| 摘要 |
An improved video processing amplifier includes means for correcting for any black level distortion present in a composite video signal input for restoring the black level to a substantially undistorted video signal black level. The composite blanking and sync signals are removed from the composite video signal input prior to black level distortion correction and restoration. A window signal positionable in a central area of the associated video picture producable from the composite video signal input is provided to accomplish black level distortion correction and restoration, with this window signal being used to key a keyed clamp DC restoration circuit ON during the central area of the associated video picture information. Image enhancement is provided in the resultant output composite video signal in a single transistor state. In addition, both white and black peak level clipping is provided in a common clipping amplifier stage based on the saturation characteristics thereof.
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