PURPOSE: To remove the influences of the noise and saturation of a luminance signal by varying a removal level in the case of a low level removing operation to the high frequency component of the luminance signal.

CONSTITUTION: The high frequency component of a video signal amplified by an AGC amplifier circuit 120 and extracted by an HPF 5c is turned to a focusing evaluation signal by removing an amplitude level lower than a reference level at a low level removing circuit 45h and being integrated for each field at an integration circuit 5g. A high luminance detection circuit 21 detects the saturation of the video signal when there is any high luminance part inside a picture, and a saturate signal CS is sent to a reference level control circuit 22. The AGC amplifier circuit 120 sends a gain control signal GC to the reference level control circuit 22. When the saturation signal CS is received and the amplification factor of the amplifier circuit 120 is increased, the reference level control circuit 22 increases a reference level at the low level removing circuit 45h.