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

pkg/rtc/dynacast/dynacastmanager_test.go

@@ -0,0 +1,523 @@
+// 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 (
+	"slices"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/livekit/livekit-server/pkg/rtc/types"
+	"github.com/livekit/protocol/codecs/mime"
+	"github.com/livekit/protocol/livekit"
+)
+
+type testDynacastManagerListener struct {
+	onSubscribedMaxQualityChange func(subscribedQualties []*livekit.SubscribedCodec)
+	onSubscribedAudioCodecChange func(subscribedCodecs []*livekit.SubscribedAudioCodec)
+}
+
+func (t *testDynacastManagerListener) OnDynacastSubscribedMaxQualityChange(
+	subscribedQualities []*livekit.SubscribedCodec,
+	_maxSubscribedQualities []types.SubscribedCodecQuality,
+) {
+	t.onSubscribedMaxQualityChange(subscribedQualities)
+}
+
+func (t *testDynacastManagerListener) OnDynacastSubscribedAudioCodecChange(
+	codecs []*livekit.SubscribedAudioCodec,
+) {
+	t.onSubscribedAudioCodecChange(codecs)
+}
+
+func TestSubscribedMaxQuality(t *testing.T) {
+	t.Run("subscribers muted", func(t *testing.T) {
+		var lock sync.Mutex
+		actualSubscribedQualities := make([]*livekit.SubscribedCodec, 0)
+
+		dm := NewDynacastManagerVideo(DynacastManagerVideoParams{
+			Listener: &testDynacastManagerListener{
+				onSubscribedMaxQualityChange: func(subscribedQualities []*livekit.SubscribedCodec) {
+					lock.Lock()
+					actualSubscribedQualities = subscribedQualities
+					lock.Unlock()
+				},
+			},
+		})
+
+		dm.NotifySubscriberMaxQuality("s1", mime.MimeTypeVP8, livekit.VideoQuality_HIGH)
+		dm.NotifySubscriberMaxQuality("s2", mime.MimeTypeAV1, livekit.VideoQuality_HIGH)
+
+		// mute all subscribers of vp8
+		dm.NotifySubscriberMaxQuality("s1", mime.MimeTypeVP8, livekit.VideoQuality_OFF)
+
+		expectedSubscribedQualities := []*livekit.SubscribedCodec{
+			{
+				Codec: mime.MimeTypeVP8.String(),
+				Qualities: []*livekit.SubscribedQuality{
+					{Quality: livekit.VideoQuality_LOW, Enabled: false},
+					{Quality: livekit.VideoQuality_MEDIUM, Enabled: false},
+					{Quality: livekit.VideoQuality_HIGH, Enabled: false},
+				},
+			},
+			{
+				Codec: mime.MimeTypeAV1.String(),
+				Qualities: []*livekit.SubscribedQuality{
+					{Quality: livekit.VideoQuality_LOW, Enabled: true},
+					{Quality: livekit.VideoQuality_MEDIUM, Enabled: true},
+					{Quality: livekit.VideoQuality_HIGH, Enabled: true},
+				},
+			},
+		}
+		require.Eventually(t, func() bool {
+			lock.Lock()
+			defer lock.Unlock()
+
+			return subscribedCodecsAsString(expectedSubscribedQualities) == subscribedCodecsAsString(actualSubscribedQualities)
+		}, 10*time.Second, 100*time.Millisecond)
+	})
+
+	t.Run("subscribers max quality", func(t *testing.T) {
+		lock := sync.RWMutex{}
+		actualSubscribedQualities := make([]*livekit.SubscribedCodec, 0)
+
+		dm := NewDynacastManagerVideo(DynacastManagerVideoParams{
+			Listener: &testDynacastManagerListener{
+				onSubscribedMaxQualityChange: func(subscribedQualities []*livekit.SubscribedCodec) {
+					lock.Lock()
+					actualSubscribedQualities = subscribedQualities
+					lock.Unlock()
+				},
+			},
+		})
+
+		dm.(*dynacastManagerVideo).maxSubscribedQuality = map[mime.MimeType]livekit.VideoQuality{
+			mime.MimeTypeVP8: livekit.VideoQuality_LOW,
+			mime.MimeTypeAV1: livekit.VideoQuality_LOW,
+		}
+		dm.NotifySubscriberMaxQuality("s1", mime.MimeTypeVP8, livekit.VideoQuality_HIGH)
+		dm.NotifySubscriberMaxQuality("s2", mime.MimeTypeVP8, livekit.VideoQuality_MEDIUM)
+		dm.NotifySubscriberMaxQuality("s3", mime.MimeTypeAV1, livekit.VideoQuality_MEDIUM)
+
+		expectedSubscribedQualities := []*livekit.SubscribedCodec{
+			{
+				Codec: mime.MimeTypeVP8.String(),
+				Qualities: []*livekit.SubscribedQuality{
+					{Quality: livekit.VideoQuality_LOW, Enabled: true},
+					{Quality: livekit.VideoQuality_MEDIUM, Enabled: true},
+					{Quality: livekit.VideoQuality_HIGH, Enabled: true},
+				},
+			},
+			{
+				Codec: mime.MimeTypeAV1.String(),
+				Qualities: []*livekit.SubscribedQuality{
+					{Quality: livekit.VideoQuality_LOW, Enabled: true},
+					{Quality: livekit.VideoQuality_MEDIUM, Enabled: true},
+					{Quality: livekit.VideoQuality_HIGH, Enabled: false},
+				},
+			},
+		}
+		require.Eventually(t, func() bool {
+			lock.Lock()
+			defer lock.Unlock()
+
+			return subscribedCodecsAsString(expectedSubscribedQualities) == subscribedCodecsAsString(actualSubscribedQualities)
+		}, 10*time.Second, 100*time.Millisecond)
+
+		// "s1" dropping to MEDIUM should disable HIGH layer
+		dm.NotifySubscriberMaxQuality("s1", mime.MimeTypeVP8, livekit.VideoQuality_MEDIUM)
+
+		expectedSubscribedQualities = []*livekit.SubscribedCodec{
+			{
+				Codec: mime.MimeTypeVP8.String(),
+				Qualities: []*livekit.SubscribedQuality{
+					{Quality: livekit.VideoQuality_LOW, Enabled: true},
+					{Quality: livekit.VideoQuality_MEDIUM, Enabled: true},
+					{Quality: livekit.VideoQuality_HIGH, Enabled: false},
+				},
+			},
+			{
+				Codec: mime.MimeTypeAV1.String(),
+				Qualities: []*livekit.SubscribedQuality{
+					{Quality: livekit.VideoQuality_LOW, Enabled: true},
+					{Quality: livekit.VideoQuality_MEDIUM, Enabled: true},
