Re: [rtcweb] Making progress on the signaling discussion (NB: Action items enclosed!)

Stefan Håkansson LK <stefan.lk.hakansson@ericsson.com> Wed, 05 October 2011 12:48 UTC

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Date: Wed, 05 Oct 2011 14:51:31 +0200
From: Stefan Håkansson LK <stefan.lk.hakansson@ericsson.com>
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Subject: Re: [rtcweb] Making progress on the signaling discussion (NB: Action items enclosed!)
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On 2011-10-05 12:03, Tim Panton wrote:
> It seems to me that by calling WebRTC.SDP.answerFor() - getting the
> native code
> to do the 'compatibility matching' you've lost quite a lot of influence
> over the selection process.
> Lets say this is a conference app on an android phone - and lets say
> that the phone supports
> h 261, h263 and h264 but only has hardware accel for h264....

To me it seems that the browser (at least the one integrated by the 
device manufacturer) has a much greater chance of knowing what codecs 
are HW accelerated than the application - or do you expect a large 
database where device, version, OS-version, browser, browser version 
etc. is stored?

My preference would rather be that the app hints (as Tim proposed in 
<http://lists.w3.org/Archives/Public/public-webrtc/2011Oct/0004.html>), 
the browser proposes (by some kind of offer where the codecs are listed 
in preference order). If the offers are available to the application 
(for transport to the other end) it can override it there are objections.

Stefan