Hello,

I'd very much like to have a VST / AudioUnit plugin that I could insert on the master bus of my DAW which would allow me to send externally generated / mixed audio to vMix over NDI.

I work as a sound engineer and occasionally I run across the issue of needing to do two separate audio mixes for an event: one for the venue FOH speakers and one for the live stream. Mixing audio for a live event is quite different from mixing audio for a live stream; while I could technically just stream whatever I'm sending to the FOH speakers, it would usually end up sounding all kinds of weird in the stream - for example the drums are usually loud enough that I don't really need to reinforce them through the FOH, so in the stream there would be very little to no drums, compared to e.g. the vocals, of which there would be too much. One solution that I'm currently experimenting with is using the stage mixer as an audio interface during the show, so that while I can mix audio for the FOH using the stage mixer directly, another engineer can do a separate mix in a DAW on a computer which uses the mixer just as an interface. But then I have to get the audio mix from the DAW into vMix somehow. I could in theory run a cable from one of the mixer's outputs to the computer running vMix, but then I need another audio interface for this computer and I have to sacrifice two precious AUX outputs at the mixer to get the analog audio out. Plus there are all sorts of other issues stemming from ground loops, long cable runs etc.

Having a plugin that I could insert on the master bus of the DAW would greatly simplify this setup. I've had a look at the NDI SDK and even though I can make sense of the basics, my programming expertise is websites, so C++ is really not my area; but it does seem that for someone who knows what they're doing an NDI source plugin should be a piece of cake (as in literally ~10 lines of code after all the libraries are imported). I can imagine it would enable a host of other workflows which are currently impossible / hard to do, all in one fell swoop.

Thanks for reading this :-)
Dan

Well, the NDI SDK includes some example code and there is an example showing how to create an NDI source; IIRC there's like one function call to initialise the NDI source object and another function which you call in a loop to send buffers of audio data. I haven't really studied VST or AU SDKs, but I imagine there would also be some small part to initialise a plugin and then there would be a function which the host software would call periodically to process a buffer of audio data.. so within this function you'd call the NDI function and pass it the buffer the plugin received to process, and return the buffer back so that from the point of view of the DAW the plugin just passes audio through unchanged (so that you can e.g. hear it in headphones). And while most VST / AU plugins have a GUI and that's probably a whole different beast, this plugin wouldn't really need any parameters, so it wouldn't need a GUI, which as far as I can tell is perfectly okay for the DAW.. So a couple of lines of initialisation and a couple of lines in the main function. Might be more than 10, but not by much :-)

I’m also under this quest! Would be very handy to have.

It already exists on windows because under vectar plus there is a VST plugin, that acts as an audio source:
https://www.vizrt.com/en/products/viz-vectar-plus

The only work workaround I have found but not tested is this set of tools:
http://ndi.lofas.se/

Hope this illustrates or adds some light.