Re: Some ideas on SVC support in WebRTC 1.0 (Take 2)

Harald said:

"I think this would be unwise.

There are 2 parameters - temporal scaling and spatial scaling. Calling a layer "temporal" or "spatial" implies that only one of these parameters varies from its base layer; it should (I think) be quite common to vary both."


[BA] There are other disadvantages as well:


b. Inability to vary the spatial scaling to the same extent as is possible for simulcast today.  This could prevent spatial scalability (supported in VP9 and AV1) from substituting for spatial simulcast in some applications.


c. Inability to support more sophisticated robustness schemes in the future.  The original design of RTCRtpRtxParameters and RTCRtpFecParameters (since removed from WebRTC 1.0) provided support for differential protection (e.g. applying RTX or FEC only to the base layer).