Video signal processing apparatus for removing noise from reproduced signals
US4827342A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 24, 1987 |
| Grant date | May 2, 1989 |
| Priority date | — |
| Expiry date | Sep 24, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/21
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A video signal processing apparatus includes a digital vertical filter for passing a signal in a specific vertical high frequency band of a digitized input luminance signal and a digital nonlinear processing circuit having a nonlinear input-output characteristic for nonlinearly processing the signal from the vertical filter so that one of a luminance signal component and a noise component of the signal from the vertical filter is suppressed while the other is maintained as is or so that the luminance signal component is emphasized while the noise component is maintained as is or suppressed. The apparatus also includes an arithmetic operation circuit for arithmetically synthesizing the digitized input luminance signal and an output signal of the nonlinear processing circuit so that the noise component is canceled or the luminance signal is increased, thereby obtaining a digitized luminance signal having an improved signal-to-noise ratio in the specific vertical high frequency band.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.