[asterisk-users] fax support

[Olle E Johansson]

22 feb 2007 kl. 10.05 skrev Gordon Henderson:

> On Thu, 22 Feb 2007, Rilawich Ango wrote:
>
>> Hi all,
>> I have read many forums and discussion groups talking about fax
>> support in asterisk. Some of  them conclude that asterisk doesn't
>> support fax.  However, some of them conclude that there is no
>> relationship between fax and asterisk as asterisk will only pass the
>> fax signal to the fax machine.  I have tried the fax in asterisk
>> before but failed.  Anyone can give me some guideline how to make fax
>> support with asterisk?
>
> Search the archives for some scripts I posted a few weeks ago.
>
> But, as shipped, asterisk doesn't have native fax support, but it  
> can be patched in via the spandsp code, giving you 2 new  
> applications: RxFax and TxFax. You can plumb an incoming answered  
> call to RxFax and it will decode the incoming fax stream into a  
> TIFF file which you can then process as required.
>
> Asterisk does have the capability to listen to the incoming line  
> for the fax startup tones though, so you can use this as part of an  
> auto-attendant dialplan script to answer the line, listen for fax,  
> if fax, then call RxFax or connect it to an outgoing analogue port  
> with a real fax machine on it, or if not, play a message (if you  
> know the extension, dial it now, etc.).
>
> You really want the incoming stream to be a PSTN line though,  
> trying to encode an analogue fax call over the interweb is  
> "problematic" and prone to failure. If going down that route, I'd  
> get your DID supplier to do the fax to email conversion for you.  
> (Theres a plethora of them in the UK, don't know about elswhere  
> though)

And for fax over VOIP, sometimes called FOIP, Asterisk 1.4.x supports  
T.38 passthrough. However, the 1.4.0 release
is buggy, so either use 1.4 from subversion or wait for 1.4.1.

/O