a subtracter that receives an input motion video signal and a motion video signal, which precedes by 1 frame and from which noise is removed, and that obtains a difference signal indicative of a difference between said signals;

a first multiplier that increases/decreases the difference signal in accordance with a value of the motion video signal that is input to the subtracter, thereby obtaining a corrected difference signal;

a motion detection circuit that receives the corrected difference signal from the first multiplier, detects an amount of motion of the motion video signal, and outputs a coefficient varying in accordance with the amount of motion;

a second multiplier that multiplies the difference signal from the subtracter by the coefficient from the motion detection circuit;

an arithmetic unit that subjects the difference signal output from the second multiplier to addition/subtraction with the input motion video signal, thereby outputting a motion video signal, from which a noise component in the input motion video signal is removed; and

a memory unit that receives the noise-free motion video signal from the arithmetic unit, and outputs a motion video signal that delays by 1 frame to the subtracter.