OBS to display 8 HDMI sources

[TommiB]

Hello,
I want to use OBS to display 5 of 8 HDMI sources at the same time, output via stream and Decklink MiniMonitor card.

I realize that I need a fast computer.
What kind of graphics card is needed for something like this?

 

[koala]

Your post isn't clear. What/how many sources do you want to input and in what format (hdmi capture or whatever), and what/how many scenes or sources do you want to output and in what format (hdmi monitor or whatever).

 

[TommiB]

Your post isn't clear. What/how many sources do you want to input and in what format (hdmi capture or whatever), and what/how many scenes or sources do you want to output and in what format (hdmi monitor or whatever).

I would like to use 2 4HDMI input cards and display up to 7 sources at the same time.
Almost like a video quad splitter.
I will set up different scenes for the different arrangements.

I would also like to output HDMI format - simultaneous streaming on Twitch.

 

[TommiB]

No one can tell me what gpu i need?

 

[AaronD]

No one can tell me what gpu i need?

No change from the standard requirements, because the GPU doesn't see anything different.

Gathering sources and compositing them (putting them together like a PowerPoint slide, but with live sources) is a CPU thing. Once you have that result, the uncompressed frame with a single color for each pixel, is passed to the GPU to squash into a reasonable-sized bitstream to send out.

That's all the GPU does. It's a lot, all by itself, which is why that specific task is offloaded, but everything else is still CPU.

 

[koala]

It's probably more important to choose a GPU that comes with enough ports to connect your 7 sources. As far as I know, there are just GPUs with up to 4 hdmi or displayport outputs, so you need 2 of them. Or displayport (instead of hdmi) has the feature to chain monitors, so you're able to connect multiple monitors to one displayport output if you use a displayport hub. However, that's not hdmi, that's a displayport feature, so you need monitors with displayport input.

 

[AaronD]

It's probably more important to choose a GPU that comes with enough ports to connect your 7 sources. As far as I know, there are just GPUs with up to 4 hdmi or displayport outputs, so you need 2 of them. Or displayport (instead of hdmi) has the feature to chain monitors, so you're able to connect multiple monitors to one displayport output if you use a displayport hub. However, that's not hdmi, that's a displayport feature, so you need monitors with displayport input.

I understood it as going the other way. 8 cameras feeding into OBS, which makes a grid of them on a single canvas, and sends that same canvas to several different places, only one of which is physical. But like you said earlier, it's not *entirely* clear.

 

[TommiB]

Sorry for the not so clear descriptions.

I would like to use 2 HDMI grabber cards with 4 inputs each on a PC and create different scenes with OBS. Up to 7 HDMI sources can be displayed in reduced size at the same time.

The result is to be streamed and output as an HDMI signal using a Blackmagic Decklink MiniMonitor card.

The whole thing 24/7 without interruption.

 

[Tomasz Góral]

I got 4ch (hdmi) blackmagic, 1ch (sdi/hdmi) blackmagic, PCIE Card and connect 3 USB grabber. In sum 8 input.
All 1080p25 signal.
I got I7-6700 and GTX1650.

 

[TommiB]

I got 4ch (hdmi) blackmagic, 1ch (sdi/hdmi) blackmagic, PCIE Card and connect 3 USB grabber. In sum 8 input.
All 1080p25 signal.
I got I7-6700 and GTX1650.

Thank you for your explanation.
How many inputs do you display at same time?

Best regards Thomas

 

[Tomasz Góral]

I got preview all input on second monitor.
But few year ago i connect monitor plus 4 TV in the same time.