+					{Quality: livekit.VideoQuality_HIGH, Enabled: false},
+				},
+			},
+		}
+		require.Eventually(t, func() bool {
+			lock.Lock()
+			defer lock.Unlock()
+
+			return subscribedCodecsAsString(expectedSubscribedQualities) == subscribedCodecsAsString(actualSubscribedQualities)
+		}, 10*time.Second, 100*time.Millisecond)
+
+		// "s1" , "s2" , "s3" dropping to LOW should disable HIGH & MEDIUM
+		dm.NotifySubscriberMaxQuality("s1", mime.MimeTypeVP8, livekit.VideoQuality_LOW)
+		dm.NotifySubscriberMaxQuality("s2", mime.MimeTypeVP8, livekit.VideoQuality_LOW)
+		dm.NotifySubscriberMaxQuality("s3", mime.MimeTypeAV1, livekit.VideoQuality_LOW)
+
+		expectedSubscribedQualities = []*livekit.SubscribedCodec{
+			{
+				Codec: mime.MimeTypeVP8.String(),
+				Qualities: []*livekit.SubscribedQuality{
+					{Quality: livekit.VideoQuality_LOW, Enabled: true},
+					{Quality: livekit.VideoQuality_MEDIUM, Enabled: false},
+					{Quality: livekit.VideoQuality_HIGH, Enabled: false},
+				},
+			},
+			{
+				Codec: mime.MimeTypeAV1.String(),
+				Qualities: []*livekit.SubscribedQuality{
+					{Quality: livekit.VideoQuality_LOW, Enabled: true},
+					{Quality: livekit.VideoQuality_MEDIUM, Enabled: false},
+					{Quality: livekit.VideoQuality_HIGH, Enabled: false},
+				},
+			},
+		}
+		require.Eventually(t, func() bool {
+			lock.Lock()
+			defer lock.Unlock()
+
+			return subscribedCodecsAsString(expectedSubscribedQualities) == subscribedCodecsAsString(actualSubscribedQualities)
+		}, 10*time.Second, 100*time.Millisecond)
+
+		// muting "s2" only should not disable all qualities of vp8, no change of expected qualities
+		dm.NotifySubscriberMaxQuality("s2", mime.MimeTypeVP8, livekit.VideoQuality_OFF)
+
+		time.Sleep(100 * time.Millisecond)
+		require.Eventually(t, func() bool {
+			lock.Lock()
+			defer lock.Unlock()
+
+			return subscribedCodecsAsString(expectedSubscribedQualities) == subscribedCodecsAsString(actualSubscribedQualities)
+		}, 10*time.Second, 100*time.Millisecond)
+
+		// muting "s1" and s3 also should disable all qualities
+		dm.NotifySubscriberMaxQuality("s1", mime.MimeTypeVP8, livekit.VideoQuality_OFF)
+		dm.NotifySubscriberMaxQuality("s3", mime.MimeTypeAV1, livekit.VideoQuality_OFF)
+
+		expectedSubscribedQualities = []*livekit.SubscribedCodec{
+			{
+				Codec: mime.MimeTypeVP8.String(),
+				Qualities: []*livekit.SubscribedQuality{
+					{Quality: livekit.VideoQuality_LOW, Enabled: false},
+					{Quality: livekit.VideoQuality_MEDIUM, Enabled: false},
+					{Quality: livekit.VideoQuality_HIGH, Enabled: false},
+				},
+			},
+			{
+				Codec: mime.MimeTypeAV1.String(),
+				Qualities: []*livekit.SubscribedQuality{
+					{Quality: livekit.VideoQuality_LOW, Enabled: false},
+					{Quality: livekit.VideoQuality_MEDIUM, Enabled: false},
+					{Quality: livekit.VideoQuality_HIGH, Enabled: false},
+				},
+			},
+		}
+		require.Eventually(t, func() bool {
+			lock.Lock()
+			defer lock.Unlock()
+
+			return subscribedCodecsAsString(expectedSubscribedQualities) == subscribedCodecsAsString(actualSubscribedQualities)
+		}, 10*time.Second, 100*time.Millisecond)
+
+		// unmuting "s1" should enable vp8 previously set max quality
+		dm.NotifySubscriberMaxQuality("s1", mime.MimeTypeVP8, livekit.VideoQuality_LOW)
+
+		expectedSubscribedQualities = []*livekit.SubscribedCodec{
+			{
+				Codec: mime.MimeTypeVP8.String(),
+				Qualities: []*livekit.SubscribedQuality{
+					{Quality: livekit.VideoQuality_LOW, Enabled: true},
+					{Quality: livekit.VideoQuality_MEDIUM, Enabled: false},
+					{Quality: livekit.VideoQuality_HIGH, Enabled: false},
+				},
+			},
+			{
+				Codec: mime.MimeTypeAV1.String(),
+				Qualities: []*livekit.SubscribedQuality{
+					{Quality: livekit.VideoQuality_LOW, Enabled: false},
+					{Quality: livekit.VideoQuality_MEDIUM, Enabled: false},
+					{Quality: livekit.VideoQuality_HIGH, Enabled: false},
+				},
+			},
+		}
+		require.Eventually(t, func() bool {
+			lock.Lock()
+			defer lock.Unlock()
+
+			return subscribedCodecsAsString(expectedSubscribedQualities) == subscribedCodecsAsString(actualSubscribedQualities)
+		}, 10*time.Second, 100*time.Millisecond)
+
+		// a higher quality from a different node should trigger that quality
+		dm.NotifySubscriberNodeMaxQuality("n1", []types.SubscribedCodecQuality{
+			{CodecMime: mime.MimeTypeVP8, Quality: livekit.VideoQuality_HIGH},
+			{CodecMime: mime.MimeTypeAV1, Quality: livekit.VideoQuality_MEDIUM},
+		})
+
+		expectedSubscribedQualities = []*livekit.SubscribedCodec{
+			{
+				Codec: mime.MimeTypeVP8.String(),
+				Qualities: []*livekit.SubscribedQuality{
+					{Quality: livekit.VideoQuality_LOW, Enabled: true},
+					{Quality: livekit.VideoQuality_MEDIUM, Enabled: true},
+					{Quality: livekit.VideoQuality_HIGH, Enabled: true},
+				},
+			},
+			{
+				Codec: mime.MimeTypeAV1.String(),
+				Qualities: []*livekit.SubscribedQuality{
+					{Quality: livekit.VideoQuality_LOW, Enabled: true},
+					{Quality: livekit.VideoQuality_MEDIUM, Enabled: true},
+					{Quality: livekit.VideoQuality_HIGH, Enabled: false},
+				},
+			},
+		}
+		require.Eventually(t, func() bool {
