PURPOSE: To prevent occurrence of jitter distortion and inversion phenomenon on the picture by changing the clip level of a dark clip circuit synchronizing with a synchronizing signal and enabling to adjust clip level of a video signal section and a synchronizing signal section in different level.

CONSTITUTION: A synchronizing signal is separated and extracted from a composite video signal given to a terminal 1 by a synchronizing signal separating circuit 13. This synchronizing signal is given to a level switching circuit 14. A control signal is given from the level switching circuit 14 to a dark clip circuit 6 to switch clip level synchronizing with the synchronizing signal. Operation of the level switching circuit 14 is as follows. Resistance R2 and the second variable resistance VR2 and the position of a sliding terminal are adjusted, and adjusted with a control signal that becomes optimum level to the video signal section. Then, by incoming of the synchronizing signal, the first and second transistors Tr1, Tr2 are conducted, and voltage is superposed on the control signal through the first variable resistance VR1, and adjusted to become optimum level for the synchronizing signal section.