[Sugar-devel] GSoC Proposal: Multimedia Broadcasting

[Geza Kovacs]

On Fri, 2009-04-03 at 12:20 +0200, Jonas Smedegaard wrote:
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> On Fri, Apr 03, 2009 at 05:08:25AM -0400, Geza Kovacs wrote:
> >Since the objective is to broadcast an audio and video stream to the 
> >masses, I don't aim to use telepathy for this purpose; rather I aim to 
> >use an icecast server which runs on the broadcasting machine.
> 
> Please note that if you assume that the presenter machine is more 
> powerful than an XO then you should probably mention that pretty clearly 
> - - as that is probably not the default assumption.
> 

The overhead of having Icecast running on an XO-1 didn't seem anywhere
near as large as the overhead of the video encoding, though I did indeed
manage to get Icecast running on an XO-1 a few months ago with
relatively decent performance (though I was testing with only 5 viewers,
and wasn't performing the encoding on the same laptop). However, now
that I think of with 20 peers or so the overhead will likely become
significant, so it's probably best to have the most powerful laptop in
the classroom be designated as a server (and it would be advertising
this service via mDNS), and thus the IceCast server would only be run
locally if no such local streaming server is available. Therefore,
assuming the presence of at least one computer powerful enough to act as
an Icecast streaming server in the classroom and advertising itself as
such, broadcasting should be able to occur from even an XO-1.

> Oh, and are you subscribed to this list?  I cc'ed you this email but 
> forgot in another email I posted earlier today - I can repost forward if 
> you want, but it is safer if you mae sure to be subscribed here.
> 

I'm subscribed to sugar-devel. I did receive your email regarding
Gromit, and while I do indeed aim to use such an approach for
implementing annotation, I'd probably do so by the painting through GDK
instead, and since in this case displaying the annotation itself is
fairly trivial; instead the primary concern is how the annotation
information is to be transmitted since it obviously can't be in the same
stream as the video. I would probably put it as a separate stream on the
Icecast server, and store the point coordinates and annotation
information in a simple text file which would be read out and overlayed
over the video by the clients.

> (subscription is not mandatory here - I just personally come from the 
> Debian community where cc'ing is only done when explicitly requested - 
> so the blame is on me)
> 
> 
> Kind regards,
> 
>   - Jonas
> 
> - -- 
> * Jonas Smedegaard - idealist og Internet-arkitekt
> * Tlf.: +45 40843136  Website: http://dr.jones.dk/
> 
>   [x] quote me freely  [ ] ask before reusing  [ ] keep private
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