Re: [hylafax-users] Scanner to fax resolution problem

[Aidan Van Dyk <aidan@xxxxxxxx>]

* Frank Millman <frank@xxxxxxxxxxxx> [090107 03:58]:
 
> So far everything works ok, with the exception that documents scanned on
> Fedora and faxed to Windows come out with a poor resolution. I am using the
> built-in xsane gui front end, but if I use the sane cli, I get the same
> result.

HylaFAX uses Ghostscript to "re-render" tiff images that aren't the
correct size/resolution/format for direct fax transmission.

 
> I also tried writing the image to a file, using -
> 
>     scanimage --mode Gray --resolution 200 --format tiff -x 215 -y 297 >
> /home/frank/test.tif
> 
> This is how I found out the file size. If I then do the following -
> 
>     sendfax -n -m -d 1234567 /home/frank/test.tif
> 
> it sends the fax ok, but with the same problem. 
> 
> I tried scanning with a resolution of 100 and 150. It creates a smaller file
> (though still much bigger than 137kb), but the background is very dark, so
> not acceptable. I don't know why that happens.
> 
> I don't know what else to try. Any suggestions will be much appreciated.

My guess is that the image isn't right for direct FAX (T.30) sending,
and the ghostscript middle-man is the culprit.

You can see the tiff2fax command executed in syslog if you turn up faxq
logging, and running it by hand (and with -x) will show you the GS
running to squash the bad-sized tiff to the right-sized tiff (and then
you can verify that it's the GS making the right-sized tiff look bad).

Another option would by to try and get SANE to scan to the right format,
I think your best bet is to try and get it to match:

Horizontal: RES of 204(pi), 1728 pixels wide *exactly*
Vertial:    RES of 196(pi), variable length (as long as your receiver accepts it,
                 otherwise around 2150 - 2300 pixels for letter/A4

a.

-- 
Aidan Van Dyk                                             aidan@xxxxxxxx
Senior Software Developer                          +1 215 825-8700 x8103
iFAX Solutions, Inc.                                http://www.ifax.com/

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