If you are already running the latest version of vMix, you will only need to follow the next few steps, in order to take full advantage of a multibitrate output:
1. From vMix's main window, click on ⚙️ Stream settings:

2. It is assumed that you've already created a live stream player and obtained the RTMP address and key - see how. Then you have added them to vMix Streaming Settings -> [ 1 ]:

3. Set the main bitrate and resolution that you wish to run your stream at, by either choosing from the Quality presets, or creating a custom one via pressing the adjacent ⚙️ Gear cog. We recommend 4000kbps for 1080p (for other resolutions see the sheet below). In any case, it shouldn't exceed 5000kbps and 1920x1080. Always use H264 for video codec and AAC for audio codec.
Recommended video bitrates:
Quality | Resolution | Recommended Video Bitrate (kbps) |
1080p (Full HD) | 1920x1080 | 3500-4000 |
720p (HD) | 1280x720 | 1500-2000 |
480p (Medium) | 854x480 | 1000-1200 |
360p (Low) | 640x360 | 600-800 |
240p (Very Low) | 426x240 | 200-400 |
Recommended audio bitrates:
Quality | Recommended Audio Bitrate (kbps) |
Poor | 64 |
Low | 96 |
Medium | 128 |
High | 160 |
High Quality | 192 |
4. Click on the second stream [ 2 ] and choose Custom RTMP Server as a Destination, remove the tick in front of Use Stream 1 Quality, choose a lower resolution and use the same RTMP Server and RTMP Key as before, ONLY this time add 2 at the end of the RTMP Key to signify it's the second available resolution for your stream:

5. Do the same for stream number [ 3 ] and use a lower resolution than the previous two. Add 3 at the end of the RTMP Key to set it as the third available resolution. Click Save and Close.

6. Start multibitrate streaming by clicking the Stream button. It should turn red which indicates your streams are being pushed to the server.

8. Allow a minute to pass to ensure all streams are equally ingested onto our servers, before opening your Live Studio and start Broadcasting from your StreamingVideoProvider account.

9. You will see a gear cog in both Preview panels in your Live studio upon a successful execution of all the steps in this guide, from where you and your viewers will be able to switch between resolutions. The default setting for every viewer is Auto, unless a specific resolution is selected.

Note: If for some reason, you don't see the gear cog, please stop the broadcast and exit the Live Studio, and after another 30 seconds - open it and Start Broadcasting again. If you still don't see it, double-check your settings from steps 2 to 5.
When viewers with poor internet connections are watching your livestream, every time their download speed deteriorates, their player will switch onto a lower bitrate resolution instead of showing a buffering wheel, which would ensure a smoother experience.
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