Broadcasting with vMix to Millicast MBR and NDI

About VMix

vMix encoder is a software vision mixer available for the Windows operating system. Like most vision mixing software, it allows users to switch inputs, mix audio, record outputs, and live stream cameras, videos files, audio, and more, in resolutions of up to 4K. You can download vMix here.

Getting Started

From your Dolby.io dashboard you will need your RTMP publishing paths.
On your vMix select the stream COG and enter the following for you publishing destination.

Destination: Custom RTMP Server
URL: RTMP: rtmp://live-rtmp-pub.millicast.com:1935/v2/pub/
Stream Name or Key: StreamName: kwayjfek?token=9d74883d694198da51e3be52631111111222222222233333
Quality: Your best settings.
Application: FFMPEG

Select the quality COG and make sure baseline profile is selected. Stutter may occur if set to main or high.

Additional settings can be adjusted at this time based on your preferences and network capacity.
Save your publishing profile and you are ready to start publishing with vMix.

vMix Multi Bitrate to WebRTC Simulcast

With vMix you have the ability to send your live stream to 3 destinations (Simulcast). This feature combined with Dolby.io Real-time Streaming multisource capabilities allows you to send 3 renditions of your stream. This allows viewers with limited bandwidth to receive the lower renditions created in your vMix settings.

Getting Started MBR


Enable multisource on your publish token

Make sure you have enabled multisource on your publish token. For more information check Managing your tokens

Keep in mind that you will be sending 3 streams simultaneously and adequate bandwidth should be determined. You can also send just 2 renditions of your stream if you are limited with bandwidth. Quality shown here can be adjusted as needed.

Destination 1

Destination 2

Destination 3


Here is example using 3 bitrates (1080p, 720p, 360p) .

RTMP Serverrtmp://live-rtmp-pub.millicast.com:1935/v2/pub/
RTMP Key{StreamName}?token={Token}&sourceId=1&simulcastId
Bitrate6000kbps or as shown 4500kbps
RTMP Serverrtmp://live-rtmp-pub.millicast.com:1935/v2/pub/
RTMP Key{StreamName}?token={Token}&sourceId=2&simulcastId&videoOnly
Bitrate2000kbps or as shown 1500kbps
RTMP Serverrtmp://live-rtmp-pub.millicast.com:1935/v2/pub/
RTMP Key{StreamName}?token={Token}&sourceId=3&simulcastId&videoOnly

On vMix click start all streams . Launch your Millicast viewer and you will now see in the COG the available renditions. The Millicast player supports the RTMP MBR sources using WebRTC Simulcast in the web browser:

Optional encoders can be used to accomplish the same MBR features such as OBS or Wirecast. Additional documentation can be found here.

NDI with vMix

vMix can also be set as an NDI source allowing you to use the Millicast publisher or Millicast OBS Web RTC version. This can give you the flexibility to use vMix as your switcher with Millicast OBS Web RTC or Web Publisher.

To set vMix as an NDI source select the external source COG.

Note: It is recommended you use hardwired connections for you NDI sources or dedicated QoS networking enabled.
40 Mpbs plus of network may used from NDI sources if used. Congestion and limited bandwidth can create issues with audio or video quality.