[Asterisk-Users] Asterisk - Spandsp: fax header

[Peter Svensson]

On Wed, 18 May 2005, Steve Underwood wrote:

> Jean-Yves Avenard wrote:
> > On my Brother's fax machine (MFC-8820D) today, I've received 3 faxes: 
> > all of them at the top showed the caller Fax identity.
> > I received 2 faxes on Asterisk with spandsp, one from the same sender 
> > as earlier on the brother: there's nothing at the top.
> >
> > I wouldn't ask if it was obvious the data was inside the image, give 
> > me some credits for God's sake !
> 
> What you are describing is something I have never seen a FAX machine do.

> > Typically, when somebody is sending a fax on the Brother unit, once 
> > the connection has been established the identity of the fax caller is 
> > then displayed on the Brother's LCD (and this has nothing to do with 
> > PSTN CallerID), what is displayed on the LCD will be printed at the 
> > top of each pages. This is this behavior I'm trying to reproduce with 
> > Asterisk/Spandsp.
> 
> So you get the calling machine's number shown twice at the top of each 
> page? Once in this extra header, and once in the normal header sent as 
> part of the image? Weird. FAX machines don't normally do that. Does this 
> extra header overlay a part of the page, or does it make the page one 
> line longer?

Both the fax machines at work have a setting to add a header on received 
faxes. The information it adds is the page number, the sending machine id, 
name (if the sending machine id is in the speed dial list), and date+time. 
The original poster is not alone in having machines work this way.

> Spandsp puts the calling machine's number in one of the tag fields in 
> the TIFF headers. It puts several things in those tags - the name of the 
> software which generated the file (spandsp), the hostname of the 
> receiving computer, the far machine's ident, the far machine's maker and 
> model (if they can be identified). Programs like tiffdump will show that 
> information. Some image viewers also allow you to see it (don't ask me 
> which ones off hand).

Well, this should solve the original poster's problem. 

Peter