Currently the ORTC API includes parameters.encodings[j].minQuality, which is defined as follows:
minQuality of type double, defaulting to 0
Never send less than this quality. 1.0 = maximum attainable quality. For scalable video coding, this parameter is only relevant for the base layer. This parameter is ignored in an RTCRtpReceiver object.
Can an application use parameters.encodings[j].minQuality to advise the browser when to drop a simulcast or SVC stream? How does this relate to parameters.degradationPreference?
This issue was discussed at the W3C WEBRTC WG meeting on January 14, 2015. Slides and minutes:
Fix for Issue #351