+			lock.Lock()
+			defer lock.Unlock()
+
+			return subscribedCodecsAsString(expectedSubscribedQualities) == subscribedCodecsAsString(actualSubscribedQualities)
+		}, 10*time.Second, 100*time.Millisecond)
+	})
+}
+
+func TestCodecRegression(t *testing.T) {
+	t.Run("codec regression video", func(t *testing.T) {
+		var lock sync.Mutex
+		actualSubscribedQualities := make([]*livekit.SubscribedCodec, 0)
+
+		dm := NewDynacastManagerVideo(DynacastManagerVideoParams{
+			Listener: &testDynacastManagerListener{
+				onSubscribedMaxQualityChange: func(subscribedQualities []*livekit.SubscribedCodec) {
+					lock.Lock()
+					actualSubscribedQualities = subscribedQualities
+					lock.Unlock()
+				},
+			},
+		})
+
+		dm.NotifySubscriberMaxQuality("s1", mime.MimeTypeAV1, livekit.VideoQuality_HIGH)
+
+		expectedSubscribedQualities := []*livekit.SubscribedCodec{
+			{
+				Codec: mime.MimeTypeAV1.String(),
+				Qualities: []*livekit.SubscribedQuality{
+					{Quality: livekit.VideoQuality_LOW, Enabled: true},
+					{Quality: livekit.VideoQuality_MEDIUM, Enabled: true},
+					{Quality: livekit.VideoQuality_HIGH, Enabled: true},
+				},
+			},
+		}
+		require.Eventually(t, func() bool {
+			lock.Lock()
+			defer lock.Unlock()
+
+			return subscribedCodecsAsString(expectedSubscribedQualities) == subscribedCodecsAsString(actualSubscribedQualities)
+		}, 10*time.Second, 100*time.Millisecond)
+
+		dm.HandleCodecRegression(mime.MimeTypeAV1, mime.MimeTypeVP8)
+
+		expectedSubscribedQualities = []*livekit.SubscribedCodec{
+			{
+				Codec: mime.MimeTypeAV1.String(),
+				Qualities: []*livekit.SubscribedQuality{
+					{Quality: livekit.VideoQuality_LOW, Enabled: false},
+					{Quality: livekit.VideoQuality_MEDIUM, Enabled: false},
+					{Quality: livekit.VideoQuality_HIGH, Enabled: false},
+				},
+			},
+			{
+				Codec: mime.MimeTypeVP8.String(),
+				Qualities: []*livekit.SubscribedQuality{
+					{Quality: livekit.VideoQuality_LOW, Enabled: true},
+					{Quality: livekit.VideoQuality_MEDIUM, Enabled: true},
+					{Quality: livekit.VideoQuality_HIGH, Enabled: true},
+				},
+			},
+		}
+		require.Eventually(t, func() bool {
+			lock.Lock()
+			defer lock.Unlock()
+
+			return subscribedCodecsAsString(expectedSubscribedQualities) == subscribedCodecsAsString(actualSubscribedQualities)
+		}, 10*time.Second, 100*time.Millisecond)
+
+		// av1 quality change should be forwarded to vp8
+		// av1 quality change of node should be ignored
+		dm.NotifySubscriberMaxQuality("s1", mime.MimeTypeAV1, livekit.VideoQuality_MEDIUM)
+		dm.NotifySubscriberNodeMaxQuality("n1", []types.SubscribedCodecQuality{
+			{CodecMime: mime.MimeTypeAV1, Quality: livekit.VideoQuality_HIGH},
+		})
+		expectedSubscribedQualities = []*livekit.SubscribedCodec{
+			{
+				Codec: mime.MimeTypeAV1.String(),
+				Qualities: []*livekit.SubscribedQuality{
+					{Quality: livekit.VideoQuality_LOW, Enabled: false},
+					{Quality: livekit.VideoQuality_MEDIUM, Enabled: false},
+					{Quality: livekit.VideoQuality_HIGH, Enabled: false},
+				},
+			},
+			{
+				Codec: mime.MimeTypeVP8.String(),
+				Qualities: []*livekit.SubscribedQuality{
+					{Quality: livekit.VideoQuality_LOW, Enabled: true},
+					{Quality: livekit.VideoQuality_MEDIUM, Enabled: true},
+					{Quality: livekit.VideoQuality_HIGH, Enabled: false},
+				},
+			},
+		}
+		require.Eventually(t, func() bool {
+			lock.Lock()
+			defer lock.Unlock()
+
+			return subscribedCodecsAsString(expectedSubscribedQualities) == subscribedCodecsAsString(actualSubscribedQualities)
+		}, 10*time.Second, 100*time.Millisecond)
+	})
+
+	t.Run("codec regression audio", func(t *testing.T) {
+		var lock sync.Mutex
+		actualSubscribedCodecs := make([]*livekit.SubscribedAudioCodec, 0)
+
+		dm := NewDynacastManagerAudio(DynacastManagerAudioParams{
+			Listener: &testDynacastManagerListener{
+				onSubscribedAudioCodecChange: func(subscribedCodecs []*livekit.SubscribedAudioCodec) {
+					lock.Lock()
+					actualSubscribedCodecs = subscribedCodecs
+					lock.Unlock()
+				},
+			},
+		})
+
+		dm.NotifySubscription("s1", mime.MimeTypeRED, true)
+
+		expectedSubscribedCodecs := []*livekit.SubscribedAudioCodec{
+			{
+				Codec:   mime.MimeTypeRED.String(),
+				Enabled: true,
+			},
+		}
+		require.Eventually(t, func() bool {
+			lock.Lock()
+			defer lock.Unlock()
+
+			return subscribedAudioCodecsAsString(expectedSubscribedCodecs) == subscribedAudioCodecsAsString(actualSubscribedCodecs)
+		}, 10*time.Second, 100*time.Millisecond)
+
+		dm.HandleCodecRegression(mime.MimeTypeRED, mime.MimeTypeOpus)
+
+		expectedSubscribedCodecs = []*livekit.SubscribedAudioCodec{
+			{
+				Codec:   mime.MimeTypeRED.String(),
+				Enabled: false,
+			},
+			{
+				Codec:   mime.MimeTypeOpus.String(),
+				Enabled: true,
+			},
+		}
+		require.Eventually(t, func() bool {
+			lock.Lock()
+			defer lock.Unlock()
+
+			return subscribedAudioCodecsAsString(expectedSubscribedCodecs) == subscribedAudioCodecsAsString(actualSubscribedCodecs)
+		}, 10*time.Second, 100*time.Millisecond)
+
+		// RED disable as subscriber or subscriber node should be ignored as it has been regressed
