PURPOSE: To prevent distortion in a waveform of a video signal.

CONSTITUTION: An H driver 4 driving a horizontal transfer section H of a CCD image sensor 1, a sample-and-hold circuit 21 receiving an output of the CCD image sensor 1 and a clamp circuit 22 are activated continuously in response to a start trigger. An S driver 3 driving a storage section S is driven in response to an output control pulse to extract video information only for a period commanded by a pulse generating circuit 25. When the sample-and-hold circuit 21 and the clamp circuit 22 are operated continuously, the video information is received to conduct proper signal processing.