency of the picture compared to a low-frequency component of the pre-emphasized video signal, with the degree of attenuation being reduc…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.