Re: [rtcweb] Additional requirement - audio-only communication
"Timothy B. Terriberry" <tterriberry@mozilla.com> Fri, 26 August 2011 00:00 UTC
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Date: Thu, 25 Aug 2011 17:01:40 -0700
From: "Timothy B. Terriberry" <tterriberry@mozilla.com>
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Cc: "rtcweb@ietf.org" <rtcweb@ietf.org>, public-webrtc@w3.org
Subject: Re: [rtcweb] Additional requirement - audio-only communication
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Justin Uberti wrote: > I think it makes sense for the browser to emit capabilities, which could I agree there's clearly some gaps here that need to be filled. > then be used by the web app to generate a SDP offer or answer. This > The original problem that started this email is one specific example - > if the callee application wants to only receive audio, the application > can generate an audio-only SDP based on the offer, the browser I think the Harald's original problem was the other way around: the _caller_ wants to only receive audio, and needs to generate an SDP _offer_ that says that, even if the browser is capable of receiving video. I don't think that invalidates your point, though. > capabilities, and the desired app behavior - without any new APIs in the > browser. But I'm not sure what you mean by "without any new APIs"... in your approach, something has to be able to enumerate the capabilities in sufficient detail for the webapp to generate SDP by itself. I don't think there are any existing APIs that go that far. You also need an API to tell the browser what to actually do. The current PeerConnection approach is passing in the offer or the answer. If you're generating the answer, you need some way to tell your browser what you answered. For the "please don't send me video" case this is not an issue... it'll simply never arrive. If you want to change what the local browser is sending out, however, then it is. I do agree it eliminates the need for an API to tell the browser what kind of SDP to generate, but it also seems like it imposes a pretty big burden on application developers: even if you keep the currently-proposed PeerConnection ability to generate SDP as the "simple API", the moment you want to do something slightly more complex, you have to add code to generate the appropriate SDP, which necessarily involves figuring out all the capabilities of the various browsers on various platforms. Maybe I'm naive in thinking that seems like an awful lot of work just to say, "Please don't send me video."
- Re: [rtcweb] Additional requirement - audio-only … Randell Jesup
- Re: [rtcweb] Additional requirement - audio-only … Matthew Kaufman
- Re: [rtcweb] Additional requirement - audio-only … Dzonatas Sol
- Re: [rtcweb] Additional requirement - audio-only … Justin Uberti
- Re: [rtcweb] Additional requirement - audio-only … Timothy B. Terriberry
- Re: [rtcweb] Additional requirement - audio-only … Justin Uberti
- Re: [rtcweb] Additional requirement - audio-only … Stefan Håkansson LK
- Re: [rtcweb] Additional requirement - audio-only … Justin Uberti
- Re: [rtcweb] Additional requirement - audio-only … Stefan Håkansson LK
- Re: [rtcweb] Additional requirement - audio-only … Justin Uberti
- Re: [rtcweb] Additional requirement - audio-only … Stefan Håkansson LK
- Re: [rtcweb] Additional requirement - audio-only … Bernard Aboba
- Re: [rtcweb] Additional requirement - audio-only … Dzonatas Sol
- Re: [rtcweb] Additional requirement - audio-only … Randell Jesup
- Re: [rtcweb] Additional requirement - audio-only … Justin Uberti
- Re: [rtcweb] Additional requirement - audio-only … Stefan Håkansson LK
- Re: [rtcweb] Additional requirement - audio-only … Bernard Aboba
- Re: [rtcweb] Additional requirement - audio-only … Stephan Wenger
- Re: [rtcweb] Additional requirement - audio-only … Bernard Aboba