[asterisk-dev] how does a channel driver know the result of codec negotiation ?

[Luigi Rizzo]

On Fri, Oct 12, 2007 at 08:17:03PM +0200, Kevin P. Fleming wrote:
> Luigi Rizzo wrote:
> 
> > because typically you cannot afford to do video transcoding in
> > the middle box.
> > So if the caller tells "i can do H261 | H263 | MPEG4" and the callee
> > can only decode say H263, the caller still has no idea of what
> > format to use. For incoming streams it is not much of a problem - if
> > you get one of your supported formats you switch to that on the
> > first incoming frame. But for outgoing data you have no clue...
> 
> This situation is in no way unique to video; users with non-transcodable
> (or expensively transcodable) audio formats have the same problem.

i know - didn't want to make the story too long :)
(i suppose it is also a problem to pass the information across
a chain of asterisks)

> Until this issue is solved in Asterisk in some architecturally-proper
> way, then it will be a problem for video formats as well. The way

ok will keep in mind. Any idea of how other PBX address this issue ?

cheers
luigi