Question / Help Hardware for multiple HMDI inputs to record

[ratatat]

Hi all,

I'm trying to find the best hardware setup for recording multiple hdmi inputs. We were using a multiviewer (http://avitechvideo.com/products/sequoia.php) that combined 4 hdmi inputs into one, but it stopped working and so we're looking into replacements. Is there an advantage to using a device that combines 4 hdmi inputs versus a video capture card that takes 4 hdmi inputs?
What we're looking for is:
- record video from 4 sources
- layout: 1 big video on top, three others in a horizontal arrangement below (and it seems that obs would allow us a custom layout if we were to just feed in 4 sources through a video capture card)
- minimal delay in video displaying. We are a research lab that uses this setup to control what participants see on a screen and live-code how they react, and this live-coding will change what participants see- to accurate timing is really important.

I hope this is not too off-topic, please let me know if there's a better place in the forum to ask this question.
Thanks!

 

[Harold]

Probably the best bet would be a blackmagic decklink duo2 or decklink quad with hdmi to sdi converters.

 

[ratatat]

thanks much for your input! I read up on SDI and hdmi and SDI seems like a good choice - but since our video from the cameras comes in HDMI, will it be advantageous to convert to SDI?
I'm thinking of getting this 4 hdmi input capture card: http://www.avshop.ca/video/computer-video-hardware/magewell-pro-capture-quad-hdmi-card
just so there's one less conversion device that can break etc. But if there's a reason to convert I would go the SDI route.

 

[Harold]

That magewell should work not too bad, but I don't know if you could use multiple at the same time.

The converters I know of for HDMI to SDI are all lossless converters, so the biggest advantage you'd have with the decklink cards would be the ability to use SDI output cameras straight when you get to that point.

 

[ratatat]

thanks, Harold!