[Asterisk-Users] some EICON Diva 4BRI questions

[Armin Schindler]

On Mon, 24 Apr 2006, Olivier Krief wrote:
> 2006/4/23, Armin Schindler <armin at melware.de>:
> >
> > On Sun, 23 Apr 2006, Olivier Krief wrote:
> > > 2006/4/21, Armin Schindler <armin at melware.de>:
> > > >
> > > >
> > > > But if you want to forward a call (which was already accepted by
> > Asterisk)
> > > > to another CAPI application, it is not possible. (Well, Eicon has a
> > > > special
> > > > driver which can do a lot of CAPI extensions, but I did not try this
> > yet).
> > > > So if you want to do that, I suggest using just chan-capi for
> > receiving
> > > > faxes and maybe another application for sending faxes.
> > > >
> > > > Armin
> > > >
> > > This is exactly the heart of my question : is it possible to "accept" a
> > call
> > > with capi-enabled Asterisk, detect it's a fax and "forward" it somehow
> > to a
> > > hardware-enforced fax application on the same server.
> > >
> > > Doing that you could get higher fax speeds and reliability and
> > interesting
> > > Asterisk features.
> >
> > Why do you think you will get higher fax speeds or reliability?
> > There is no difference in receiving a fax over CAPI between chan-capi
> > and any fax-software like capi4hylafax. Both use the same CAPI commands
> > with the use of the card's fax capabilities.
> 
> 
> I thought that receiving fax with Asterisk always meant to use one way or
> another, spandsp library.
> That's the reason why I thought fax-enabled boards provide higher fax speeds
> or reliability.
> (I don't mean using spandsp isn't reliable : I mean fax boards are said and
> "priced" to be more reliable and it's worth to evaluate the benefit of using
> them).
> 
> When writing "receiving a fax over CAPI", do you mean "receiving a fax over
> CAPI with Asterisk and processing it with spandsp" ?

When using a card with onboard DSPs (or even the software fax of AVM Fritz 
binary-only driver) you can do faxing with the CAPI interface. That means 
you don't get the audio data stream, you get the fax-data instead which can 
be save in a file.

In that case the application (Asterisk or anything else) don't need to do 
the fax processing, this is done by the driver (in case of AVM Fritz) or on 
the hardware in case of DSPs (like Eicon DIVA Server).

chan-capi supports this and if the CAPI driver/device supports fax over 
CAPI, you don't need anything like spandsp. That's what I mean with faxing 
over CAPI.

Armin