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Re: [rtcweb] Constraints on a track in a a given PC

From: Harald Alvestrand <harald@alvestrand.no>
Date: Fri, 20 Sep 2013 15:14:01 +0200
Message-ID: <523C4A19.9010706@alvestrand.no>
To: public-webrtc@w3.org
On 09/20/2013 03:01 PM, Jim Barnett wrote:
> Yes, you're right.  I'd forgotten that.  But applyConstraints can be called at any time, and always replaces any existing constraints with the newly specified ones. We can certainly define 'output' constraints for Track and use applyConstraints to apply them.  Isn't the problem renegotiation or inefficiency? If you call addStream with stream-level constraints and then applyConstraints to tweak the constraints at the Track-level,  the Track-level constraints might force an immediate renegotiation, which would be ugly.  Conversely, if you call applyConstraints first,  addStream's constraints might overwrite them.  Could we handle this by prioritizing Track constraints above the addStream constraints?

The only thing that happens when the UA notices that (re)negotiation is 
needed is that it fires a negotiationneeded event.

No negotiation happens until the Javascript actually calls the 
negotiation calls. The Javascript should be smart enough to not start 
doing that until it has finished tweaking constraints.

A bit convoluted, I know...
Received on Friday, 20 September 2013 13:13:03 UTC

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