[asterisk-dev] AST_FRAME_DIGITAL

[critch]

On Thu, 2007-09-13 at 14:55 +0200, Klaus Darilion wrote:
> 
> Tilghman Lesher schrieb:
> > On Thursday 13 September 2007 05:14:40 Klaus Darilion wrote:
> >> Do you transcode IP packets from ulaw to alaw when sent from US to
> >> Europe? No - because it is digital.
> > 
> > Yes, you do, because it is a different codec.
> 
> Is this IPv7?

Someone must transcode ulaw to alaw or you don't get any usable audio
out the otherside. 

<joke>Could this be the communications problem we are having right
now</joke>

Any of the VoIP protocols would have told one side or the other what
codec they are using, and the otherside will have decided they can deal
with the incoming or not. That descision is based on knowing what it is
that they are to be getting on the wire.

Asterisk needs to treat the data it receives in a standard way because
we need to hand this information off to many differing technologies. So
having the base data converted into something that asterisk can then
pass around and know what it is, is important. 

How much effort is truly involved in splitting the original data stream
into the 3 constituent streams, and then remerging them? Is this really
too much load to handle? Yes it may seem unnecessary to you, but for the
same reasoning we shouldn't packetize the audio coming off of a
streaming channel driver then. Asterisk tries to handle everything as
generically as possible. Hand it packets of audio, and it will pass
those on to whatever channel driver needs it and then those drivers can
start from a simple known starting point and provide the proper output.
Get your data to simple known spec, and most channel drivers will be
able to get it out to the otherside.
-- 
critch <critch at basesys.com>