[sane-devel] Color balancing with a HP ScanJet 3200C

[stef]

Le Saturday 30 August 2008 22:58:53 Francesco Poli, vous avez écrit :
> On Sat, 30 Aug 2008 20:42:39 +0200 stef wrote:
> > Le Saturday 30 August 2008 18:05:38 Francesco Poli, vous avez écrit :
>
> [...]
>
> > > Am I failing to understand something?
> > > Can someone please suggest good {red,green,blue}-{gain,offset} values
> > > for the HP ScanJet 3200C ?
>
> [...]
>
> > 	Hello,
> >
> > 	if you enable advanced options in xsane, you will be able to tune gain
> > and offset manually to your liking.
>
> I used Xsane long ago, but now I am not able to use it in the present
> case, since the scanner is connected to a box with no X11, no screen,
> no keyboard, no mouse.  I only access the box through SSH.
>
> That's why I wanted to use command-line tools.
> I hope it's possible to obtain decent scans without X11...
>
> > BTW does the scanner gives good scans under
> > windows ?
>
> I don't know: last time I used that scanner under Windows was back in
> 1999 or 2000, I think.
> I hope Windows is not necessary to make SANE work under GNU/Linux...

	Hello,

	there are command lines options to tune gain and offset. You can use a script 
to try various values until you find a good combination. For me 'good' 
offsets are in the [1-3] range, while gains are in [2-10].
	Having the scanner tested under windows would tell me if the calibration code 
has to tweaked, or that the sensor is aging and giving wrong colors.

Regards,
	Stef