[sane-devel] Linotype X-ray Scanner

[Piernicola Oliva]

OK!!!!
It works! The option --custom-gamma=no solves the problem.
Thank you very much for your help.
Bye
Piernicola




On Tuesday 19 November 2002 22:57, Oliver Rauch wrote:
> Hello.
>
> You walked into a little trap with the default options of the
> sane-umax backend. By default the option "custom-gamma" is
> enabled what means that you have to send a gamma table
> or you have to disable the option "custom-gamma".
>
> When you do
> scanimage -d umax:/dev/sgb --source "Transparency Adapter" --resolution 300
> -l 30 -t 10 -x 175 -y 225 --depth 12 --custom-gamma=no
> then you should get good results.
>
> I will think about it if there is a chance to get rid of this trap.
>
> Bye
> Oliver
>
> Piernicola Oliva schrieb:
> > Hi,
> > I'm sorry for annoying you again, but I can't solve the problem.
> > I am using the command
> >
> >  scanimage -d umax:/dev/sgb --source Transparency Adapter --resolution
> > 300dpi -l 30 -t 10 -x 175 -y 225 --depth 12
> >
> > so I should obtain 12bit (in two byte) per channel per pixel.
> > But this is a picture of bytes (two for one channel) that I obtain:
> >
> > 00001001 - 10100000
> > 00001010 - 11110000
> > 00001000 - 00100000
> > 00001001 - 01100000
> > 00001010 - 10010000
> > 00001000 - 01100000
> > 00001001 - 10000000
> > 00001010 - 10110000
> > 00001000 - 10000000
> > 00001001 - 11100000
> > 00001010 - 11010000
> > 00001000 - 11000000
> > 00001001 - 11100000
> > 00001010 - 11110000
> > 00001000 - 10010000
> > 00001001 - 10100000
> > 00001010 - 11010000
> > 00001000 - 01100000
> > 00001001 - 10100000
> > 00001010 - 11000000
> > 00001000 - 00110000
> > 00001001 - 10000000
> > 00001010 - 10000000
> >
> > as you can see, they 8 bits values shifted of 4 bits.
> > what happens?
> > Am I doing something wrong?
> > Thank you
> > Pier
> >
> > On Saturday 16 November 2002 00:16, Oliver Rauch wrote:
> > > When you do not use any gamma table options it is ok.
> > >
> > > SANE supports images with a color depth of 8 or 16 bits/sample.
> > > A 12 bit sample does use 16 bits (2 bytes). The raw data of UMAX
> > > or Linotype scanners already is transfered from the scanner to the
> > > backend in this format. It is the raw format of the scanner.
> > >
> > > Best regards
> > > Oliver
> >
> > --
> >     \        name:     Piernicola OLIVA
> >    o/\_      address:  Universita' degli Studi di Sassari
> >   <\__,\               Struttura Dipartimentale di Matematica e Fisica
> >    ">   |              via Vienna 2, 07100, Sassari, Italia
> >     `   |    tel:      +39/079229486     (office)
> >          \             +39/3401450473    (mobile)
> >           \  fax:      +39/079229482
> >            \ e-mail:   oliva at uniss.it