+		dm.NotifySubscription("s1", mime.MimeTypeRED, false)
+		dm.NotifySubscriptionNode("n1", []*livekit.SubscribedAudioCodec{
+			{Codec: mime.MimeTypeRED.String(), Enabled: false},
+		})
+		require.Eventually(t, func() bool {
+			lock.Lock()
+			defer lock.Unlock()
+
+			return subscribedAudioCodecsAsString(expectedSubscribedCodecs) == subscribedAudioCodecsAsString(actualSubscribedCodecs)
+		}, 10*time.Second, 100*time.Millisecond)
+
+		// `s1` unsubscription should turn off `opus`
+		dm.NotifySubscription("s1", mime.MimeTypeOpus, false)
+		expectedSubscribedCodecs = []*livekit.SubscribedAudioCodec{
+			{
+				Codec:   mime.MimeTypeRED.String(),
+				Enabled: false,
+			},
+			{
+				Codec:   mime.MimeTypeOpus.String(),
+				Enabled: false,
+			},
+		}
+		require.Eventually(t, func() bool {
+			lock.Lock()
+			defer lock.Unlock()
+
+			return subscribedAudioCodecsAsString(expectedSubscribedCodecs) == subscribedAudioCodecsAsString(actualSubscribedCodecs)
+		}, 10*time.Second, 100*time.Millisecond)
+
+		// a node subscription should turn `opus` back on
+		dm.NotifySubscriptionNode("n1", []*livekit.SubscribedAudioCodec{
+			{
+				Codec:   mime.MimeTypeOpus.String(),
+				Enabled: true,
+			},
+		})
+		expectedSubscribedCodecs = []*livekit.SubscribedAudioCodec{
+			{
+				Codec:   mime.MimeTypeRED.String(),
+				Enabled: false,
+			},
+			{
+				Codec:   mime.MimeTypeOpus.String(),
+				Enabled: true,
+			},
+		}
+		require.Eventually(t, func() bool {
+			lock.Lock()
+			defer lock.Unlock()
+
+			return subscribedAudioCodecsAsString(expectedSubscribedCodecs) == subscribedAudioCodecsAsString(actualSubscribedCodecs)
+		}, 10*time.Second, 100*time.Millisecond)
+
+	})
+}
+
+func subscribedCodecsAsString(c1 []*livekit.SubscribedCodec) string {
+	slices.SortFunc(c1, func(a, b *livekit.SubscribedCodec) int {
+		return strings.Compare(a.Codec, b.Codec)
+	})
+
+	var s1 strings.Builder
+	for _, c := range c1 {
+		s1.WriteString(c.String())
+	}
+	return s1.String()
+}
+
+func subscribedAudioCodecsAsString(c1 []*livekit.SubscribedAudioCodec) string {
+	slices.SortFunc(c1, func(a, b *livekit.SubscribedAudioCodec) int {
+		return strings.Compare(a.Codec, b.Codec)
+	})
+
+	var s1 strings.Builder
+	for _, c := range c1 {
+		s1.WriteString(c.String())
+	}
+	return s1.String()
+}

pkg/rtc/dynacast/dynacastmanageraudio.go

@@ -0,0 +1,198 @@
+// 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 (
+	"github.com/livekit/protocol/livekit"
+	"github.com/livekit/protocol/logger"
+
+	"github.com/livekit/protocol/codecs/mime"
+)
+
+var _ DynacastManager = (*dynacastManagerAudio)(nil)
+var _ dynacastQualityListener = (*dynacastManagerAudio)(nil)
+
+type DynacastManagerAudioParams struct {
+	Listener DynacastManagerListener
+	Logger   logger.Logger
+}
+
+type dynacastManagerAudio struct {
+	params DynacastManagerAudioParams
+
+	subscribedCodecs          map[mime.MimeType]bool
+	committedSubscribedCodecs map[mime.MimeType]bool
+
+	isClosed bool
+
+	*dynacastManagerBase
+}
+
+func NewDynacastManagerAudio(params DynacastManagerAudioParams) DynacastManager {
+	if params.Logger == nil {
+		params.Logger = logger.GetLogger()
+	}
+	d := &dynacastManagerAudio{
+		params:                    params,
+		subscribedCodecs:          make(map[mime.MimeType]bool),
+		committedSubscribedCodecs: make(map[mime.MimeType]bool),
+	}
+	d.dynacastManagerBase = newDynacastManagerBase(dynacastManagerBaseParams{
+		Logger:        params.Logger,
+		OpsQueueDepth: 4,
+		OnRestart: func() {
+			d.committedSubscribedCodecs = make(map[mime.MimeType]bool)
+		},
+		OnDynacastQualityCreate: func(mimeType mime.MimeType) dynacastQuality {
+			dq := newDynacastQualityAudio(dynacastQualityAudioParams{
+				MimeType: mimeType,
+				Listener: d,
+				Logger:   d.params.Logger,
+			})
+			return dq
+		},
+		OnRegressCodec: func(fromMime, toMime mime.MimeType) {
+			d.subscribedCodecs[fromMime] = false
+
+			// if the new codec is not added, notify the publisher to start publishing
+			if _, ok := d.subscribedCodecs[toMime]; !ok {
+				d.subscribedCodecs[toMime] = true
+			}
+		},
+		OnUpdateNeeded: d.update,
+	})
+	return d
+}
+
+// It is possible for tracks to be in pending close state. When track
+// is waiting to be closed, a node is not streaming a track. This can
+// be used to force an update announcing that subscribed codec is disabled,
+// i.e. indicating not pulling track any more.
+func (d *dynacastManagerAudio) ForceEnable(enabled bool) {
+	d.lock.Lock()
+	defer d.lock.Unlock()
+
+	for mime := range d.committedSubscribedCodecs {
+		d.committedSubscribedCodecs[mime] = enabled
+	}
+
+	d.enqueueSubscribedChange()
+}
+
+func (d *dynacastManagerAudio) NotifySubscription(
+	subscriberID livekit.ParticipantID,
+	mime mime.MimeType,
+	enabled bool,
+) {
+	dq := d.getOrCreateDynacastQuality(mime)
+	if dq != nil {
+		dq.NotifySubscription(subscriberID, enabled)
+	}
+}
+
+func (d *dynacastManagerAudio) NotifySubscriptionNode(
+	nodeID livekit.NodeID,
+	codecs []*livekit.SubscribedAudioCodec,
+) {
+	for _, codec := range codecs {
+		dq := d.getOrCreateDynacastQuality(mime.NormalizeMimeType(codec.Codec))
+		if dq != nil {
