[asterisk-dev] Look ma, no audio

[Johansson Olle E]

Friends,

I'm finally able to place calls in Asterisk without audio. Asterisk  
SVN trunk now supports audio-less calls. It's taken a lot of hours of  
fixes and testing. So why do I bother with this kind of calling?

The reason is that I've been working with services for deaf and  
hearing impaired people. For some of the calls, video and text  
communication is enough. Why bother with audio if you can't hear it  
anyway?

Now, the issue I wanted to alert you about. I have made sure that this  
audio-less calling in SIP works and that SIP calls still work as  
normal with audio and audio+video and audio+text. I had to change some  
core parts to fix it. I haven't tested svn trunk with all other  
channel combinations. Are there any situations depending on the fact  
that  Asterisk did fail when we had no audio codecs for the call? If  
so, those calls might not fail any more in svn trunk and will give you  
a new problem to solve :-)

We've also worked a lot with videocaps today. Videocaps now have  
preferences for video codecs, like svn trunk has for audio.

We also fixed an issue with T.140 negotiation that confused Asterisk  
into believing that the T.140 rtp channel was used for H.264 video.  
That doesn't happen any more, but the fix was ugly. We do have a lot  
of issues in the way we parse the SDP that needs to be fixed with a  
more complete rewrite, so that we do parse each media part separately  
and respond properly for each media stream.

Please test both svn trunk and videocaps!

/O