| sane-genesys(5) | SANE Scanner Access Now Easy | sane-genesys(5) |
sane-genesys - SANE backend for GL646, GL841, GL843, GL847 and GL124 based USB flatbed scanners
The sane-genesys library implements a SANE (Scanner Access Now Easy) backend that provides access to USB flatbed scanners based on the Genesys GL646, GL841, GL843, GL847 and GL124 chips. At present, the following scanners are known to work with this backend:
This is stable software for supported models. But if you test new or untested scanners, keep your hand at the scanner's plug and unplug it, if the head bumps at the end of the scan area.
If you own a scanner other than the ones listed above that works with this backend, please let me know this by sending the scanner's exact model name and the USB vendor and device ids (e.g. from /proc/bus/usb/devices, sane-find-scanner or syslog) to the sane-devel mailing list. Even if the scanner's name is only slightly different from the models mentioned above, please let me know.
If you own a scanner that isn't detected by the genesys backend but has a GL646, GL841, GL843, GL847 or GL124 chipset, you can try to add it to the backend.
To give correct image quality, sheet fed scanners need to be calibrated using the calibration sheet sold with the scanner. To do calibration, you must insert this target in the feeder then start calibration either by passing the --calibrate option to scanimage or by clicking on the available 'calibrate' button in the 'advanced options' in a graphical frontend. The result of the calibration is stored in a file in the home directory of the user doing it. If you plug the scanner in another machine or use it with another account, calibration will have to be redone, unless you use the --calibration-file option. If no home directory is defined, USERAPPPROFILE will be used, then TMPDIR or TMP. If none of these directories exist, the backend will try to write in the current working directory. Flatbed scanners also make use of the calibration file as a cache to avoid calibration before each scan. Calibration file name is the name of the scanner model if only one scanner is detected. In the case of several identical model, the file name will be the name of the logical USB device name. The expiration time manages the time a calibration is valid in cache. A value of -1 means forever, 0 means no cache.
Additionally, several 'software' options are exposed by the backend. These are reimplementations of features provided natively by larger scanners, but running on the host computer. This enables smaller machines to have similar capabilities. Please note that these features are somewhat simplistic, and may not perform as well as the native implementations. Note also that these features all require that the driver cache the entire image in memory. This will almost certainly result in a reduction of scanning speed.
This backend needs libusb-0.1.6 or later installed, and hasn't tested in other configuration than a linux kernel 2.6.9 or higher. However, it should work any system with libusb where the SANE package can be compiled. For setting permissions and general USB information look at sane-usb(5).
The contents of the genesys.conf file is a list of usb lines containing vendor and product ids that correspond to USB scanners. The file can also contain option lines. Empty lines and lines starting with a hash mark (#) are ignored. The scanners are autodetected by usb vendor_id product_id statements which are already included into genesys.conf. "vendor_id" and "product_id" are hexadecimal numbers that identify the scanner.
Example (full and highly verbose output for gl646):
export SANE_DEBUG_GENESYS=255
Jack McGill for donating several sheetfed and flatbed scanners, which made possible to add support for them in the genesys backend:
Oliver Rauch
Henning Meier-Geinitz <henning@meier-geinitz.de>
Gerhard Jaeger <gerhard@gjaeger.de>
Stéphane Voltz <stef.dev@free.fr>
Philipp Schmid <philipp8288@web.de>
Pierre Willenbrock <pierre@pirsoft.dnsalias.org>
Alexey Osipov <simba@lerlan.ru> for HP2400 final support
Powersaving isn't implemented for gl646 based scanner. Dynamic (emulated from gray data and with dithering) isn't enabled for gl646 scanners. Hardware lineart is limited up to 600 dpi for gl847 based scanners, due to the way image sensors are built.
This backend will be much slower if not using libusb-1.0. So be sure that sane-backends is built with the --enable-libusb_1_0 option.
For the LiDE 200, the scanned data at 4800 dpi is obtained "as is" from sensor. It seems the windows driver does some digital processing to improve it, which is not implemented in the backend.
| 4 Jul 2012 |