Enhanced Bandwidth Estimation for WebRTC ABR

[getroot]

OvenMediaEngine previously used REMB for ABR streaming over WebRTC.
While REMB works in many cases, it may underestimate available bandwidth in situations such as static or low motion video, which can lead to suboptimal rendition selection.

We have implemented a new bandwidth estimation method for ABR based on Transport-CC feedback.
Transport-CC provides more detailed transport level feedback, allowing OvenMediaEngine to estimate available bandwidth more accurately and deliver the most appropriate rendition to each player.

You can enable it as follows:

<Publishers>
    <WebRTC>
        <Timeout>30000</Timeout>
        <BandwidthEstimation>TransportCC</BandwidthEstimation> <!-- REMB | TransportCC | ALL -->
    </WebRTC>
</Publishers>

The BandwidthEstimation option supports the following values:

• REMB: Uses the legacy REMB based estimation.
• TransportCC: Uses the new Transport-CC based estimation.
• ALL: Includes both REMB and Transport-CC in the SDP offer, allowing the player to choose. This is the default.

Since ALL is the default and most modern browsers prefer Transport-CC, the improved bandwidth estimation works out of the box without any configuration changes.

This feature is available now in the master branch, so you can test it immediately.
If you encounter any issues or have suggestions for improvement, please feel free to share your feedback.

Thank you.