Video signal processing circuitry for compensating different average levels
US4175272A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 28, 1978 |
| Grant date | Nov 20, 1979 |
| Priority date | — |
| Expiry date | Aug 28, 1998 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/911
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Video signal processing circuitry for compensating a video signal having different average levels in alternate horizontal line intervals, such as in odd and even line intervals during a field or frame interval. A first average detector is operable during alternate ones of the line intervals, for example, during odd line intervals, for detecting the average level of the video signal in such alternate line intervals. A second average detector is operable during the remaining ones of the line intervals, for example, during the even line intervals, for detecting the average level of the video signal in such remaining line intervals. A compensating circuit is responsive to the difference between the detected average levels of the video signal in the alternate and remaining line intervals, respectively, for producing compensating signals. These compensating signals are combined with the video signal so as to minimize the difference between the average level of the video signal in successive line intervals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.