--mode switch selects the basic mode of operation of the scanner valid choices are
Binary, Gray and Color. The Binary mode is black and white only, Gray will produce up to 256 levels of gray
and Color means 24 bit color mode. Some scanners will internally use 36 bit color,
the external interface however does only support 24 bits.
The --dropout option determines which color filters are used to scan in Binary mode. Valid choices are None, Red, Green and Blue.
The --halftoning switch selects the mode that is used in Binary mode. Valid options are None, Halftone A (Hard Tone), Halftone B (Soft Tone), Halftone C (Net Screen), Dither A (4x4 Bayer), Dither B (4x4 Spiral), Dither C (4x4 Net Screen), Dither D (8x4 Net Screen), Text Enhanced Technology, Download pattern A, and Download pattern B.
The --dropout switch selects the so called dropout color. Vald options are None, Red, Green and Blue. The default is None. The dropout color is used for monochrome scanning and selects the color that is not scanned. This can be used to e.g. scan an original with a colored background.
The --brightness switch controls the brightness of the scan. Valid options are the numbers from -3 to 3. The default is 0. The larger the brightness value, the brighter the image gets. If a user defined table for the gamma correction is selected, the brightness parameter is not available.
The --sharpness switch sets the sharpness of the image data. Valid options are the numbers from -2 to 2, with -2 meaning "Defocus", -1 "Defocus slightly", 0 "Normal", 1 "Sharpen slighly" and 2 "Sharpen".
The --gamma-correction switch controls the scanne internal gamma correction. Valid options are "Default", "User defined", "High density printing" "Low density printing" and "High contrast printing".
The --color-correction switch controls the scanner internal color correction function. Valid options are "No Correction", "Impact-dot printers", "Thermal printers", "Ink-jet printers" and "CRT monitors". The default is "CRT monitors".
The --resolution switch selects the resolution for a scan. Many EPSON scanners will scan in any resulution between the lowest and highest possible value. The list reported by the scanner can be displayed using the "--help -d epkowa" parameters to scanimage.
The --mirror option controls the way the image is scanned. By reading the image data from right to left the image is mirored. Valid options are "yes" and "no". The default is "no".
The --speed option can improve the scan speed in monochrome mode. Valid options are "yes" or "no", the "yes" option will speed up the scan if this option is supported.
The --auto-area-segmentation switch turns on the automatic area segmentation for monochrome scans. The scanner will try to determine which areas are text and which contain images. The image areas will be halftoned, and the text will be impoved. Valid options are "yes" and "no". The default is "yes".
The --gamma-table parameter can be used to download a user defined gamma table. The options takes 256 values from the range 0-255. In color mode this option equally affects the red, green, and blue channel.
The --red-gamma-table parameter can be used to download a user defined gamma table for the red channel. The valid options are the same as for --gamma-table.
The --green-gamma-table parameter can be used to download a user defined gamma table for the green channel. The valid options are the same as for --gamma-table.
The --blue-gamma-table parameter can be used to download a user defined gamma table for the blue channel. The valid options are the same as for --gamma-table.
The color correction coefficients --cct-1 --cct-2 --cct-3 ... --cct-9 will install color correction coefficients for the user defined color correction. Possible values are in the range -127..127.
The --preview option requests a preview scan. The frontend software automatically selects a low resolution. Valid options are "yes" and "no". The default is "no".
The --preview-speed options will increase the scan speed if this is supported by the scanner. Valid options are "yes" and "no", 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 aea. All parameters are specified in milimeters.
The --quick-format option lets the user select a scan area with predefined sizes. Valid parameters are "CD", "A5 portrait", "A5 landscape", "Letter", "A4" and "max". The default is "max", which selects the largest possible area.
The --source option selects the scan source. Valid options depend on the installed options. The default is "Flatbed".
The --auto-eject option will eject a page after scanning from the document feeder.
The configuration file /usr/local/etc/sane.d/epkowa.conf specifies the device(s) that the backend will use. The current version only supports one scanner per EPSON backend. Possible connection types are:
SCSI This is the default, and if nothing else is specified the backend software will open a given patch as SCSI device. More information about valid syntax for SCSI devices can be found in sane-scsi(5). PIP - Parallel Interface The parallel interface can be configured in two ways: An integer number starting at the beginning of a line will be interpreted as the IO address of the parallel port. To make it clearer that a configured IO address is a parallel port the port address can be preceded by the string "PIO". The PIO connection does not use a special device file in the /dev directory. USB A device file that is preceded by the string "USB" is treated as a scanner connected via the Universal Serial Bus. The correct special device file has to be created prior to using it with Sane. See the USB documentation for more information about how to set up the USB subsystem and the required device files.
/usr/local/lib/sane/libsane-epkowa.a The static library implementing this backend. /usr/local/lib/sane/libsane-epkowa.so The shared library implementing this backend (present on systems that support dynamic loading).
SANE_DEBUG_EPKOWA 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.
SANE_EPSON_CMD_LVL This allows to override the function or command level that the backend uses to communicate with the scanner. The function level a scanner supports is determined during the initialization of the device. If the backend does not recognize the function level reported by the scanner it will default to function level B5. Valid function levels are A1, A2, B1, B2, B3, B4, B5, B6, B7, B8 and F5. Use this feature only if you know what you are doing!
When used with "scanimage -T" the backend hangs after sucessfully completing the tests. It is necessary to powercycle the scanner to get the communication between backend and scanner going again.
Sometimes the scanner is not initialized correctly. The problem can be resolved by killing the program and restarting it again.
The backend may be used with EPSON scanners that are not yet listed under the list of supported devices. A scanner that is not recognized may default to the function level B3, which means that not all functions that the scanner may be capable of are accessible.
If the scanner is not even recognized as an EPSON scanner it is probably because the device name eported by the scanner is not in the correct format. Please send this information to the backend maintainer (email address is in the AUTHORS file).devices. A scanner that is not recognized may default to the function level B3, which means that not all functions that the scanner may be capable of are accessible.
If the scanner is not even recognized as an EPSON scanner it is probably because the device name eported by the scanner is not in the correct format. Please send this information to the backend maintainer (email address is in the AUTHORS file).
EPSON AVASYS Corporation