Dynacast: keep SVC tracks active while any quality is subscribed#1214
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Dynacast: keep SVC tracks active while any quality is subscribed#1214MaxHeimbrock wants to merge 1 commit into
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Port the SVC special case from client-sdk-js: for SVC codecs (VP9/AV1) all spatial layers ride in a single encoded stream and the SFU selects layers server-side, so any enabled quality in a SubscribedQualityUpdate must keep the whole encoding active instead of being matched per-layer. Adds an e2e test publishing VP9 L3T3_KEY that verifies the encoding stays active across quality requests, deactivates when the last subscriber leaves, and reactivates on resubscribe. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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ladvoc
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| let sub_options = TestRoomOptions::default(); | ||
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| let mut rooms = test_rooms_with_options([pub_options, sub_options]).await?; | ||
| let (pub_room, _pub_events) = rooms.remove(0); |
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nitpick: You can use rooms.pop() here.
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| let video_codec = publication.publish_options().video_codec; | ||
| // SVC codecs carry all spatial layers in one encoded stream. | ||
| let is_svc = matches!( |
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suggestion(non-blocking): Consider breaking this out into a const helper function.
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Stacked on #1213 (targets that branch; rebase to
mainonce it merges).What
Ports the SVC special case from client-sdk-js that #1003 didn't bring over: for SVC codecs (VP9/AV1) all spatial layers ride in a single encoded stream and the SFU selects layers server-side. When a
SubscribedQualityUpdatehas any quality enabled, the whole encoding must stay active, instead of matching qualities per encoding (which can deactivate the track, e.g. if the SFU enables only a quality that doesn't map to the rid-less encoding).JS reference:
setPublishingLayersForSenderinlivekit-client—if (isSVC) { if (qualities.some(q => q.enabled)) qualities.forEach(q => q.enabled = true); }, withisSVCCodec = vp9 || av1.Changes
LocalVideoTrack::set_publishing_layerstakesis_svcand applies the any-enabled rule.handle_subscribed_quality_updatederivesis_svcfrom the publication's codec (VP9/AV1), mirroringisSVCCodecin JS.test_dynacast_svc(VP9,L3T3_KEY): the single SVC encoding stays active across LOW/HIGH quality requests, deactivates when the last subscriber unsubscribes, and reactivates on resubscribe.SolidColorTrack::publish_with_optionstest helper for publishing with customTrackPublishOptions.Testing
All dynacast e2e tests pass against a local
livekit-server --dev:Observed SFU updates in the new test confirm the flow:
vp9:[Low=true, Medium=false, High=false]on a LOW request keeps the encoding ON;[Low=false, Medium=false, High=false]after unsubscribe turns it off.🤖 Generated with Claude Code