According to the post of @gpolitis as the following
"The way “basic” simulcast works in jitsi-meet/jitsi-videobridge is based on the following two rules:
- an endpoint sends 1 low quality stream and, if it has enough outgoing bandwidth, 1 high quality stream.
- an endpoint receives low quality video except for the selected endpoint for which it receives high quality IF the selected endpoint is actually streaming high quality, otherwise it will receive low quality for that endpoint too.
With adaptive simulcast the 2nd rule is enhanced like this:
- an endpoint receives low quality video except for the selected endpoint for which it receives high quality IF the selected endpoint is actually streaming high quality AND if the receiver has enough incoming bandwidth, otherwise it will receive low quality for that endpoint too."
I can understand that the sender will always transmit TWO streams simultaneously with low and high bandwidth if it has enough bandwidth. So it doesnot work in the same manner as in OTT with adaptive stream: sender will send only ONE stream with the bitrate requested (and better fit to current bandwidth of the receiver) by the receiver ?
Then can I know which low and high bandwidth will be transmitted? The structure kSimulcastFormats in file simulcass.ss has several resolution, I wonder which ones are the selected two.
@gpolitis also mentioned the selected endpoint to get the high quality. How can I specify that endpoint? And again which resolution the endpoint will choose to send out.
Also concerning the bandwidth adjustment, jitsi no longer sends out video signal if the bandwidth is too low. Where can we set that threshold please?And the threshold is calculated based on the BW of the transmitter or the receiver
Many thanks in advance for your guide