Videobridge automatic bandwidth too low

I’m struggling to get a decent video quality when going through the videobridge (2-participant p2p works fine).

I understand that the VB has some kind of bandwidth estimation and reduces video quality if necessary. It seems on my setup it grossly underestimates the available bandwidth.

For example on a 3-participant meeting:

  • each cleints seems to send up 720p or 640p video at roughtly 3mbit/s.
  • videobridge sends down 320p videos, roughly 300kbit/s each, producing dowstream network load on clients of about 600-700kbit/s and 2mbit/s on server.

Each of the clients can at least do 50mbit/s downstream and the server can do 50mbit/s upstream. Videobridge uses 20% CPU.

I tried using these settings

org.jitsi.videobridge.ONSTAGE_PREFERRED_HEIGHT=1080
org.jitsi.videobridge.TRUST_BWE=true
org.jitsi.impl.neomedia.rtp.sendsidebandwidthestimation.BandwidthEstimatorImpl.START_BITRATE_BPS=2500000
org.jitsi.videobridge.ENABLE_SVC=true

but it didn’t help, making the video quality rather worse than better.

Any ideas how to fix that?

Are you seeing this when participants are on stage or it is when using tile view?
When you are in tile view the UI estimates the thumbs sizes and instructs jvb for that so it does not send HD for those thumbs.

It’s even when on stage. The resolution fluctuates a lot, changes every 10s or so, but I rarely get the full resolution, and only for some participants. But I can do p2p with any of the participants and get max camera resolution without issues.

If you experiment with same participants on meet.jit.si do you see the same?

Can’t try that right now, but with a quick loopback test with 2 browser windows, it looks like meet.jit.si allows me less bandwidth in the first place, so it looks even worse. Got 360p on meet.jit.si vs. 540p on my own server. Camera can do 720p.

Two windows on meet.jit.si should be p2p.

I intentionally used Firefox to prevent that.