Design Challenge! Server w/ Many Analog SD Outputs

[lightbx]

Emphasis on Analog.

I have access to many many Sony Trinitron CRT monitors, which have BNC input and output, so daisy chaining is possible. I'm working on an art exhibition (read: tight budget) that calls for a large CRT video wall. They want multiple channels of video, not just the same content across every screen. I plan to use 6 Micca Speck G2 players (which have composite out), one for each channel. I will daisy chain 4 monitors together per channel. (24 monitors total).

But now this has me thinking about how to create a "mosaic" of CRT screens (a 6x4 array of 640x480 monitors) that could display one image across all 24 CRT's, with a Resolume server to map and control for bezel.

In an ideal world with a big budget:
- GTX1080
- 6 Datapath FX4's (2 daisy-chained on each of the 3 Displayport outputs, giving 8x screens per output)
- 24 HDMI -> RCA converters

If you really love troubleshooting and Tylenol:
- 3X NVS810
- Quadro Sync Card
- 24 Mini Displayport -> RCA converters

Who's got a better idea?
Anyone know how to downstream a single 4K texture to 24 discrete analog SD outputs? Is there any kind of hardware switcher/distribution system that can take HD digital input and output analog SD? Bonus points if they frame-sync!

[Warspite]

2 Decklink Duo2 (495*2) or 1 Decklink QUAD 2 (995) + SDI Distribution Amplifiers Blackmagic Mini Converter SDI Distribution (6*195$, 8 outputs each)+some cheap sdi to composite converters from ebay (56$ each) .

[Warspite]

USD56 is the price for new chineese converters (which can do up to 3G SDI)
All your signals will be sd, so you can find really cheap old used converters sdi to composite.

[He2neg]

You also may find some old pro hardware to rent for low money.

Ask your video rentals around your location and describe what you wanna do.

[lightbx]

I think the most affordable solution would be to dedicate a Raspberry Pi for each CRT monitor, paired with a Mini HDMI2AV adapter (Mini is the brand name, on AliExpress for $5.61 each), a 3-inch HDMI cable and RCA composite cable of the right length.

All Pi's would be connected with Static IP's to a 48-port Gigabit switch on a LAN. The switches retail for about $300, but are available for much cheaper. (I'm now imagining this system fitting into a small rolling rack, with the switch on bottom and the Pi's on drawers above...)

Using PiWall, an open-source (if a bit outdated) software (http://piwall.co.uk/) you can configure the monitors to display only the proper "tile" (portion) of the video you need. Being video mappers, we know these concepts. I would probably rely on a calculator and good old draughtsmanship on grid paper for this one, to get the configuration right.

All of the Pi's controlling the tiles (slaves) could be controlled by a PC with ffmpeg or even another Pi (master) via DHCP. Apparently the software retains sync via timecode as well.

Thanks for entertaining my thought process in public. Thought I'd share my findings. Credit goes to Spielberger Studios for coming up with the solution originally. Read about it here: https://www.raspberrypi.org/blog/crt-vi ... nt-1391229

[He2neg]

What i saw and can work at some situations as well:

Open all the old Monitors and just keep the Glas and part of the housing.
Now setup a projector behind it and use alle the Screens als rearprojection screen.

Its more a workaround but a simple one.