by mad-matt » Wed Jan 24, 2018 12:15 am
Hi Doug,
Maybe someone will have better advice for your situation.
First, what kind of LED screen is it ? Is it taking a DVI signal ? Did you check the latency already ?
If there is about one frame latency, you can make a Spout loopback for each projector, so you'll have 4 projectors in MadMapper: 2 where you do the mapping and that are published to spout, and two other that are assigned to the real projectors and that will just display a Quad with the corresponding spout input. That will make one frame latency, no more.
If you have a BlackMagic device with HDMI input you can also do a hardware loopback (it will have more than one frame delay) but that will use more resources, however since you're only using 2 projectors, on a good computer you can use more.
If you use NDI loopback (like the spout setup described above) you'll have more latency, but it will do video compression / decompression so it depends on your hardware. 2 Full HD streams encoding + decoding you have to check.
Maybe there are spout tool for that, no idea...
If your video content is just a movie, you could have two versions of the same movie with a few frames delay, then start them exactly at the same time (the version for LED screen + the version for projectors) and it will stay in sync (we handle the playback with high resolution so I'm confident the two movies wouldn't drift even after a few days)
Cheers
Matt