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Re: [AVTCORE] [MMUSIC] BUNDLE: a single stream with multiple MIDs?

Iñaki Baz Castillo <ibc@aliax.net> Wed, 13 July 2016 08:55 UTC

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From: Iñaki Baz Castillo <ibc@aliax.net>
Date: Wed, 13 Jul 2016 10:53:55 +0200
Message-ID: <CALiegf=JJTPma0hZPtDk7=Qg0S5+LMQDjZv7xfz=BYqQw2=M=g@mail.gmail.com>
To: Jonathan Lennox <jonathan@vidyo.com>
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Cc: IETF AVTCore WG <avt@ietf.org>, mmusic <mmusic@ietf.org>
Subject: Re: [AVTCORE] [MMUSIC] BUNDLE: a single stream with multiple MIDs?
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2016-07-08 0:36 GMT+02:00 Jonathan Lennox <jonathan@vidyo.com>:
> The use case is where one m-line has a semantic of “always view this person” (my boss, say, or my customer); and another m-line has a semantic of “the current loudest speaker”.

Why is another m-line required for the "current loudest speaker" at all?

Who the current speaker is can be known by means of RTP header
extensions in client side. It can be also signaled by the server in
any custom way (out of the scope of SDP). Any of those mechanisms is
better than having yet another artificial m-line for that purpose.

I don't know CLUE, but assuming it pursuits similar aim than BUNDLE, I
think we should keep to a more declarative SDP syntax in which each
m-line represents a specific "media stream track" from a single
participant in the session, identified by a fixed MID (plus RID if the
sender switches to another media encoding).

If we can not even guarantee that, then SDP becomes extremely hard to
understand.


-- 
Iñaki Baz Castillo
<ibc@aliax.net>

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