[Asterisk-video] Videomixing in MeetMe

[Lorenzo Miniero]

Hi all,

I just uploaded on the CONFIANCE webpage, http://confiance.sf.net/, the 
patch to enable videomixing and continuous presence in MeetMe. The patch 
enables such functionality both for our enhanced MeetMe (i.e. video 
sources are enabled/disabled through BFCP moderation) and for basic 
MeetMe rooms (the videoswitch console command I uploaded some time ago 
is used to enable/disable video sources). All the instructions needed to 
build and configure it are attached with the patch.

To provide such a feature MeetMe can make use of two videomixers:

	* the CONFIANCE VideoMixer we're writing (available on 
http://confiance.sf.net/);
	* the VideoMixer Sergio Garcia Murillo is writing (available via svn, 
svn co http://sip.fontventa.com/svn/mcu, needs xmlrpc-c 1.1).

You can choose which one to use by setting a value in the configuration 
file. You can even disable them both and still rely on basic 
videoswitching, if you're not interested in videomixing...

All is work in progress, so both Sergio and I would really appreciate 
any kind of feedback you'll be able to provide us.

I'll spend two words on my work, and I'll let Sergio speak of his own 
since I couldn't do it better than him. The CONFIANCE VideoMixer 
currently provides:

	* adaptive layouts according to how many active video sources are 
feeding the mix;
	* continuous presence for up to 8 users (this can be easily enhanced by 
adding new layouts in the code; if you look at the code, you'll see that 
creating and modifying layouts is really simple);
	* a static logo when no video sources are active;
	* support for H.261, H.263 and H.263+ (QCIF only for the moment).

Currently, only one global layout is available for all users in the same 
conference, but this will be changed in the future.

We tested it with many softphones, as:

	* Minisip, one the softphone we're enhancing to add XCON support, and 
which makes use of H.263+ as codec;
	* another custom client we're writing, making use of H.263 (JMF);
	* X-Lite 3.0, H.263;
	* Ekiga stable 2.0.x (H.261).

All work quite fine except Ekiga, since H.261 support in our videomixer 
is still quite buggy (probaby related to how we handle the H,261 payload 
header), and sometimes makes Ekiga crash. Any feedback upon this will be 
more than welcome!


If you're interested in knowing something more about the implementation 
details and/or how the videomixers have been integrated in MeetMe, feel 
absolutely free to ask.


Hope to hear you soon, regards,
Lorenzo

-- 
Lorenzo Miniero, Junior Researcher
Dipartimento di Informatica e Sistemistica
Università degli Studi di Napoli "Federico II"
Via Claudio 21 -- 80125 Napoli (Italy)
Phone: +390817683821 - Fax: +390817683816
Email: lorenzo.miniero at unina.it