Noise filter
US4291333A · kind A · utility
22Cited by
5References
14Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 9, 1980 |
| Grant date | Sep 22, 1981 |
| Priority date | — |
| Expiry date | May 9, 2000 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/646
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A recursive digital filter is disclosed for removing noise from an incoming television signal. The filter couples the incoming television signal to a subtracter without substantial attenuation of the television signal. The subtracter also receives at an input an attenuated difference signal comprising a selected amplitude of the difference between the incoming signal and an earlier received signal which has been delayed for an interval corresponding to one television frame. The subtracter subtracts the attenuated difference signal from the incoming signal and develops an output in which noise is substantially reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.