GENERATOR OF SPECIAL EFFECT WAVEFORM

摘要

PURPOSE:To avoid the generation of a black edge on an effect screen despite a quick operation of a fader by delivering two effect waveforms of different delay times to a fader control signal. CONSTITUTION:The outputs of horizontal and vertical cycle basic wave generating circuits 21 and 22 are added together or mixed with no addition through a waveform compounding circuit 23. Thus a waveform is compounded. This waveform is sliced by a slicing circuit 24 by a fader control signal Vf to obtain an effect waveform output Vd for digital special effect device. While the signal Vf is delayed by a delay circuit 26, and a slicing circuit 25 is actuated by the delayed signal. Thus an effect waveform output is obtained for a special effect amplifier. This avoids the generation of a black edge on a compound screen even in case the fader control signal varies within three fields owing to a quick operation of the fader.