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Black level calibration device for video cameras has control signal setting device that compares digital image signal black level with calibration value, sets control signal accordingly
Black level calibration device for video cameras has control signal setting device that compares digital image signal black level with calibration value, sets control signal accordingly
The arrangement has a circuit (200) for correlated dual scanning/automatic gain regulation that performs sample and hold and AGC (Automatic Gain Control) operations on an analogue image signal based on a black level clamp signal. A black level clamp circuit (260) generates the black level clamp signal based on a calibrated reference voltage. An analogue-to-digital converter (210) converts the analogue image signal output by the CDS/AGC (Compact Disc Spieler) Automatic gain control circuit into a digital image signal. A control signal setting device compares a black level of the digital image signal with a black level calibration value and sets a digital control signal accordingly. A reference voltage calibration device generates the calibrated reference voltage according to the digital control signal.
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