+			dq.NotifySubscriptionNode(nodeID, codec.Enabled)
+		}
+	}
+}
+
+func (d *dynacastManagerAudio) OnUpdateAudioCodecForMime(mime mime.MimeType, enabled bool) {
+	d.lock.Lock()
+	if _, ok := d.regressedCodec[mime]; !ok {
+		d.subscribedCodecs[mime] = enabled
+	}
+	d.lock.Unlock()
+
+	d.update(false)
+}
+
+func (d *dynacastManagerAudio) update(force bool) {
+	d.lock.Lock()
+
+	d.params.Logger.Debugw(
+		"processing subscribed codec change",
+		"force", force,
+		"committedSubscribedCodecs", d.committedSubscribedCodecs,
+		"subscribedCodecs", d.subscribedCodecs,
+	)
+
+	if len(d.subscribedCodecs) == 0 {
+		// no mime has been added, nothing to update
+		d.lock.Unlock()
+		return
+	}
+
+	// add or remove of a mime triggers an update
+	changed := len(d.subscribedCodecs) != len(d.committedSubscribedCodecs)
+	if !changed {
+		for mime, enabled := range d.subscribedCodecs {
+			if ce, ok := d.committedSubscribedCodecs[mime]; ok {
+				if ce != enabled {
+					changed = true
+					break
+				}
+			}
+		}
+	}
+
+	if !force && !changed {
+		d.lock.Unlock()
+		return
+	}
+
+	d.params.Logger.Debugw(
+		"committing subscribed codec change",
+		"force", force,
+		"committedSubscribedCoecs", d.committedSubscribedCodecs,
+		"subscribedcodecs", d.subscribedCodecs,
+	)
+
+	// commit change
+	d.committedSubscribedCodecs = make(map[mime.MimeType]bool, len(d.subscribedCodecs))
+	for mime, enabled := range d.subscribedCodecs {
+		d.committedSubscribedCodecs[mime] = enabled
+	}
+
+	d.enqueueSubscribedChange()
+	d.lock.Unlock()
+}
+
+func (d *dynacastManagerAudio) enqueueSubscribedChange() {
+	if d.isClosed || d.params.Listener == nil {
+		return
+	}
+
+	subscribedCodecs := make([]*livekit.SubscribedAudioCodec, 0, len(d.committedSubscribedCodecs))
+	for mime, enabled := range d.committedSubscribedCodecs {
+		subscribedCodecs = append(subscribedCodecs, &livekit.SubscribedAudioCodec{
+			Codec:   mime.String(),
+			Enabled: enabled,
+		})
+	}
+
+	d.params.Logger.Debugw(
+		"subscribedAudioCodecChange",
+		"subscribedCodecs", logger.ProtoSlice(subscribedCodecs),
+	)
+	d.notifyOpsQueue.Enqueue(func() {
+		d.params.Listener.OnDynacastSubscribedAudioCodecChange(subscribedCodecs)
+	})
+}

pkg/rtc/dynacast/dynacastmanagerbase.go

@@ -0,0 +1,165 @@
+// 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 (
+	"maps"
+	"slices"
+	"sync"
+
+	"github.com/livekit/protocol/codecs/mime"
+	"github.com/livekit/protocol/logger"
+
+	"github.com/livekit/livekit-server/pkg/utils"
+)
+
+type dynacastManagerBaseParams struct {
+	Logger                  logger.Logger
+	OpsQueueDepth           uint
+	OnRestart               func()
+	OnDynacastQualityCreate func(mimeType mime.MimeType) dynacastQuality
+	OnRegressCodec          func(fromMime, toMime mime.MimeType)
+	OnUpdateNeeded          func(force bool)
+}
+
+type dynacastManagerBase struct {
+	params dynacastManagerBaseParams
+
+	lock            sync.RWMutex
+	regressedCodec  map[mime.MimeType]struct{}
+	dynacastQuality map[mime.MimeType]dynacastQuality
+
+	notifyOpsQueue *utils.OpsQueue
+
+	isClosed bool
+
+	dynacastManagerNull
+	dynacastQualityListenerNull
+}
+
+func newDynacastManagerBase(params dynacastManagerBaseParams) *dynacastManagerBase {
+	if params.OpsQueueDepth == 0 {
+		params.OpsQueueDepth = 4
+	}
+	d := &dynacastManagerBase{
+		params:          params,
+		regressedCodec:  make(map[mime.MimeType]struct{}),
+		dynacastQuality: make(map[mime.MimeType]dynacastQuality),
+		notifyOpsQueue: utils.NewOpsQueue(utils.OpsQueueParams{
+			Name:        "dynacast-notify",
+			MinSize:     params.OpsQueueDepth,
+			FlushOnStop: true,
+			Logger:      params.Logger,
+		}),
+	}
+	d.notifyOpsQueue.Start()
+	return d
+}
+
+func (d *dynacastManagerBase) AddCodec(mime mime.MimeType) {
+	d.getOrCreateDynacastQuality(mime)
+}
+
+func (d *dynacastManagerBase) HandleCodecRegression(fromMime, toMime mime.MimeType) {
+	fromDq := d.getOrCreateDynacastQuality(fromMime)
+
+	d.lock.Lock()
+	if d.isClosed {
+		d.lock.Unlock()
+		return
+	}
+
+	if fromDq == nil {
+		// should not happen as we have added the codec on setup receiver
+		d.params.Logger.Warnw("regression from codec not found", nil, "mime", fromMime, "toMime", toMime)
+		d.lock.Unlock()
+		return
+	}
+	d.regressedCodec[fromMime] = struct{}{}
+	d.params.OnRegressCodec(fromMime, toMime)
+	d.lock.Unlock()
+
+	d.params.OnUpdateNeeded(false)
+
+	fromDq.Stop()
+	fromDq.RegressTo(d.getOrCreateDynacastQuality(toMime))
+}
+
+func (d *dynacastManagerBase) Restart() {
+	d.lock.Lock()
+	d.params.OnRestart()
+
+	dqs := d.getDynacastQualitiesLocked()
+	d.lock.Unlock()
+
+	for _, dq := range dqs {
+		dq.Restart()
+	}
+}
+
+func (d *dynacastManagerBase) Close() {
+	d.notifyOpsQueue.Stop()
+
+	d.lock.Lock()
+	dqs := d.getDynacastQualitiesLocked()
+	d.dynacastQuality = make(map[mime.MimeType]dynacastQuality)
+
+	d.isClosed = true
+	d.lock.Unlock()
+
+	for _, dq := range dqs {
+		dq.Stop()
+	}
+}
+
+// There are situations like track unmute or streaming from a different node
+// where subscription changes needs to sent to the provider immediately.
+// This bypasses any debouncing and forces a subscription change update
+// with immediate effect.
