This adds a new encoding parameter to WebRTC allowing the app to say which resolution it wants to send in absolute terms ("send 360p") instead of relative terms ("downscale by 2" + frame is 720p), avoiding race conditions when the track dynamically changes size.
Example use case is sending {360p, 720p} simulcast and when dynamically disabling the 720p layer also adjusting the track size to 360p in order to avoid expensive effects processing in 720p when only 360p is sent.
WebKittens
@youennf
Title of the proposal
WebRTC extensions, section scaleResolutionDownTo
URL to the spec
https://w3c.github.io/webrtc-extensions/#dom-rtcrtpencodingparameters-scaleresolutiondownto
URL to the spec's repository
No response
Issue Tracker URL
No response
Explainer URL
No response
TAG Design Review URL
No response
Mozilla standards-positions issue URL
https://github.com/mozilla/standards-positions/issues/1071
WebKit Bugzilla URL
No response
Radar URL
No response
Description
This adds a new encoding parameter to WebRTC allowing the app to say which resolution it wants to send in absolute terms ("send 360p") instead of relative terms ("downscale by 2" + frame is 720p), avoiding race conditions when the track dynamically changes size.
Example use case is sending {360p, 720p} simulcast and when dynamically disabling the 720p layer also adjusting the track size to 360p in order to avoid expensive effects processing in 720p when only 360p is sent.
See https://www.w3.org/2024/08/27-webrtc-minutes.html#t06 where this was discussed and approved by the W3C WebRTC WG.