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gamma4scanimage(1)	 SANE Scanner Access Now Easy	    gamma4scanimage(1)

NAME
       gamma4scanimage - create	a gamma	table for scanimage

SYNOPSIS
       gamma4scanimage gamma [shadow [highlight	[maxin [maxout]]]]

DESCRIPTION
       The  tool  gamma4scanimage creates a gamma table	in the format expected
       by scanimage. You can define a gamma, a shadow and a  highlight	value.
       You also	can specify the	size (maxin) and maximum output	value (maxout)
       of the gamma table.

       gamma  is a floating point value, neutral value being 1.0. If the value
       is larger than 1.0 then the image is brighter.

       shadow defines the minimum input	value that is necessary	to  create  an
       output  value  larger  than  zero.   shadow  has	 to  be	 in  the range
       [0..maxin].  Its	default	value is 0.

       highlight defines the maximum input value that produces an output value
       smaller than maxout.  highlight must be in  the	range  [0..maxin]  and
       larger  than  shadow.  Its default value	is the same as maxin (16383 if
       not set).

       maxin defines the size of the gamma table.  The	size  depends  on  the
       scanner/backend.	 If the	scanner	uses 8 bit gamma input then maxin must
       be  set	to  255,  1023 for 10 bits, 4095 for 12	bits, and 16383	for 14
       bits. The default is 16383.  To find out	what value maxin  has  to  be,
       call  scanimage(1)  with	 a  very large gamma table [0]0-[99999]255 and
       scanimage(1) will print an error	message	with the  needed  gamma	 table
       size.

       maxout  defines	the maximum output value. Take a look at the output of
       scanimage -h to find out	what maxout must be. The default value is 255.

EXAMPLE
       scanimage --custom-gamma=yes --gamma-table `gamma4scanimage 1.8 0 11500
       16383 255` >image.pnm

SEE ALSO
       sane(7),	scanimage(1)

AUTHOR
       Oliver Rauch

EMAIL-CONTACT
       Oliver.Rauch@Rauch-Domain.DE

				  10 Jul 2008		    gamma4scanimage(1)

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