+func (d *dynacastManagerBase) ForceUpdate() {
+	d.params.OnUpdateNeeded(true)
+}
+
+func (d *dynacastManagerBase) ClearSubscriberNodes() {
+	d.lock.Lock()
+	dqs := d.getDynacastQualitiesLocked()
+	d.lock.Unlock()
+	for _, dq := range dqs {
+		dq.ClearSubscriberNodes()
+	}
+}
+
+func (d *dynacastManagerBase) getOrCreateDynacastQuality(mimeType mime.MimeType) dynacastQuality {
+	d.lock.Lock()
+	defer d.lock.Unlock()
+
+	if d.isClosed || mimeType == mime.MimeTypeUnknown {
+		return nil
+	}
+
+	if dq := d.dynacastQuality[mimeType]; dq != nil {
+		return dq
+	}
+
+	dq := d.params.OnDynacastQualityCreate(mimeType)
+	dq.Start()
+
+	d.dynacastQuality[mimeType] = dq
+	return dq
+}
+
+func (d *dynacastManagerBase) getDynacastQualitiesLocked() []dynacastQuality {
+	return slices.Collect(maps.Values(d.dynacastQuality))
+}

pkg/rtc/dynacast/dynacastmanagervideo.go

@@ -0,0 +1,271 @@
+// 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 (
+	"maps"
+	"time"
+
+	"github.com/bep/debounce"
+
+	"github.com/livekit/protocol/codecs/mime"
+	"github.com/livekit/protocol/livekit"
+	"github.com/livekit/protocol/logger"
+
+	"github.com/livekit/livekit-server/pkg/rtc/types"
+)
+
+var _ DynacastManager = (*dynacastManagerVideo)(nil)
+var _ dynacastQualityListener = (*dynacastManagerVideo)(nil)
+
+type DynacastManagerVideoParams struct {
+	DynacastPauseDelay time.Duration
+	Listener           DynacastManagerListener
+	Logger             logger.Logger
+}
+
+type dynacastManagerVideo struct {
+	params DynacastManagerVideoParams
+
+	maxSubscribedQuality          map[mime.MimeType]livekit.VideoQuality
+	committedMaxSubscribedQuality map[mime.MimeType]livekit.VideoQuality
+
+	maxSubscribedQualityDebounce        func(func())
+	maxSubscribedQualityDebouncePending bool
+
+	isClosed bool
+
+	*dynacastManagerBase
+}
+
+func NewDynacastManagerVideo(params DynacastManagerVideoParams) DynacastManager {
+	if params.Logger == nil {
+		params.Logger = logger.GetLogger()
+	}
+	d := &dynacastManagerVideo{
+		params:                        params,
+		maxSubscribedQuality:          make(map[mime.MimeType]livekit.VideoQuality),
+		committedMaxSubscribedQuality: make(map[mime.MimeType]livekit.VideoQuality),
+	}
+	if params.DynacastPauseDelay > 0 {
+		d.maxSubscribedQualityDebounce = debounce.New(params.DynacastPauseDelay)
+	}
+	d.dynacastManagerBase = newDynacastManagerBase(dynacastManagerBaseParams{
+		Logger:        params.Logger,
+		OpsQueueDepth: 64,
+		OnRestart: func() {
+			d.committedMaxSubscribedQuality = make(map[mime.MimeType]livekit.VideoQuality)
+		},
+		OnDynacastQualityCreate: func(mimeType mime.MimeType) dynacastQuality {
+			dq := newDynacastQualityVideo(dynacastQualityVideoParams{
+				MimeType: mimeType,
+				Listener: d,
+				Logger:   d.params.Logger,
+			})
+			return dq
+		},
+		OnRegressCodec: func(fromMime, toMime mime.MimeType) {
+			d.maxSubscribedQuality[fromMime] = livekit.VideoQuality_OFF
+
+			// if the new codec is not added, notify the publisher to start publishing
+			if _, ok := d.maxSubscribedQuality[toMime]; !ok {
+				d.maxSubscribedQuality[toMime] = livekit.VideoQuality_HIGH
+			}
+		},
+		OnUpdateNeeded: d.update,
+	})
+	return d
+}
+
+// It is possible for tracks to be in pending close state. When track
+// is waiting to be closed, a node is not streaming a track. This can
+// be used to force an update announcing that subscribed quality is OFF,
+// i.e. indicating not pulling track any more.
+func (d *dynacastManagerVideo) ForceQuality(quality livekit.VideoQuality) {
+	d.lock.Lock()
+	defer d.lock.Unlock()
+
+	for mime := range d.committedMaxSubscribedQuality {
+		d.committedMaxSubscribedQuality[mime] = quality
+	}
+
+	d.enqueueSubscribedQualityChange()
+}
+
+func (d *dynacastManagerVideo) NotifySubscriberMaxQuality(
+	subscriberID livekit.ParticipantID,
+	mime mime.MimeType,
+	quality livekit.VideoQuality,
+) {
+	dq := d.getOrCreateDynacastQuality(mime)
+	if dq != nil {
+		dq.NotifySubscriberMaxQuality(subscriberID, quality)
+	}
+}
+
+func (d *dynacastManagerVideo) NotifySubscriberNodeMaxQuality(
+	nodeID livekit.NodeID,
+	qualities []types.SubscribedCodecQuality,
+) {
+	for _, quality := range qualities {
+		dq := d.getOrCreateDynacastQuality(quality.CodecMime)
+		if dq != nil {
+			dq.NotifySubscriberNodeMaxQuality(nodeID, quality.Quality)
+		}
+	}
+}
+
+func (d *dynacastManagerVideo) OnUpdateMaxQualityForMime(
+	mime mime.MimeType,
+	maxQuality livekit.VideoQuality,
+) {
+	d.lock.Lock()
+	if _, ok := d.regressedCodec[mime]; !ok {
+		d.maxSubscribedQuality[mime] = maxQuality
+	}
+	d.lock.Unlock()
+
+	d.update(false)
+}
+
+func (d *dynacastManagerVideo) update(force bool) {
+	d.lock.Lock()
+
+	d.params.Logger.Debugw(
+		"processing quality change",
+		"force", force,
+		"committedMaxSubscribedQuality", d.committedMaxSubscribedQuality,
+		"maxSubscribedQuality", d.maxSubscribedQuality,
+	)
+
+	if len(d.maxSubscribedQuality) == 0 {
+		// no mime has been added, nothing to update
+		d.lock.Unlock()
+		return
+	}
+
+	// add or remove of a mime triggers an update
+	changed := len(d.maxSubscribedQuality) != len(d.committedMaxSubscribedQuality)
+	downgradesOnly := !changed
+	if !changed {
+		for mime, quality := range d.maxSubscribedQuality {
+			if cq, ok := d.committedMaxSubscribedQuality[mime]; ok {
+				if cq != quality {
+					changed = true
+				}
+
+				if (cq == livekit.VideoQuality_OFF && quality != livekit.VideoQuality_OFF) || (cq != livekit.VideoQuality_OFF && quality != livekit.VideoQuality_OFF && cq < quality) {
+					downgradesOnly = false
+				}
+			}
+		}
+	}
+
+	if !force {
+		if !changed {
+			d.lock.Unlock()
+			return
+		}
+
+		if downgradesOnly && d.maxSubscribedQualityDebounce != nil {
+			if !d.maxSubscribedQualityDebouncePending {
+				d.params.Logger.Debugw(
+					"debouncing quality downgrade",
+					"committedMaxSubscribedQuality", d.committedMaxSubscribedQuality,
+					"maxSubscribedQuality", d.maxSubscribedQuality,
+				)
+				d.maxSubscribedQualityDebounce(func() {
