Re: [webrtc-pc] "getParameters" and "setParameters" need more thorough specification

Subsets of the "current parameters" are affected by different methods: 

1. addTransceiver with sendEncodings can set rids, the number of encodings, and writeable encoding parameters on the sender.   This affects the SDP produced by createOffer/createAnswer. 

2. sender.setParameters() can reorder or remove codecs and can set writeable encoding parameters (but cannot change read-only parameters, the number of encodings or the sdpFmtpLine).  We say that setParameters cannot set the negotiation-needed flag, but do not say explicitly that setParameters does not affect the SDP produced by createOffer() and createAnswer().

3. setCodecPreferences() can reorder or remove codecs but cannot set the sdpFmtpLine.  This affects the SDP produced by createOffer/createAnswer. 

4. Calling setLocalDescription (for a receiver) or setRemoteDescription (for a sender) sets parameters from the SDP.

Can getParameters() can return a subset of the parameters, or does it only return a non-null result once setLocal (receiver) or setRemote (sender) is called?  If sender.getParameters() returns null before setRemoteDescription, can sender.setParameters() be called before setRemoteDescription? That would imply that calling getParameters after setParameters would not necessarily return the parameters that were set.  









-- 
GitHub Notification of comment by aboba
Please view or discuss this issue at https://github.com/w3c/webrtc-pc/issues/1116#issuecomment-292586778 using your GitHub account

Received on Friday, 7 April 2017 16:37:33 UTC