Video camera with a function to correct defective pixels of solid state image pickup device and method of correcting defective pixels of solid state image
US5625413A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 6, 1995 |
| Grant date | Apr 29, 1997 |
| Priority date | — |
| Expiry date | Jun 6, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N25/71
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
When defective pixels of a solid state image pickup device of a video camera are corrected by signal processes, a white spot noise is detected by closing an iris and by comparing the signal level and a level of only a dark current. Further, in this case, a gain of an AGC circuit for controlling a gain of a video signal is raised and a precise detection is executed. By executing such a detecting operation at the time of turn-on or turn-off of a power source, the user is not annoying. In the ordinary photographing, a reference level in detection of a white spot noise is set to an optimum value in accordance with a temperature of the solid state image pickup device or its peripheral temperature or the gain of the AGC circuit so that the white spot noise detection is not influenced by the temperature of the solid state image pickup device or the operating state of the AGC circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.