| 摘要 |
PURPOSE:To generate a superimposed video with a high degree of freedom by providing an A-D conversion circuit converting a superimposing signal into a digital signal, a storage medium, a D-A conversion circuit converting the digital signal into an analog signal and a circuit mixing the superimposing signal with a video signal. CONSTITUTION:When a memory button 19 is depressed, a microcomputer 18 supplies a sampling pulse 33 to a sampling circuit 10 to sample a comparator output signal 32 and to hold the sampled signal in a hold circuit 11, an output signal 34 is converted into a digital signal by an A-D converter 12 and stored in an IC memory 13 as a digital data. In reading a read button 20, the microcomputer 18 supplies a sampling pulse 35 to the IC memory 13 and a D-A converter 14, which converts the digital data into an analog signal, which is mixed with a video signal by a signal converter 16 to form a superimposed video signal.
|
