Release status: experimental [box doku]
|Description||Generating and glitching video signals in funky ways|
Video synthesizers generate or modify video to look somewhat weirdly, and have it react to external sources, e.g. an audio signal.
Trying to figure out what people have done and documented already.
Modify an incoming signal
Generate a new signal from scratch
- Good description on how to generate VGA signal using logic chips (see the logs): https://hackaday.io/project/9782-nes-zapper-video-synth-theremin
- ESP Version: https://github.com/smaffer/espvgax
- http://www.wiringdiagrams21.com/2010/11/14/video-vga-splitter-circuit-diagram-using-ecg2322/ (Uses obsolete part)
Glitch video with an audio signal
Basically following this guide.
Setup as described in the guide
Laptop VGA Out ---> VGA+Audio Merger with Diodes ---> Monitor Laptop Audio Out ----------^
Doesn't work, laptop turns off the VGA out.
Diodes, with VGA "Booster"
As above, but using a VGA matrix we had in the space as a VGA buffer
Laptop VGA Out --> VGA Matrix --> VGA+Audio Merger with Diodes ---> Monitor Laptop Audio Out ---------------------^
Works, audio signal a bit weak, not as much effect, also video signal is attenuated compared to video directly from the VGA out.
Audio mixer & EQ
Adding an audio mixer between the Laptop and the VGA+Audio merger allows to control the "volume" better, and allows to use the EQ of the mixer to influence the signal.
Laptop VGA Out --> VGA Matrix --> VGA+Audio Merger with Diodes ---> Monitor Laptop Audio Out --> Audio Mixer & EQ ---^
The EQ is fun to work with, smaller lines with the high pass, bigger lines with the low pass filters. Control over the volume of the signal is also great. As a side effect, you can also listen to the audio signal now.
No more diodes
Left out the diodes in favour of direct connection between matrix and monitor.
Laptop VGA Out --> VGA Matrix --> VGA+Audio Merger w/o Diodes ---> Monitor Laptop Audio Out --> Audio Mixer & EQ ---^
All still works, and the original video signal is much clearer now. Best thing so far.