snapshot of https://github.com/livekit/livekit.git @ 08c5433449c106943231037d0b892895f6e92d3b (2026-09-15)

pkg/rtc/dynacast/dynacastqualityvideo.go

@@ -0,0 +1,249 @@
+// Copyright 2023 LiveKit, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package dynacast
+
+import (
+	"sync"
+	"time"
+
+	"github.com/livekit/protocol/codecs/mime"
+	"github.com/livekit/protocol/livekit"
+	"github.com/livekit/protocol/logger"
+)
+
+var _ dynacastQuality = (*dynacastQualityVideo)(nil)
+
+const (
+	initialQualityUpdateWait = 10 * time.Second
+)
+
+type dynacastQualityVideoParams struct {
+	MimeType mime.MimeType
+	Listener dynacastQualityListener
+	Logger   logger.Logger
+}
+
+// dynacastQualityVideo manages max subscribed quality of a single receiver of a media track
+type dynacastQualityVideo struct {
+	params dynacastQualityVideoParams
+
+	// quality level enable/disable
+	lock                     sync.RWMutex
+	initialized              bool
+	maxSubscriberQuality     map[livekit.ParticipantID]livekit.VideoQuality
+	maxSubscriberNodeQuality map[livekit.NodeID]livekit.VideoQuality
+	maxSubscribedQuality     livekit.VideoQuality
+	maxQualityTimer          *time.Timer
+	regressTo                dynacastQuality
+
+	dynacastQualityNull
+}
+
+func newDynacastQualityVideo(params dynacastQualityVideoParams) dynacastQuality {
+	return &dynacastQualityVideo{
+		params:                   params,
+		maxSubscriberQuality:     make(map[livekit.ParticipantID]livekit.VideoQuality),
+		maxSubscriberNodeQuality: make(map[livekit.NodeID]livekit.VideoQuality),
+	}
+}
+
+func (d *dynacastQualityVideo) Start() {
+	d.reset()
+}
+
+func (d *dynacastQualityVideo) Restart() {
+	d.reset()
+}
+
+func (d *dynacastQualityVideo) Stop() {
+	d.stopMaxQualityTimer()
+}
+
+func (d *dynacastQualityVideo) NotifySubscriberMaxQuality(subscriberID livekit.ParticipantID, quality livekit.VideoQuality) {
+	d.params.Logger.Debugw(
+		"setting subscriber max quality",
+		"mime", d.params.MimeType,
+		"subscriberID", subscriberID,
+		"quality", quality.String(),
+	)
+
+	d.lock.Lock()
+	if r := d.regressTo; r != nil {
+		d.lock.Unlock()
+		r.NotifySubscriberMaxQuality(subscriberID, quality)
+		return
+	}
+
+	if quality == livekit.VideoQuality_OFF {
+		delete(d.maxSubscriberQuality, subscriberID)
+	} else {
+		d.maxSubscriberQuality[subscriberID] = quality
+	}
+	d.lock.Unlock()
+
+	d.updateQualityChange(false)
+}
+
+func (d *dynacastQualityVideo) NotifySubscriberNodeMaxQuality(nodeID livekit.NodeID, quality livekit.VideoQuality) {
+	d.params.Logger.Debugw(
+		"setting subscriber node max quality",
+		"mime", d.params.MimeType,
+		"subscriberNodeID", nodeID,
+		"quality", quality.String(),
+	)
+
+	d.lock.Lock()
+	if r := d.regressTo; r != nil {
+		// the downstream node will synthesize correct quality notify (its dynacast manager has codec regression), just ignore it
+		d.params.Logger.Debugw(
+			"ignoring node quality change, regressed to another dynacast quality",
+			"mime", d.params.MimeType,
+			"regressedMime", d.regressTo.Mime(),
+		)
+		d.lock.Unlock()
+		return
+	}
+
+	if quality == livekit.VideoQuality_OFF {
+		delete(d.maxSubscriberNodeQuality, nodeID)
+	} else {
+		d.maxSubscriberNodeQuality[nodeID] = quality
+	}
+	d.lock.Unlock()
+
+	d.updateQualityChange(false)
+}
+
+func (d *dynacastQualityVideo) ClearSubscriberNodes() {
+	d.lock.Lock()
