| 摘要 |
PURPOSE:To obtain various types of deformed wipe waves, by modulating each basic waveform data horizontal and vertical in the waveform memory so that new video special effect signal can stably be generated. CONSTITUTION:The output waveform from digital waveform memories 1H, 1V of horizontal and vertical basic waveforms, and the data set at fadar levers 21H, 21V are subtracted at subtractors 20H, 20V, waveform limit and waveform shape are made at limiters 22H, 22V, and both the limiter outputs are in level-comparison at a comparison selection circuit 23 to obtain video special effect signal Ss. Either one of video signals SA, SB is selected at a switch circuit 25 with this signals Ss to obtain wipe waveform So. Accordingly, in comparison with analogical production of basic and modulation waves, stable video special effect signal can be obtained, and since the data in which the initial phase of modulation wave of sinusoidal waves is sequentially shifted with time, can be stored in the waveform memories 1H, 1V, various types of wipe waveform can be obtained. |
