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gamma4scanimage(1) [centos man page]

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

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 is 1.0, if the value is larger than 1.0 then the image gets 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 has to be in the range [0..maxin], highlight has to be 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 bits gamma input then maxin has to be set to 255, for 10 bits 1023, for 12 bits 4095, for 14 bits 16383. The default is 16383. To find out what value maxin has to be call scanimage with a very large gamma table [0]0-[99999]255 then scanimage prints an error message with the needed size of the gamma table. maxout defines the maximum output value. Take a look at the output of scanimage -h to find out what maxout has to be. The default value is 255. EXAMPLE
scanimage --custom-gamma=yes --gamma-table `gamma4scanimage 1.8 0 11500 16383 255` >image.pnm SEE ALSO
scanimage(1) AUTHOR
Oliver Rauch EMAIL-CONTACT Oliver.Rauch@Rauch-Domain.DE 10 Jul 2008 gamma4scanimage(1)

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sane-sceptre(5) 					   SANE Scanner Access Now Easy 					   sane-sceptre(5)

sane-sceptre - SANE backend for SCEPTRE scanners DESCRIPTION
The sane-sceptre library implements a SANE (Scanner Access Now Easy) backend that provides access to Sceptre flatbed scanners. This backend should be considered beta-quality software! Please report any strange behavior to the maintainer of the backend or to the SANE mailing list. At present, only one scanner is known to work with this backend: Model Connection Type --------------------------- ------------------- Sceptre VividScan S1200 SCSI The make of this scanner is KINPO, so other scanners from that manufacturer may also work (eg. the S600). OPTIONS
The options the backend supports can either be selected through command line options to programs like scanimage or through GUI elements in xscanimage or xsane. Valid command line options and their syntax can be listed by using scanimage --help -d sceptre Scan Mode --mode selects the basic mode of operation of the scanner valid choices are Lineart, Halftone, Gray and Color. The Lineart and Halftone mode are black and white only (1 bit). Gray will produce 256 levels of gray (8 bits). Color will produce a 24 bits color image. The scanner supports 30 bits internally but it only exports 24. --resolution selects the resolution for a scan. The scanner can do several resolutions between 50 and 1200. --halftone-pattern selects the pattern mode that is used in Halftone mode. Valid options are 1, 2, 3 and 4. --gamma-correction controls the scanner internal gamma correction. Valid options are "Default", "User defined", "High density printing" "Low density printing" and "High contrast printing". --custom-gamma (color mode only) allows the user to specify a gamma table (see the next 3 parameters). --red-gamma-table (color mode only) can be used to download a user defined gamma table for the red channel. The table must be 256 bytes long. --green-gamma-table (color mode only) can be used to download a user defined gamma table for the green channel. The table must be 256 bytes long. --blue-gamma-table (color mode only) can be used to download a user defined gamma table for the blue channel. The table must be 256 bytes long. --threshold sets the threshold for black and white pixels in lineart mode. Possible values are from 0 (darker) to 255 (lighter). --preview requests a preview scan. The resolution used for that scan is 30 dpi and the scan area is the maximum allowed. The scan mode is user selected. The default is "no". The geometry options -l -t -x -y control the scan area: -l sets the top left x coordinate, -t the top left y coordinate, -x selects the width and -y the height of the scan area. All parameters are specified in millimeters by default. CONFIGURATION FILE
The configuration file /etc/sane.d/sceptre.conf supports only one information: the device name to use (eg /dev/scanner). FILES
/usr/lib64/sane/libsane-sceptre.a The static library implementing this backend. /usr/lib64/sane/ The shared library implementing this backend (present on systems that support dynamic loading). ENVIRONMENT
SANE_DEBUG_SCEPTRE If the library was compiled with debug support enabled, this environment variable controls the debug level for this backend. E.g., a value of 128 requests all debug output to be printed. Smaller levels reduce verbosity. LIMITATIONS
Resolutions The windows TWAIN driver can be set to any resolution between 50 to 1200 (excluding software interpolation). This backend cannot. Only a handful of resolution are available, although they should be numerous enough. BUGS
None known. SEE ALSO
sane-scsi(5), scanimage(1), xscanimage(1), xsane(1), sane(7) AUTHOR
The package is actively maintained by Frank Zago. 11 Jul 2008 sane-sceptre(5)
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