Nonlinear RGB video signal processing
US5083198A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 19, 1990 |
| Grant date | Jan 21, 1992 |
| Priority date | — |
| Expiry date | Sep 19, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/69
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A nonlinear video signal processing system provides gamma correction to improve rendition of picture details near black. In addition, picture brilliance is improved using a brightness and frequency dependent enhancement circuit providing increased detail signal contrast in bright picture areas. In each color channel, the respective color signal is gradually separated into a low level amplitude signal portion and a higher level amplitude signal portion. The higher level amplitude portion is high-pass frequency filtered. The low level signal portion and the high-pass filtered higher amplitude signal portion are added to the original, linear video signal for producing a combined signal coupled to the kinescope. The low level signal portion is DC coupled to the linear signal and the high level signal portion is AC coupled to the linear signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.