After the mid 90s boom in popularity glitch has become a critical part of contemporary popular esthetics. How to make Analog Video Glitches | Circuit Bending video discusses how to make unique analog “glitch” textures for your next video:
Karl Klomp’s Dirty Video Mixer certainly gets about. It really is the easiest and most useful diy video project to get started with. here are some projects I found online…
This very simple circuit simply does analogue mixing of two composite video signals. If the video signals are synced together, it will mix them together quite OK. When the 1 kohm potentiometer is at one end, one video signal gets through as it is. When it is turned towards center, the video signal gets attenuated and some part of other video signal gets mixed in. There are also switches that allow to control which side of the potentiometer is connected to which video input.
This kind of simple video mixing can work as video fader from one source to another if the video signal is black&white composite video and the video sources are synced together. In case of color composite video this can work but is usually messy with the video color information handling.
In most cases the normal consumer video sources are not synced together, so we get a mix where the video signals are mixed together at “random” timing. This creates a sum of them, which is somewhat mess on the sync signals and color information. Typical CRT TV can somewhat decode something useful out of this mess, and you get the video glitch effects at certain settings and or useful video at all at some other settings. The colors in the video become messy because the color information coding of those two video signal is not in sync.
Please note that the mixing method used here is not in any way correct way to mix not synced video sources. It generates usually signal that does not usually match the official video standard (levels, sync timing and impedance) but in many cases get thing “close enough” that normal TV can show it.
Dirty Mixer example video:
If you want to see the result of mixing video sources out of sync, the “Dirty Video Mixer” is your new toy, and it will look like trying to watch the scrambled channels.
Hare is one video example of effects made with dirty video mixer and some other equipment. The source material was a VHS of video feedback (camera + monitor) through a circuit bent processor (dirty mixer) and a DVD of animated loops of diagonal lines created in Flash.
When I tested with my own Dirty video mixer circuit protype, I found one quite expected limitation of dirty video mixer: works usually work acceptably only with analog TVs.
If you have digital video equipment (flat TV, video projector, video processor deices) the results can be different looking glitches or missing video sync. Usually the results are somewhat different looking than with analog CRT display (not that nice). Not having anymore any large color CRT TV around limited the usability of this dirty video mixer.
More video links:
Somewhat related projects: