[webrtc-pc] Spec says scaleResolutionDownBy must default to 1, but browsers differ (#2535)

jan-ivar has just created a new issue for https://github.com/w3c/webrtc-pc:

== Spec says scaleResolutionDownBy must default to 1, but browsers differ ==
The [spec](https://w3c.github.io/webrtc-pc/#dom-rtcrtpencodingparameters-scaleresolutiondownby) says: _"By default, the sender will not apply any scaling, (i.e., scaleResolutionDownBy will be 1.0)"_.

This is correct in Firefox (78 using a [fiddle](https://fiddle.jshell.net/jib1/yvg81otc/45/) where `scaleResolutionDownBy` is commented out):
* Three videos of the same size

But incorrect in Chrome ([crbug 1088200](https://bugs.chromium.org/p/chromium/issues/detail?id=1088200)):
* One large, one medium, and one small video.

Unfortunately, the incorrect behavior is clearly a more _useful_ default, making it a web compat issue. I'm filing this spec issue for visibility and clarification of intent. Do we fix Chrome or change the spec? And if we change the spec, then to what?

cc @alvestrand @guidou

Please view or discuss this issue at https://github.com/w3c/webrtc-pc/issues/2535 using your GitHub account

Received on Saturday, 30 May 2020 18:46:55 UTC