An API that configures WebRTC encoders to scale input frames if they are greater than the specified maxWidth and maxHeight. This API is similar to scaleResolutionDownBy except that resolution constraints are expressed in absolute terms (e.g. 640x360) as opposed to relative terms (e.g. scale down by 2), avoiding race conditions related to changing input frame size on the fly.
Allows web apps dynamically adjust video track resolution to match what the app wants to send (saving on performance) in a race-free way, avoiding what could otherwise result in user visible glitches at the remote endpoint. See https://github.com/w3c/webrtc-extensions/issues/159 and discussion at https://www.youtube.com/watch?v=SDKG463dvfI&t=1h11m16s.