+					d.update(true)
+				})
+				d.maxSubscribedQualityDebouncePending = true
+			} else {
+				d.params.Logger.Debugw(
+					"quality downgrade waiting for debounce",
+					"committedMaxSubscribedQuality", d.committedMaxSubscribedQuality,
+					"maxSubscribedQuality", d.maxSubscribedQuality,
+				)
+			}
+			d.lock.Unlock()
+			return
+		}
+	}
+
+	// clear debounce on send
+	if d.maxSubscribedQualityDebounce != nil {
+		d.maxSubscribedQualityDebounce(func() {})
+		d.maxSubscribedQualityDebouncePending = false
+	}
+
+	d.params.Logger.Debugw(
+		"committing quality change",
+		"force", force,
+		"committedMaxSubscribedQuality", d.committedMaxSubscribedQuality,
+		"maxSubscribedQuality", d.maxSubscribedQuality,
+	)
+
+	// commit change
+	d.committedMaxSubscribedQuality = make(map[mime.MimeType]livekit.VideoQuality, len(d.maxSubscribedQuality))
+	maps.Copy(d.committedMaxSubscribedQuality, d.maxSubscribedQuality)
+
+	d.enqueueSubscribedQualityChange()
+	d.lock.Unlock()
+}
+
+func (d *dynacastManagerVideo) enqueueSubscribedQualityChange() {
+	if d.isClosed || d.params.Listener == nil {
+		return
+	}
+
+	subscribedCodecs := make([]*livekit.SubscribedCodec, 0, len(d.committedMaxSubscribedQuality))
+	maxSubscribedQualities := make([]types.SubscribedCodecQuality, 0, len(d.committedMaxSubscribedQuality))
+	for mime, quality := range d.committedMaxSubscribedQuality {
+		maxSubscribedQualities = append(maxSubscribedQualities, types.SubscribedCodecQuality{
+			CodecMime: mime,
+			Quality:   quality,
+		})
+
+		if quality == livekit.VideoQuality_OFF {
+			subscribedCodecs = append(subscribedCodecs, &livekit.SubscribedCodec{
+				Codec: mime.String(),
+				Qualities: []*livekit.SubscribedQuality{
+					{Quality: livekit.VideoQuality_LOW, Enabled: false},
+					{Quality: livekit.VideoQuality_MEDIUM, Enabled: false},
+					{Quality: livekit.VideoQuality_HIGH, Enabled: false},
+				},
+			})
+		} else {
+			var subscribedQualities []*livekit.SubscribedQuality
+			for q := livekit.VideoQuality_LOW; q <= livekit.VideoQuality_HIGH; q++ {
+				subscribedQualities = append(subscribedQualities, &livekit.SubscribedQuality{
+					Quality: q,
+					Enabled: q <= quality,
+				})
+			}
+			subscribedCodecs = append(subscribedCodecs, &livekit.SubscribedCodec{
+				Codec:     mime.String(),
+				Qualities: subscribedQualities,
+			})
+		}
+	}
+
+	d.params.Logger.Debugw(
+		"subscribedMaxQualityChange",
+		"subscribedCodecs", subscribedCodecs,
+		"maxSubscribedQualities", maxSubscribedQualities,
+	)
+	d.notifyOpsQueue.Enqueue(func() {
+		d.params.Listener.OnDynacastSubscribedMaxQualityChange(subscribedCodecs, maxSubscribedQualities)
+	})
+}

pkg/rtc/dynacast/dynacastqualityaudio.go

@@ -0,0 +1,168 @@
+// 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"
+
+	"github.com/livekit/protocol/codecs/mime"
+	"github.com/livekit/protocol/livekit"
+	"github.com/livekit/protocol/logger"
+)
+
+var _ dynacastQuality = (*dynacastQualityAudio)(nil)
+
+type dynacastQualityAudioParams struct {
+	MimeType mime.MimeType
+	Listener dynacastQualityListener
+	Logger   logger.Logger
+}
+
+// dynacastQualityAudio manages enable a single receiver of a media track
+type dynacastQualityAudio struct {
+	params dynacastQualityAudioParams
+
+	// quality level enable/disable
+	lock                  sync.RWMutex
+	initialized           bool
+	subscriberEnables     map[livekit.ParticipantID]bool
+	subscriberNodeEnables map[livekit.NodeID]bool
+	enabled               bool
+	regressTo             dynacastQuality
+
+	dynacastQualityNull
+}
+
+func newDynacastQualityAudio(params dynacastQualityAudioParams) dynacastQuality {
+	return &dynacastQualityAudio{
+		params:                params,
+		subscriberEnables:     make(map[livekit.ParticipantID]bool),
+		subscriberNodeEnables: make(map[livekit.NodeID]bool),
+	}
+}
+
+func (d *dynacastQualityAudio) Start() {
+	d.reset()
+}
+
+func (d *dynacastQualityAudio) Restart() {
+	d.reset()
+}
+
+func (d *dynacastQualityAudio) Stop() {
+}
+
+func (d *dynacastQualityAudio) NotifySubscription(subscriberID livekit.ParticipantID, enabled bool) {
+	d.params.Logger.Debugw(
+		"setting subscriber codec enable",
+		"mime", d.params.MimeType,
+		"subscriberID", subscriberID,
+		"enabled", enabled,
+	)
+
+	d.lock.Lock()
+	if r := d.regressTo; r != nil {
+		d.lock.Unlock()
+		return
+	}
+
+	if !enabled {
+		delete(d.subscriberEnables, subscriberID)
+	} else {
+		d.subscriberEnables[subscriberID] = true
+	}
+	d.lock.Unlock()
+
+	d.updateQualityChange(false)
+}
+
+func (d *dynacastQualityAudio) NotifySubscriptionNode(nodeID livekit.NodeID, enabled bool) {
+	d.params.Logger.Debugw(
+		"setting subscriber node codec enabled",
+		"mime", d.params.MimeType,
+		"subscriberNodeID", nodeID,
+		"enabled", enabled,
+	)
+
+	d.lock.Lock()
+	if r := d.regressTo; r != nil {
+		// the downstream node will synthesize correct enable (its dynacast manager has codec regression), just ignore it
+		d.params.Logger.Debugw(
+			"ignoring node codec change, regressed to another dynacast quality",
+			"mime", d.params.MimeType,
+			"regressedMime", d.regressTo.Mime(),
+		)
+		d.lock.Unlock()
+		return
+	}
+
+	if !enabled {
+		delete(d.subscriberNodeEnables, nodeID)
+	} else {
+		d.subscriberNodeEnables[nodeID] = true
+	}
+	d.lock.Unlock()
+
+	d.updateQualityChange(false)
+}
+
+func (d *dynacastQualityAudio) ClearSubscriberNodes() {
+	d.lock.Lock()
+	d.subscriberNodeEnables = make(map[livekit.NodeID]bool)
+	d.lock.Unlock()
+
+	d.updateQualityChange(false)
+}
+
+func (d *dynacastQualityAudio) Mime() mime.MimeType {
+	return d.params.MimeType
+}
+
+func (d *dynacastQualityAudio) RegressTo(other dynacastQuality) {
+	d.lock.Lock()
+	d.regressTo = other
+	d.lock.Unlock()
+
+	other.Restart()
+}
+
+func (d *dynacastQualityAudio) reset() {
+	d.lock.Lock()
+	d.initialized = false
+	d.lock.Unlock()
+}
+
+func (d *dynacastQualityAudio) updateQualityChange(force bool) {
+	d.lock.Lock()
+	enabled := len(d.subscriberEnables) != 0 || len(d.subscriberNodeEnables) != 0
