Noise reducing system for video signal
US4607285A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 2, 1984 |
| Grant date | Aug 19, 1986 |
| Priority date | — |
| Expiry date | Feb 2, 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 supplying an output signal to a transmission system, and a vertical de-emphasis circuit supplied with the video signal which has been pre-emphasized in the vertical pre-emphasis circuit and has been transmitted through the transmission system. The vertical pre-emphasis circuit has a characteristic for relatively emphasizing the level of high-frequency components of the input video signal having spatial frequencies in a vertical direction of a picture, compared to low-frequency components of the input video signal. On the other hand, the vertical de-emphasis circuit has a characteristic for relatively attenuating the level of the high-frequency components of the pre-emphasized video signal having spatial frequencies in the vertical direction of the picture, compared to the low-frequency components of the pre-emphasized video signal. The characteristics of the vertical pre-emphasis circuit and the vertical de-emphasis circuit cooperate so as to reduce noise having high spatial frequencies in the vertical direction of the picture.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.