[asterisk-dev] Getting negotiated formats

[Lorenzo Miniero]

Hi all,

I have a doubt regarding a feature that I couldn't exploit, even though 
Kevin Flaming stated was there.

Since I'm working on a remote videomixer for MeetMe, I need to know 
which formats have been negotiated when a user joins a conference, e.g. 
if the user will be using H.261, h263 and so on, to setup an adequate 
leg towards the external mixer and to forward the user the composed mix 
in a format it understands. The only way I have been able to do it so 
far is by waiting for the user to send its first video frame, and then 
look at its subclass: this of course is an all but the perfect solution, 
since a user could never send any video frame at all.
However, on the asterisk-dev ML I have been told that it should however 
be possible to get the same information by just accessing some fields in 
the ast_channel structure. By deduction, I supposed this information was 
stored as a bit mask in readformat and writeformat, but I couldn't get 
any coherent info from there in the scenarios I tried. Do you know if 
there actually is a way to achieve this, or if support for this is 
incomplete?

Thanks in advance, hope to hear you soon,

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