So I downloaded vMix 23 to give it a whirl.

I have a Decklink Quad 4 HDMI card. I have a video camera connected into the Decklink port 4 and I have another computer's (a laptop) display output connected to the Decklink port 1. vMix has no issue assigning the camera as an input but I cannot figure out how to use the laptop display output as an INPUT source to vMix. I've tried everything I can think of and I can't get the laptop display to be recognized as an input in vMix.
How do you do this?

This is a no-brainer in OBS - took 5 seconds to get this setup up and running in OBS. Why is this such a mystery in vMix?

What am I not seeing?
There is no input option in the list that is something like "GENERIC" where I can just choose the Decklink card and select an input port and have the video from that port as a source in vMix.

I'd appreciate any help on how to achieve this.

Did you try screen capture or NDI o see if the laptop appears?

If it's coming through your decklink card it'll be under "cameras". You're best of using NDI, plenty of info available in the help section.

OK. I did some more checking.

Using vMixDesktopCapture NDI I was only able to maintain a 18-20fps frame rate from the laptop to the vMix Broadcast Computer at 1920 x 1080. It worked but not to what I was desiring.

I did some more experimenting in the 'Camera' setup (since the capture card inputs only show up as 'Cameras') and was unsuccessful with whatever setting I tried.

Finally, I started experimenting with the 'display settings' for the secondary monitor (the extended display) on the laptop. I succeeded in having vMix receive the laptop signal through the capture card when I changed the refresh rate of the secondary monitor to 30Hz. That seemed to be the magic number (even when I changed my project settings to 60p and left the laptop secondary monitor refresh rate to 60Hz it did not work). It was only when I set my laptop secondary monitor settings to output at 30Hz that vMix successfully received the signal.

Thanks for your help.

Hopefully my experience can help someone else.

I don't believe it was the Decklink card at all - it was vMix.

Same laptop output, same card input, 60Hz refresh rate, 1080p and OBS had no issues receiving that content through the decklink card. vMix was puking at those settings.


Just so others don't get off with any false claims presented in this thread, here are the specs on the card:

Video Support for HD-1080p: 23.98, 24, 25, 29.97, 30, 50, 59.94, 60

Bottom line:

The card was just fine with what I was feeding it. vMix was not.

Bingo! That's my point and my frustration with vMix.

Why do I have to be locked into a 'Camera Input' model in order to access the capture card inputs??
Why isn't there an 'INPUT' in the list specifically for a 'computer feed'??

All I'm looking for is an INPUT that, in essence says, "ingest whatever signal appears at my input card, port such and such". Why does the signal have to be pigeon holed onto a camera setting?

I can't possibly be the only one out there who needs something like that - without having to install some NDI utility on the computer whose output that I want to 'ingest'.

I can confirm that on my computer*, vMix does not recognize all resolutions of my Laptop**, seen by the BM-HDMI card.
But i can confirm, that 1920x1080 refresh rates are working up to 59.94p.

* Xeon E5-1650, vMix 23.57 4K, Quadro RTX4000, Win10-2020, Decklink Quad2 and Decklink Quad HDMI Recorder, Decklink Driver 11.5.1
** the laptop was an ASUS, i5 PC with Intel UHD620 Graphics

The HDMI output of my laptop was first detected by the Xeon PC as 1900x1200, but without picture in vMix.

I tried the following display properties in Windows on the laptop:
The resolutions suggested in Windows are determined by the EEDI of the BM HDMI card.

vMix does not have the 1920x1200 resolution suggested by the laptop.
but...
in vMix, 1920x1080, 25p selected, vMix recognizes it as 4096x2160, 25p.

HD
1920x1080-32-Bit-25i - OK (in vmix as 50i)
1920x1080-32-Bit-29i - OK (in vmix as 59.94i)
1920x1080-32-Bit-30i - OK (in vmix as 60i)
1920x1080-32-Bit-50Hz - OK (in vmix as 50p)
1920x1080-32-Bit-59Hz - OK (in vmix as 59.94p)
1920x1080-32-bit-60Hz - no picture

1920x1440 - 32-Bit-23Hz - OK (in vmix as 4096x2160, 23.98p

vMix does not have the 2048x1152 resolution suggested by the laptop.
vMix does not have the resolution of 2560x1600 suggested by the laptop.
vMix does not have the resolution of 2560x1920 suggested by the laptop.
vMix does not have the laptop's suggested resolution of 2560x2048.
My laptop does not have the 2048x1556 resolution suggested by vMix.

When trying to select any resolution of 2560x1440 at the camera input, the vMix error message UNSUPPORTED VIDEO FORMAT

UHD
3840x2160-32-Bit-23Hz - OK (in vmix as 23.98p)
3840x2160-32-Bit-24Hz - OK (in vmix as 24p)
3840x2160-32-Bit-25Hz - OK (in vmix as 25p)
3840x2160-32-Bit-29Hz - OK (in vmix as 29.97p)
3840x2160-32-Bit-30Hz - OK (in vmix as 30p)

My laptop does not have higher UHD resolutions

I figured I'd revive this thread. To make life easier I bought a little 11 inch laptop with an HDMI out. It only has 60 Hertz setting, so the above tweaks didn't work. I used 1080 by 720 with 60hz and it recognized the little laptop. I'm running it into the Deck Link Quad. This works better for me than NDI. Hope this helps!