Browser ignore google congestion controller max bitrate

[asticode]

Hey guys,

I'm using the google congestion controller like this :

i := &interceptor.Registry{}

ccf, _ := cc.NewInterceptor(func() (cc.BandwidthEstimator, error) {
	return gcc.NewSendSideBWE(
		gcc.SendSideBWEInitialBitrate(int(minBitrate)),
		gcc.SendSideBWEMaxBitrate(int(maxBitrate)),
		gcc.SendSideBWEMinBitrate(int(minBitrate)),
	)
})

i.Add(ccf)

webrtc.ConfigureTWCCHeaderExtensionSender(m, i)

webrtc.RegisterDefaultInterceptors(m, i)

api := webrtc.NewAPI(
	webrtc.WithInterceptorRegistry(i),
	webrtc.WithMediaEngine(m),
	webrtc.WithSettingEngine(se),
)

I can see that it's making a difference since the browser sent bitrate is way bigger.

Unfortunately, whatever value I set in maxBitrate, the browser (Chrome and Firefox) always send around 2,5Mbps (the same is happening if maxBitrate is smaller or bigger than 2,5Mbps).

Is there something I'm doing wrong? Or is there anything else I need to do?

Cheers
Quentin

[silently]

Hello,

This is a late reply but I think what improved the situation with the browser bitrate is enabling TWCC.

NewSendSideBWE's primary effect is to create an estimator like in this example, then you can use the estimator to adapt what is sent to the other side of pion.