[Asterisk-video] sip/iax2 h.264 video?

[Mihai Balea]

On Dec 19, 2006, at 3:36 AM, Tyler Daniel wrote:

> I read your earlier posts about lack of negotiation capabilities in  
> asterisk..  I guess I'm a little confused about the current state  
> of affairs..  Maybe you can enlighten me:  is any type of video  
> call using iax2 possible in any publicly available version of  
> asterisk?  If it's only possible using your 1.4 patches/hacks, are  
> those available anywhere?
As far as I can tell, you cannot negotiate a video codec with  
mainline Asterisk and IAX2. This makes it impossible to setup any  
video call. I'd be glad to hear from anybody who can prove me wrong -  
it is possible that I am missing something.

My patch is not publicly available.  I can send it to you out of band  
if you want... it is very limited in scope and ugly, but it works for  
us which means that if you use iaxclient, it can work for you too.   
I'm a bit reluctant to release it to the public, since it is not the  
best approach to the problem, it's just a quick hack.

>
> I've googled and found lots of vague comments that asterisk passes  
> through video with no option for transcoding, which is fine by  
> me... I assumed that this meant there is a way to do video, but  
> maybe only when using sip?  Also references to patches backported  
> to the 1.2 series that I have yet to find... very confusing.
Asterisk has been able to do video over SIP for quite a while now.  
This is due to the way SIP/SDP negotiate things. It somewhat works in  
1.2, but I'd advise you to stick with 1.4 for video.

There's no transcoding for video and I don't think there will be, at  
least not in the near future.  It is too CPU intensive and video  
codecs are usually proprietary which makes it a hassle to include in  
mainline asterisk... at least that's my take.

Mihai