CCD dark mean level correction circuit employing digital process

Details CCD dark mean level correction circuit employing digital process CCD dark mean level correction circuit employing digital process

1994-10-31

1997-08-19

Tran, Thai

Television

Camera, system and detail

Combined image signal generator and general image signal...

348255, 348534, 348697, 358483, H04N 964

Patent

active

056593554

ABSTRACT:
A digital black clamp circuit for calibrating the black level of an image signal produced by an imaging device, such as a CCD sensor. The digital black clamp circuit comprises a source of a video signal having a first interval of black level pixels and a second interval of image pixels; a differential amplifier having first and second inputs and an output, wherein the source is coupled to one of the first and second inputs; an A/D converter coupled to the output of the differential amplifier; a digital signal processor coupled to the A/D for accumulating and averaging digital black level pixels; a D/A converter coupled to the digital signal processor; and a control for selectively uncoupling the D/A converter to the other of the first and second inputs of the differential amplifier during the first interval of the video signal; and for coupling the D/A converter to the other of the first and second inputs during the second interval of the video signal to clamp the image pixels to an average black level.

REFERENCES:
patent: 4786969 (1988-11-01), Shouji et al.
patent: 4907084 (1990-03-01), Nagafusa
patent: 4974072 (1990-11-01), Hasegawa
patent: 5038225 (1991-08-01), Maeshima
patent: 5057920 (1991-10-01), Wilkinson
patent: 5105276 (1992-04-01), Schrock
patent: 5142354 (1992-08-01), Suzuki et al.
patent: 5189528 (1993-02-01), Takashima et al.
patent: 5278658 (1994-01-01), Takase
patent: 5341218 (1994-08-01), Kaneko et al.
patent: 5448306 (1995-09-01), Koyama

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