[sane-devel] ScanJet 7450C, avision-2003-02-08-1127-sane-1.0.10.patch, Redhat 8.0 - inverted images

[TomF]

On Mon, 10 Feb 2003 23:07:37 +0100 (CET)
Rene Rebe <rene.rebe at gmx.net> wrote:

> Hi.
> 
> On: Mon, 10 Feb 2003 13:06:27 -0800,
>     TomF <TomF at sjpc.org> wrote:
> 
...
> > 
> > Changing /dev/scanner to link to /dev/usb/scanner0 did not work, so
> > I changed it back to the Redhat 8.0 default:  -> /dev/sgf
> 
> The kernel's scanner driver is not used for the USB Avision scanners
> (so /dev/usb/scanner* is not the right device-node).
> 
> Insead the hpusbscsi driver is used to emulate a scsi-device.


How can I determine what driver is being used?  How can I configure the
correct driver?  I combined the information from several web sites to
do the configuration, but I did not see anything about hpusbscsi related
to the avision scanners.

> 
> > After I rebooted, scanimage worked, but produced a negative image.  
> 
> What do you mean with "negative" image? You mean it is "inverted"?
> Which scanmode (lineart, dithered, gray, color) do you use?

Yes,  a negative image is an inverted image, i.e. black and white are
interchanged.  I tried several scanmodes, and finally found that I could
get a positive, non-inverted image using lineart mode.  I sent another
note about this earlier today.

With scanmode gray, at one point I got black on gray images, i.e., the
text was black and the background, that should have been white. was
gray.

> 
> > I installed xsane-0.84-8.i386.rpm, but it looked for libraries in
> > /usr/lib while 1.0.10 had put them in /usr/local/lib.  I put links
> > in/usr/lib to resolve this.
> > 
> > xsane worked, but also produced negative images.  I was thrashing
> > around trying to get sane working before I found out about the
> > patch, and I may have changed something and forgot to record the
> > change.
> > 
> > It looks like I need a tutorial that describes how to pruduce plain
> > black and white images.  Where could I find one?


I would still like to find a tutorial.  Do you know where I could find
one?


> 
> - René
> 
> --  
> René Rebe - Europe/Germany/Berlin
> e-mail:   rene.rebe at gmx.net, rene at rocklinux.org
> web:      www.rocklinux.org, drocklinux.dyndns.org/rene/
> 
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