VIDEO MIXING/SPECIAL EFFECTS AMPLIFIERS

摘要

Amplifier apparatus for operating on plural video signals to provide signal mixing, special effects and the like employs parallel video signal processing circuits which supply their output signals to a common video mixer. A keying signal processor is included for developing control voltages for separately varying video gain in the video processing circuits on a time shared basis. The composite arrangement thereby allows independent level control for the multi-channel video information vis-a-vis control signals such as synchronizing signals and/or a color burst.