Patent ID: 6650371
Filing Date: 2003-11-18
Classification: H04N

Abstract:
An apparatus including a signal multiplexor for multiplexing video image, on-screen-display (OSD) and display control signals, comprising:a first control circuit that upon receiving a reference signal, a contrast control signal and a clamped video signal provides a first controlled signal with a contrast-controlled video component; a first signal combining circuit, coupled to said first control circuit, that in response to a first combining control signal receives and selectively combines an OSD signal and said first controlled signal to thereby provide a first combination signal with said contrast-controlled video component and an OSD component; a second control circuit, coupled to said first signal combining circuit, that upon receiving said first combination signal, said reference signal and a gain control signal provides a second controlled signal with a contrast-controlled and gain-controlled video component and a gain controlled OSD component; a third control circuit that upon receiving and combining a brightness control signal and a bias control signal and receiving said gain control signal provides a third controlled signal with a gain-controlled brightness control component and a bias control component; and a second signal combining circuit, coupled to said second control circuit and said third control circuit, that in response to a second combining control signal receives and selectively combines said second and third controlled signals to thereby provide a multiplexed signal with said contrast-controlled and gain-controlled video component, said gain-controlled OSD component, said gain-controlled brightness control component and said bias control component.