Question / Help Are Dual Output Mixes Possible?

[AllenKnapp]

Right now, at my church, we have an issue with an obstructed view from the balcony when people are seated. I am interested in implementing a live video solution to address this issue but would like to be able to eventually also use it to feed into live internet streaming.

I first considered feeding the NDI camera video directly into ProPresenter (with NDI Syphon) and using it as a live background during the sermon slides. But I have learned that there would probably be too much latency (e.g., 200ms) between the sound and the video. So I understand the solution to this is to put the two signals (NDI video and ProPresenter) into a video switch and combine in the switch to minimize the latency.

So here is what I am hoping to do:

1. Mixing live video from NDI PTZ camera(s) with lower third graphics from ProPresenter and displaying the mix on our projector. The live video would only be showing part of the time (e.g., during the sermon) and serves the purpose of letting the people in the back of the balcony see what's happening on stage. So the ProPresenter would be lower third during the sermon (showing sermon notes) but would be full screen during worship music, showing lyrics on the screen (as we do now without a camera).

2. A secondary need is to stream a different output mix live to the internet. The second mix would have lots of live video of worship music, announcements, baptisms, etc., with the same ProPresenter output but mainly lower third over the live video.

I believe that a salesman told me that switchers like the Realtek Tricaster Mini can do this, but is this type of thing possible with OBS?

Thanks,
Allen

 

[Narcogen]

Sort of?

One instance of OBS can receive multiple camera and NDI feeds and produce different NDI feed(s) as well as one stream output.

You can add a dedicated NDI filter to one video source.

You can also produce separate NDI feeds of your Preview and Program outputs, so you could theoretically produce two separate NDI feeds from two different scenes.

 

[AllenKnapp]

Sort of?

One instance of OBS can receive multiple camera and NDI feeds and produce different NDI feed(s) as well as one stream output.

You can add a dedicated NDI filter to one video source.

You can also produce separate NDI feeds of your Preview and Program outputs, so you could theoretically produce two separate NDI feeds from two different scenes.

I forgot to say that my projector does not accept NDI (only HDMI). So it sounds like this suggestion would involve feeding the NDI output to a mac or pc that would send it to the projector via HDMI? I would think I would introduce latency again by doing this. Or maybe there is a dedicated device to convert NDI to HDMI?

Or could I have an HDMI output from OBS feeding the projector and a different stream output for the internet?

 

[koala]

Or could I have an HDMI output from OBS feeding the projector and a different stream output for the internet?

Yes, you can connect your projector to some hdmi monitor output of your PC. This way the projector shows up as monitor on your PC. Then right-click any scene you want to output on that monitor and choose "Fullscreen Projector (Scene)" and choose the corresponding monitor. This works independently from streaming. You can output arbitrary scenes with this, even single sources. Every element in the scenes and sources window has the option of being output to a projector.

 

[AllenKnapp]

How much (if any) latency should I expect on the HDMI output, assuming a decent powered PC with SSD and ample memory?

 

[koala]

How much latency has a monitor? None?

 

[AllenKnapp]

koala, my question about latency was referring to the video latency that might be introduced by the computer that OBS is running on. If I have one mix going to my projector via the HDMI output of the computer, and another mix going out of the network to be streamed, how much latency introduced by the computer and OBS? I suppose there could be latency on both the HDMI output as well as the stream mix.

 

[koala]

The video on the hdmi output is instant. The same video that goes out to the streaming service has a latency of some seconds. Probably in the range of 10..30 seconds, depending on the streaming service. Some streaming services also offer especially low latency streams, this probably will get you in the range of about 5 seconds.