WebRTC congestion control (#26)

* Add congestion control

* Improve stream matching, add manual stream selection, add metrics

* Use a ticker for bitrate estimation and make bandwidth drops switch to lower streams more aggressively

* Missing signal response, fix video auto bug

* Remove redundant mutex

* Bitrate history queue

* Get bitrate fn support h264 & float64

---------

Co-authored-by: Aleksandar Sukovic <aleksandar.sukovic@gmail.com>
This commit is contained in:
Miroslav Šedivý
2023-02-06 19:45:51 +01:00
committed by GitHub
parent e80ae8019e
commit 2364facd60
15 changed files with 738 additions and 222 deletions

View File

@ -9,6 +9,8 @@ import (
"github.com/pion/ice/v2"
"github.com/pion/interceptor"
"github.com/pion/interceptor/pkg/cc"
"github.com/pion/interceptor/pkg/gcc"
"github.com/pion/rtcp"
"github.com/pion/webrtc/v3"
"github.com/rs/zerolog"
@ -35,6 +37,9 @@ const keepAliveInterval = 2 * time.Second
// send a PLI on an interval so that the publisher is pushing a keyframe every rtcpPLIInterval
const rtcpPLIInterval = 3 * time.Second
// how often we check the bitrate of each client. Default is 250ms
const bitrateCheckInterval = 250 * time.Millisecond
func New(desktop types.DesktopManager, capture types.CaptureManager, config *config.WebRTC) *WebRTCManagerCtx {
configuration := webrtc.Configuration{
SDPSemantics: webrtc.SDPSemanticsUnifiedPlanWithFallback,
@ -153,12 +158,12 @@ func (manager *WebRTCManagerCtx) ICEServers() []types.ICEServer {
return manager.config.ICEServers
}
func (manager *WebRTCManagerCtx) newPeerConnection(codecs []codec.RTPCodec, logger zerolog.Logger) (*webrtc.PeerConnection, error) {
func (manager *WebRTCManagerCtx) newPeerConnection(bitrate int, codecs []codec.RTPCodec, logger zerolog.Logger) (*webrtc.PeerConnection, cc.BandwidthEstimator, error) {
// create media engine
engine := &webrtc.MediaEngine{}
for _, codec := range codecs {
if err := codec.Register(engine); err != nil {
return nil, err
return nil, nil, err
}
}
@ -205,8 +210,29 @@ func (manager *WebRTCManagerCtx) newPeerConnection(codecs []codec.RTPCodec, logg
// create interceptor registry
registry := &interceptor.Registry{}
congestionController, err := cc.NewInterceptor(func() (cc.BandwidthEstimator, error) {
if bitrate == 0 {
bitrate = 1000000
}
return gcc.NewSendSideBWE(gcc.SendSideBWEInitialBitrate(bitrate))
})
if err != nil {
return nil, nil, err
}
estimatorChan := make(chan cc.BandwidthEstimator, 1)
congestionController.OnNewPeerConnection(func(id string, estimator cc.BandwidthEstimator) {
estimatorChan <- estimator
})
registry.Add(congestionController)
if err = webrtc.ConfigureTWCCHeaderExtensionSender(engine, registry); err != nil {
return nil, nil, err
}
if err := webrtc.RegisterDefaultInterceptors(engine, registry); err != nil {
return nil, err
return nil, nil, err
}
// create new API
@ -217,10 +243,12 @@ func (manager *WebRTCManagerCtx) newPeerConnection(codecs []codec.RTPCodec, logg
)
// create new peer connection
return api.NewPeerConnection(manager.webrtcConfiguration)
configuration := manager.webrtcConfiguration
connection, err := api.NewPeerConnection(configuration)
return connection, <-estimatorChan, err
}
func (manager *WebRTCManagerCtx) CreatePeer(session types.Session, bitrate int) (*webrtc.SessionDescription, error) {
func (manager *WebRTCManagerCtx) CreatePeer(session types.Session, bitrate int, videoAuto bool) (*webrtc.SessionDescription, error) {
id := atomic.AddInt32(&manager.peerId, 1)
manager.metrics.NewConnection(session)
@ -236,7 +264,7 @@ func (manager *WebRTCManagerCtx) CreatePeer(session types.Session, bitrate int)
video := manager.capture.Video()
videoCodec := video.Codec()
connection, err := manager.newPeerConnection([]codec.RTPCodec{
connection, estimator, err := manager.newPeerConnection(bitrate, []codec.RTPCodec{
audioCodec,
videoCodec,
}, logger)
@ -244,6 +272,10 @@ func (manager *WebRTCManagerCtx) CreatePeer(session types.Session, bitrate int)
return nil, err
}
if bitrate == 0 {
bitrate = estimator.GetTargetBitrate()
}
// asynchronously send local ICE Candidates
if manager.config.ICETrickle {
connection.OnICECandidate(func(candidate *webrtc.ICECandidate) {
@ -268,31 +300,117 @@ func (manager *WebRTCManagerCtx) CreatePeer(session types.Session, bitrate int)
