PURPOSE: To enable a very simplified circuit to correct the frame of a video signal outputted by a TV camera, by making a frame correcting circuit extract the peak part of a saw-tooth wave outputted synchronizing with a vertical driving pulse.

CONSTITUTION: Pickup tube 1a outputs R signal 1a1 to pre-amplifier 2a for amplification and saw-tooth wave generating circuit 3, on the other hand, outputs saw- tooth wave 3a to frame correcting circuit 4 synchronizing with, for example, a vertical driving pulse. Then, a video signal outputted from a TV camera is frame- corrected by the output signal of correcting circuit 4 which extracts the peak part of saw-tooth wave 3a. Consequently, the correction of a frame can be achieved with an extremely simple circuit constitution