RTMP MBR to WebRTC Simulcast
Dolby.io Real-time Streaming enable users to stream RTMP MBR (Multi-Bitrate) for delivery via WebRTC Simulcast. This gives the streamer the ability to use their RTMP encoder to control their RTMP multi-bitrate renditions, and provide "adaptive bitrate" delivery in the Millicast web player using WebRTC Simulcast:

Getting Started
Download the latest version of OBS.
After you install the OBS, you can install the multiple RTMP plug-in for OBS.
obs-multi-rtmp is a plugin for streaming multiple RTMP streams concurrently.
This plugin can share encoders with the main output of OBS to save CPU power. It can also use standalone encoders with the basic configuration (bitrate).
How to Install the Plugin in Windows
- Download the latest release from OBS-Multi-RTMP.
- Unzip the zip file and extract it into the OBS folder.
OBS Studio C:\Program Files\obs studio
Millicast OBS default location. C:\Program Files\OBS WebRTC (64bit)\obs-plugins

You should see the following obs-multi-rtmp.dll in your plugins folder.

Once you have the obs-multi-rtmp.dll in your C:\Program Files\OBS WebRTC (64bit)\obs-plugins folder you can start the OBS-WebRTC version.
After you have installed the plugin, open OBS-WebRTC and you will see a new "Multiple Output" option in the Docks Menu. You can open the panel by selecting Menu > Docks -> Multiple Output

Adding Stream Targets
Enable multisource on your publish token
Make sure you have enabled multisource on your publish token. For more information check Managing your tokens
Click "Add New Target" on the Multiple output panel:

Input the RTMP details, including the RTMP Key following this format:
{StreamName}?token={Token}&sourceId={number of source}&simulcastId
You can find the StreamName and Token in the Dolby.io dashboard. The sourceId must be numbers 1-3 with simulcastId enabled.
Example:
livename?token=UIGfw2aMkC6AVssda2dacSzMkxGFtLOk&sourceId=1&simulcastId
Here is example using 3 bitrates (1080p, 720p, 360p) as inputs using the obs-multi-rtmp plugin:
Name | 1080p |
RTMP Server | rtmp://live-rtmp-pub.millicast.com:1935/v2/pub/ |
RTMP Key | {StreamName}?token={Token}&sourceId=1&simulcastId |
Encoder | x264 or nvenc |
Resolution | 1920x1080 |
Bitrate | 6000kbps |
Keyframe | 2 |
BFrames | 0 |
Name | 720p |
RTMP Server | rtmp://live-rtmp-pub.millicast.com:1935/v2/pub/ |
RTMP Key | {StreamName}?token={Token}&sourceId=2&simulcastId&videoOnly |
Encoder | x264 or nvenc |
Resolution | 1280x720 |
Bitrate | 2000kbps |
Keyframe | 2 |
BFrames | 0 |
Name | 360p |
RTMP Server | rtmp://live-rtmp-pub.millicast.com:1935/v2/pub/ |
RTMP Key | {StreamName}?token={Token}&sourceId=3&simulcastId&videoOnly |
Encoder | x264 or nvenc |
Resolution | 640x360 |
Bitrate | 500kbps |
Keyframe | 2 |
BFrames | 0 |
Start Publishing
Click the "Start" button for each target.

Please note that may you need to click "Start Streaming" in OBS to update the current configuration, then click "Stop Streaming" and return to the "Multiple output" panel. When you click "Start Streaming" again the config will be updated and the RTMP MBR renditions will stream to Dolby.io Real-time Streaming services.
The Millicast player will support the RTMP MBR sources using WebRTC Simulcast in the web browser:

Updated 6 months ago