}
// set stream for audio track
err = audioTrack.SetStream(audio)
_, err = audioTrack.SetStream(audio)
if err != nil {
return nil, err
}
// video track
videoTrack, err := NewTrack(logger, videoCodec, connection)
videoTrack, err := NewTrack(logger, videoCodec, connection, WithVideoAuto(videoAuto))
if err != nil {
return nil, err
}
// let video stream bucket manager handle stream subscriptions
err = video.SetReceiver(videoTrack)
if err != nil {
return nil, err
video.SetReceiver(videoTrack)
changeVideoFromBitrate := func(peerBitrate int) {
// when switching from manual to auto bitrate estimation, in case the estimator is
// idle (lastBitrate > maxBitrate), we want to go back to the previous estimated bitrate
if peerBitrate == 0 {
peerBitrate = estimator.GetTargetBitrate()
manager.logger.Debug().
Int("peer_bitrate", peerBitrate).
Msg("evaluated bitrate")
}
ok, err := videoTrack.SetBitrate(peerBitrate)
if err != nil {
logger.Error().Err(err).
Int("peer_bitrate", peerBitrate).
Msg("unable to set video bitrate")
return
}
if !ok {
return
}
videoID := videoTrack.stream.ID()
bitrate := videoTrack.stream.Bitrate()
manager.metrics.SetVideoID(session, videoID)
manager.logger.Debug().
Int("peer_bitrate", peerBitrate).
Int("video_bitrate", bitrate).
Str("video_id", videoID).
Msg("peer bitrate triggered video stream change")
go session.Send(
event.SIGNAL_VIDEO,
message.SignalVideo{
Video: videoID,
Bitrate: bitrate,
VideoAuto: videoTrack.VideoAuto(),
})
}
changeVideoFromID := func(videoID string) (bitrate int) {
changed, err := videoTrack.SetVideoID(videoID)
if err != nil {
logger.Error().Err(err).
Str("video_id", videoID).
Msg("unable to set video stream")
return
}
if !changed {
return
}
bitrate = videoTrack.stream.Bitrate()
manager.logger.Debug().
Str("video_id", videoID).
Int("video_bitrate", bitrate).
Msg("peer video id triggered video stream change")
go session.Send(
event.SIGNAL_VIDEO,
message.SignalVideo{
Video: videoID,
Bitrate: bitrate,
VideoAuto: videoTrack.VideoAuto(),
})
return
}
manager.logger.Info().
Int("target_bitrate", bitrate).
Msg("estimated initial peer bitrate")
// set initial video bitrate
if err = videoTrack.SetBitrate(bitrate); err != nil {
return nil, err
}
changeVideoFromBitrate(bitrate)
videoID := videoTrack.stream.ID()
manager.metrics.SetVideoID(session, videoID)
// use a ticker to get current client target bitrate
go func() {
ticker := time.NewTicker(bitrateCheckInterval)
defer ticker.Stop()
for range ticker.C {
targetBitrate := estimator.GetTargetBitrate()
manager.metrics.SetReceiverEstimatedMaximumBitrate(session, float64(targetBitrate))
if connection.ConnectionState() == webrtc.PeerConnectionStateClosed {
break
}
if !videoTrack.VideoAuto() {
continue
}
changeVideoFromBitrate(targetBitrate)
}
}()
// data channel
@ -302,27 +420,20 @@ func (manager *WebRTCManagerCtx) CreatePeer(session types.Session, bitrate int)
}
peer := &WebRTCPeerCtx{
logger: logger,
connection: connection,
dataChannel: dataChannel,
changeVideo: func(bitrate int) error {
if err := videoTrack.SetBitrate(bitrate); err != nil {
return err
}
videoID := videoTrack.stream.ID()
manager.metrics.SetVideoID(session, videoID)
return nil
},
logger: logger,
connection: connection,
dataChannel: dataChannel,
changeVideoFromBitrate: changeVideoFromBitrate,
changeVideoFromID: changeVideoFromID,
// TODO: Refactor.
videoId: func() string {
return videoTrack.stream.ID()
},
videoId: videoTrack.stream.ID,
setPaused: func(isPaused bool) {
videoTrack.SetPaused(isPaused)
audioTrack.SetPaused(isPaused)
},
iceTrickle: manager.config.ICETrickle,
iceTrickle: manager.config.ICETrickle,
setVideoAuto: videoTrack.SetVideoAuto,
getVideoAuto: videoTrack.VideoAuto,
}
connection.OnTrack(func(track *webrtc.TrackRemote, receiver *webrtc.RTPReceiver) {
@ -515,11 +626,7 @@ func (manager *WebRTCManagerCtx) CreatePeer(session types.Session, bitrate int)
})
videoTrack.OnRTCP(func(p rtcp.Packet) {
switch rtcpPacket := p.(type) {
case *rtcp.ReceiverEstimatedMaximumBitrate: // TODO: Deprecated.
manager.metrics.SetReceiverEstimatedMaximumBitrate(session, rtcpPacket.Bitrate)
case *rtcp.ReceiverReport:
if rtcpPacket, ok := p.(*rtcp.ReceiverReport); ok {
l := len(rtcpPacket.Reports)
if l > 0 {
// use only last report