A circuit for selectively controlling signal baseline and frequency emphasis. An amplifier with selectively controllable feedback circuitry allows higher frequency components of a signal to be emphasized over lower frequency components while also allowing control over the baseline of the signal. Additionally, a multiplexed video signal interface provides a multiplexed component video signal which includes component video signals with OSD data and user-controllable contrast, video gain and signal baseline, along with the ability to individually control such signal components.