vMix
Live captions for vMix over NDI
Add realtime captions to any vMix production without a human captioner or a typist. LiveSubs transcribes a mic or any system audio and sends a transparent caption layer over NDI, so it drops in as an input and keys cleanly over your program.
Setup
How to add captions to vMix over NDI
Install and start LiveSubs
Run LiveSubs on the same PC or the same network as vMix, add minutes with a key, and pick the language you are captioning.
Choose your audio
Select your microphone, or a system-loopback device to caption program audio, a remote guest, or a playback source feeding the show.
Enable NDI, then add the input in vMix
Turn on NDI output in LiveSubs. In vMix, click Add Input, choose NDI, and pick the LiveSubs source from the list.
Position the caption title
Place the input in a title or overlay layer, size it to the lower third, and trigger it as an overlay over your program output. The frame is transparent, so only the caption text shows.
Why LiveSubs
Better than typed or CART workarounds
No typist, no CART booking
Captions are generated automatically in realtime, so you skip the cost and scheduling of a human captioner for routine shows and rehearsals.
Native NDI, no capture card
The caption layer arrives as a standard NDI source over your existing network, so there is no extra hardware and no SDI channel to burn.
Captions any audio vMix hears
Point it at a mic, a system-loopback device, or a remote caller, and it transcribes whatever is being spoken into the production.
Transparent and keyable
Output is a transparent NDI frame with outlined text, so it composites over your program feed like any other title or lower third.
Output
Fits how vMix already works
NDI input
Bring captions in as a native NDI input and treat them like any other source in your input list and overlay channels.
OSC text for GT titles
Prefer to drive your own graphics? Send the raw caption text over OSC into a title template or a downstream graphics tool.
Overlay channels
Assign the caption input to an overlay channel so operators can punch captions in and out live without touching the mix.
Pay per minute
A flat $0.04/min with no subscription, so a one-off broadcast or a weekly show only costs for the minutes you caption.
FAQ
Questions
How do I add live captions to vMix?
Run LiveSubs, pick your audio source and press Start, then enable NDI output. In vMix, click Add Input, choose NDI, and select the LiveSubs source. Place it in a title or overlay layer, size it to a lower third, and trigger it as an overlay over your program. You can also send the raw text over OSC if you drive your own titles.
Do I need a capture card or extra hardware for vMix NDI captions?
No. The caption layer is delivered as a native NDI source over your existing network, so there is nothing to plug in. As long as vMix can see the LiveSubs machine on the network, the input appears in the NDI list.
Can I caption program audio or a remote guest, not just a microphone?
Yes. Select a system-loopback device as the audio source and LiveSubs transcribes whatever is playing on that PC, including program audio, a video, or a caller on a call app. That covers remote guests and playback the same way it covers a local mic.
Is this better than typing captions manually or booking a CART writer?
For most productions, yes. Manual typing cannot keep pace with live speech, and a CART writer adds cost and scheduling. LiveSubs generates captions automatically in realtime and delivers them straight into vMix over NDI, so a producer can run it without extra staff.
Will the captions appear in my recording and stream?
Yes. Because the caption input is composited into your vMix program output, it is burned into whatever you record or stream out, exactly like your other titles and overlays.
Does it add latency to the production?
Captions are transcribed in the cloud in realtime and streamed to vMix continuously, so text keeps pace with the speaker. Any delay is the normal transcription latency, which sits comfortably within a live broadcast.
Related: Live captions for OBS · Caption system audio · Live captioning for events
Caption your next vMix show
Download LiveSubs, buy the minutes you need, and route realtime captions into vMix over NDI.