+	d.maxSubscriberNodeQuality = make(map[livekit.NodeID]livekit.VideoQuality)
+	d.lock.Unlock()
+
+	d.updateQualityChange(false)
+}
+
+func (d *dynacastQualityVideo) Mime() mime.MimeType {
+	return d.params.MimeType
+}
+
+func (d *dynacastQualityVideo) RegressTo(other dynacastQuality) {
+	d.lock.Lock()
+	d.regressTo = other
+	maxSubscriberQuality := d.maxSubscriberQuality
+	maxSubscriberNodeQuality := d.maxSubscriberNodeQuality
+	d.maxSubscriberQuality = make(map[livekit.ParticipantID]livekit.VideoQuality)
+	d.maxSubscriberNodeQuality = make(map[livekit.NodeID]livekit.VideoQuality)
+	d.lock.Unlock()
+
+	other.Replace(maxSubscriberQuality, maxSubscriberNodeQuality)
+}
+
+func (d *dynacastQualityVideo) Replace(
+	maxSubscriberQuality map[livekit.ParticipantID]livekit.VideoQuality,
+	maxSubscriberNodeQuality map[livekit.NodeID]livekit.VideoQuality,
+) {
+	d.lock.Lock()
+	for subID, quality := range maxSubscriberQuality {
+		if oldQuality, ok := d.maxSubscriberQuality[subID]; ok {
+			// no QUALITY_OFF in the map
+			if quality > oldQuality {
+				d.maxSubscriberQuality[subID] = quality
+			}
+		} else {
+			d.maxSubscriberQuality[subID] = quality
+		}
+	}
+
+	for nodeID, quality := range maxSubscriberNodeQuality {
+		if oldQuality, ok := d.maxSubscriberNodeQuality[nodeID]; ok {
+			// no QUALITY_OFF in the map
+			if quality > oldQuality {
+				d.maxSubscriberNodeQuality[nodeID] = quality
+			}
+		} else {
+			d.maxSubscriberNodeQuality[nodeID] = quality
+		}
+	}
+	d.lock.Unlock()
+
+	d.Restart()
+}
+
+func (d *dynacastQualityVideo) reset() {
+	d.lock.Lock()
+	d.initialized = false
+	d.lock.Unlock()
+
+	d.startMaxQualityTimer()
+}
+
+func (d *dynacastQualityVideo) updateQualityChange(force bool) {
+	d.lock.Lock()
+	maxSubscribedQuality := livekit.VideoQuality_OFF
+	for _, subQuality := range d.maxSubscriberQuality {
+		if maxSubscribedQuality == livekit.VideoQuality_OFF || (subQuality != livekit.VideoQuality_OFF && subQuality > maxSubscribedQuality) {
+			maxSubscribedQuality = subQuality
+		}
+	}
+	for _, nodeQuality := range d.maxSubscriberNodeQuality {
+		if maxSubscribedQuality == livekit.VideoQuality_OFF || (nodeQuality != livekit.VideoQuality_OFF && nodeQuality > maxSubscribedQuality) {
+			maxSubscribedQuality = nodeQuality
+		}
+	}
+
+	if maxSubscribedQuality == d.maxSubscribedQuality && d.initialized && !force {
+		d.lock.Unlock()
+		return
+	}
+
+	d.initialized = true
+	d.maxSubscribedQuality = maxSubscribedQuality
+	d.params.Logger.Debugw(
+		"notifying quality change",
+		"mime", d.params.MimeType,
+		"maxSubscriberQuality", d.maxSubscriberQuality,
+		"maxSubscriberNodeQuality", d.maxSubscriberNodeQuality,
+		"maxSubscribedQuality", d.maxSubscribedQuality,
+		"force", force,
+	)
+	d.lock.Unlock()
+
+	d.params.Listener.OnUpdateMaxQualityForMime(d.params.MimeType, maxSubscribedQuality)
+}
+
+func (d *dynacastQualityVideo) startMaxQualityTimer() {
+	d.lock.Lock()
+	defer d.lock.Unlock()
+
+	if d.maxQualityTimer != nil {
+		d.maxQualityTimer.Stop()
+		d.maxQualityTimer = nil
+	}
+
+	d.maxQualityTimer = time.AfterFunc(initialQualityUpdateWait, func() {
+		d.stopMaxQualityTimer()
+		d.updateQualityChange(true)
+	})
+}
+
+func (d *dynacastQualityVideo) stopMaxQualityTimer() {
+	d.lock.Lock()
+	defer d.lock.Unlock()
+
+	if d.maxQualityTimer != nil {
+		d.maxQualityTimer.Stop()
+		d.maxQualityTimer = nil
+	}
+}