described later on the delay circuit 22 can be removed if the delay time of the edge detector 26 is zero or very small an input video signal a output from the delay circuit 22 is supplied to the mixer 23 an output video signal q from the mixer 23 is supplied to the frame memory 24 in which it is delayed by a delay time of one frame a delayed input video signal b output from the frame memory 24 is supplied to the mixer 23 the input video signal applied to the input terminal 20 is supplied to the edge detector 26 which detects an edge of the input video signal to generate an edge signal e indicative of the edge of the video signal the edge signal e is supplied to a nonadditive mixer nam 27 the nam 27 is supplied with two input signals and outputs an input signal of high level an output of the nam 27 is supplied to a frame memory 28 and thereby delayed by a delay time of one frame an output of the frame memory 28 is supplied to a damping coefficient multiplier 29 in which it is multiplied with a damping coefficient d 0 lt d lt 1 an output of the damping coefficient multiplier 29 is supplied to the nam 27 this output signal is also supplied to the mixer 23 as a mixing ratio control signal key signal c an operation of the video special effect generator according to the present invention will be described below with reference to fig2 a through 2d in input images of the input video signals a t 2 a t.