+	if enabled == d.enabled && d.initialized && !force {
+		d.lock.Unlock()
+		return
+	}
+
+	d.initialized = true
+	d.enabled = enabled
+	d.params.Logger.Debugw(
+		"notifying enabled change",
+		"mime", d.params.MimeType,
+		"enabled", d.enabled,
+		"subscriberNodeEnables", d.subscriberNodeEnables,
+		"subscribedEnables", d.subscriberEnables,
+		"force", force,
+	)
+	d.lock.Unlock()
+
+	d.params.Listener.OnUpdateAudioCodecForMime(d.params.MimeType, enabled)
+}

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
+	}
+}

pkg/rtc/dynacast/interfaces.go

@@ -0,0 +1,185 @@
+// 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 (
+	"github.com/livekit/protocol/codecs/mime"
+	"github.com/livekit/protocol/livekit"
+
+	"github.com/livekit/livekit-server/pkg/rtc/types"
+)
+
+type DynacastManagerListener interface {
+	OnDynacastSubscribedMaxQualityChange(
+		subscribedQualities []*livekit.SubscribedCodec,
+		maxSubscribedQualities []types.SubscribedCodecQuality,
+	)
+
+	OnDynacastSubscribedAudioCodecChange(codecs []*livekit.SubscribedAudioCodec)
+}
+
+var _ DynacastManagerListener = (*DynacastManagerListenerNull)(nil)
+
+type DynacastManagerListenerNull struct {
+}
+
+func (d *DynacastManagerListenerNull) OnDynacastSubscribedMaxQualityChange(
+	subscribedQualities []*livekit.SubscribedCodec,
+	maxSubscribedQualities []types.SubscribedCodecQuality,
+) {
+}
+func (d *DynacastManagerListenerNull) OnDynacastSubscribedAudioCodecChange(
+	codecs []*livekit.SubscribedAudioCodec,
+) {
+}
+
+// -----------------------------------------
+
+type DynacastManager interface {
+	AddCodec(mime mime.MimeType)
+	HandleCodecRegression(fromMime, toMime mime.MimeType)
+	Restart()
+	Close()
+	ForceUpdate()
+	ForceQuality(quality livekit.VideoQuality)
+	ForceEnable(enabled bool)
+
+	NotifySubscriberMaxQuality(
+		subscriberID livekit.ParticipantID,
+		mime mime.MimeType,
+		quality livekit.VideoQuality,
+	)
+	NotifySubscription(
+		subscriberID livekit.ParticipantID,
+		mime mime.MimeType,
+		enabled bool,
+	)
+
+	NotifySubscriberNodeMaxQuality(
+		nodeID livekit.NodeID,
+		qualities []types.SubscribedCodecQuality,
+	)
+	NotifySubscriptionNode(
+		nodeID livekit.NodeID,
+		codecs []*livekit.SubscribedAudioCodec,
+	)
+	ClearSubscriberNodes()
+}
+
+var _ DynacastManager = (*dynacastManagerNull)(nil)
+
+type dynacastManagerNull struct {
+}
+
+func (d *dynacastManagerNull) AddCodec(mime mime.MimeType)                          {}
+func (d *dynacastManagerNull) HandleCodecRegression(fromMime, toMime mime.MimeType) {}
+func (d *dynacastManagerNull) Restart()                                             {}
+func (d *dynacastManagerNull) Close()                                               {}
+func (d *dynacastManagerNull) ForceUpdate()                                         {}
+func (d *dynacastManagerNull) ForceQuality(quality livekit.VideoQuality)            {}
+func (d *dynacastManagerNull) ForceEnable(enabled bool)                             {}
+func (d *dynacastManagerNull) NotifySubscriberMaxQuality(
+	subscriberID livekit.ParticipantID,
+	mime mime.MimeType,
+	quality livekit.VideoQuality,
+) {
+}
+func (d *dynacastManagerNull) NotifySubscription(
+	subscriberID livekit.ParticipantID,
+	mime mime.MimeType,
+	enabled bool,
+) {
+}
+func (d *dynacastManagerNull) NotifySubscriberNodeMaxQuality(
+	nodeID livekit.NodeID,
+	qualities []types.SubscribedCodecQuality,
+) {
+}
+func (d *dynacastManagerNull) NotifySubscriptionNode(
+	nodeID livekit.NodeID,
+	codecs []*livekit.SubscribedAudioCodec,
+) {
+}
+func (d *dynacastManagerNull) ClearSubscriberNodes() {}
+
+// ------------------------------------------------
+
+type dynacastQualityListener interface {
+	OnUpdateMaxQualityForMime(mimeType mime.MimeType, maxQuality livekit.VideoQuality)
+	OnUpdateAudioCodecForMime(mimeType mime.MimeType, enabled bool)
+}
+
+var _ dynacastQualityListener = (*dynacastQualityListenerNull)(nil)
+
+type dynacastQualityListenerNull struct {
+}
+
+func (d *dynacastQualityListenerNull) OnUpdateMaxQualityForMime(
+	mimeType mime.MimeType,
+	maxQuality livekit.VideoQuality,
+) {
+}
+
+func (d *dynacastQualityListenerNull) OnUpdateAudioCodecForMime(
+	mimeType mime.MimeType,
+	enabled bool,
+) {
+}
+
+// ------------------------------------------------
+
+type dynacastQuality interface {
+	Start()
+	Restart()
+	Stop()
+
+	NotifySubscriberMaxQuality(subscriberID livekit.ParticipantID, quality livekit.VideoQuality)
+	NotifySubscription(subscriberID livekit.ParticipantID, enabled bool)
+
+	NotifySubscriberNodeMaxQuality(nodeID livekit.NodeID, quality livekit.VideoQuality)
+	NotifySubscriptionNode(nodeID livekit.NodeID, enabled bool)
+	ClearSubscriberNodes()
+
+	Replace(
+		maxSubscriberQuality map[livekit.ParticipantID]livekit.VideoQuality,
+		maxSubscriberNodeQuality map[livekit.NodeID]livekit.VideoQuality,
+	)
+
+	Mime() mime.MimeType
+	RegressTo(other dynacastQuality)
+}
+
+var _ dynacastQuality = (*dynacastQualityNull)(nil)
+
+type dynacastQualityNull struct {
+}
+
+func (d *dynacastQualityNull) Start()   {}
+func (d *dynacastQualityNull) Restart() {}
+func (d *dynacastQualityNull) Stop()    {}
+func (d *dynacastQualityNull) NotifySubscriberMaxQuality(subscriberID livekit.ParticipantID, quality livekit.VideoQuality) {
+}
+func (d *dynacastQualityNull) NotifySubscription(subscriberID livekit.ParticipantID, enabled bool) {}
+func (d *dynacastQualityNull) NotifySubscriberNodeMaxQuality(nodeID livekit.NodeID, quality livekit.VideoQuality) {
+}
+func (d *dynacastQualityNull) NotifySubscriptionNode(nodeID livekit.NodeID, enabled bool) {}
+func (d *dynacastQualityNull) ClearSubscriberNodes()                                      {}
+func (d *dynacastQualityNull) Replace(
+	maxSubscriberQuality map[livekit.ParticipantID]livekit.VideoQuality,
+	maxSubscriberNodeQuality map[livekit.NodeID]livekit.VideoQuality,
+) {
+}
+func (d *dynacastQualityNull) Mime() mime.MimeType             { return mime.MimeTypeUnknown }
+func (d *dynacastQualityNull) RegressTo(other dynacastQuality) {}