[sane-devel] Canon Lide 400: brightness/contras in xsane, but not in scanimage

[Frank Steiner]

In case someone finds this in Google having the same problem:
My application is scanning to PDF and I usually create tiff files
and convert them with "tiff2pdf -j" to generate compressed pdf
files.

Without the --brightness/--contrast options for the LIDE 400 this
is possible with "scanimage --format=tiff ..." and using "convert"
from the ImageMagick package, e.g.

convert -brightness-contrast 10x20 test.tiff test.tiff

However, creating PDFs from such converted tiffs results in very
slow scaling in e.g. okular compared to the pdfs created
straight from the tiff. This can be fixed with

tifftopnm test.tiff  | pnmtotiff - > test2.tiff
tiff2pdf -j test2.tiff > test2.pdf

cu,
Frank




Frank Steiner wrote:

> Hi,
> 
> just tried the Canon Lide 400 with sane-backends 1.1.1 and it works
> fine w.r.t. all the modes or resolutions. It is detected as
> pixma:04A91912_487637
> 
> But --brightness/--contrast are not shown as available options for
> this device (and rejected as "unrecognized option" when I try them).
> 
> In xsane, however, there are sliders for brightness and contrast
> that work and their settings are reflected in the scanned image.
> 
> So I wonder if sth. is missing in sane-backends to make these
> options available for the Canon Lide 400, or if xsane just simulates
> these with software and not by adjusting the scanner settings.
> 
> Using xsane is a workaround, but I used to run scanbd to make the
> buttons call scanimage with certain settings (resolutions/modes),
> so I'd really to continue using scanimage.
> 
> Is there a chance to get brightness/contrast options working with
> this scanner?
> 
> Thanks for your help!
> 
> cu,
> Frank
> 

-- 
Dipl.-Inform. Frank Steiner   Web:  http://www.bio.ifi.lmu.de/~steiner/
Lehrstuhl f. Bioinformatik    Mail: http://www.bio.ifi.lmu.de/~steiner/m/
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