Re: [rtcweb] Additional requirement - audio-only communication

Justin Uberti <juberti@google.com> Fri, 26 August 2011 20:07 UTC

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From: Justin Uberti <juberti@google.com>
Date: Fri, 26 Aug 2011 16:07:52 -0400
Message-ID: <CAOJ7v-1j8PNgvUBqvwjUbB6SC4jykdnKad=18baf4uUeDdfsiQ@mail.gmail.com>
To: Bernard Aboba <bernard_aboba@hotmail.com>
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Subject: Re: [rtcweb] Additional requirement - audio-only communication
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It can, and in this case it would probably work fine. The browser will still
instantiate the machinery needs to receive video, since it doesn't know the
m=video line was removed, but assuming the remote side functions correctly,
this should not result in a noticeable problem.

However, other adjustments to the SDP will not be so benign, such as
changing the a=crypto lines, or payload ids, although they could be if the
offerer was informed of the updated description.

On Fri, Aug 26, 2011 at 1:06 PM, Bernard Aboba <bernard_aboba@hotmail.com>wrote;wrote:

>  [BA] Why can't the initiating application delete the m=video line from the
> SDP blob
> that the signaling callback receives, before sending it to the callee?
> Are we assuming
> that the SDP blob is opaque and can't be edited?
>
>
>  Stefan said:
>
> "What we really want is some way to either a) an API to tell the
> initiator browser to produce an offer with no m=video, or b) a way for
> the application to customize or generate the offer and feed it back to
> the browser. b) is definitely more complex, but a) could end up causing
> us to add a lot of knobs to the API.
>
>
> Stefan
> "
>
>
>
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>