----- Original Message -----
From: "Peter Saint-Andre" <[EMAIL PROTECTED]>
Newsgroups: gmane.network.jabber.standards-jig
To: "XMPP Extension Discussion List" <[email protected]>
Sent: Monday, June 09, 2008 2:29 PM
Subject: Re: UPDATED: XEP-0167 (Jingle RTP Sessions)
On 06/06/2008 1:23 PM, Jeff Muller wrote:
Just a quick question:
I didn't quite glean this from the spec and am not sure if it's been
discussed in this forum, but is there a way to associate two streams (or
two <content /> entities)? Typically, for a video "call", there are two
streams, audio and video. You want these two streams associated in the
client a) so that they can be presented in an associated way (camera and
speaker controls near each other), and b) so that they can be associated
for lip sync. Especially if there are two video streams (for example,
there's a document camera), you want to know which is the "main" stream
that goes (by default) in the main window with the audio controls. Or
for that matter, if you only want to allow one video stream, you know
which one to do a content-remove on.
Wouldn't the associated media simply be part of the same RTP session? Or
do you want the ability to associate media across RTP sessions?
I'm definitely not an RTP expert here. But from a quick web search... Isn't
each multimedia type limited to a separate RTP session? From what I read, a
session really just consists of the port pairs for the (single) RTP and
(single) RTCP streams. Maybe?
Or, is it to be inferred that for a single session, there can be at most
one entry for each content type, and that any others would be yet
another session (not sure I like that). I have no idea which approach
maps better to SIP.
No, I think you can have multiple entries per media type -- for example,
a room pan and a podium view for video from a conference.
That's what I would have hoped/expected. Although that poses another
interesting situation. In your example, either of those streams could be
associated with the audio, as opposed to a completely separate video stream.
So, lets say we combine your example, with also sending a auxiliary
audio/video stream (let's say, we're streaming a local multimedia file
that's a training video). How would we associate the speaker's voice stream
with the two in-room video views, and the training video's audio with the
video? I realize the is quite an elaborate scenario, but at least in terms
of protocol, we should be able to express it.
Also, it seems to me that, although "ringing" and "hold", would
typically be associated with a session, I could see how "mute" would be
associated with individual streams (<content/>). I may be in a
voice-video session, but temporarily want to mute only video, because I
need to pick my nose, or scratch an intimate area, or whatever, and then
un-mute again. Otherwise, how would session-mute be different than
session-hold? Perhaps <mute /> could include an optional "name" property
which, if present, specified the name of a particular <content />
entity???
That makes sense, I'll modify XEP-0167 accordingly.
Coolio!
Thanks for listening,
No, thank you! ;-)
Peter
--
Peter Saint-Andre
https://stpeter.im/
