sane-coolscan2 - SANE backend for Nikon Coolscan film scanners
The sane-coolscan2 library implements a SANE (Scanner
Access Now Easy) backend that provides access to Nikon Coolscan film
scanners. Some functions of this backend should be considered
beta-quality software. Most functions have been stable for a long
time, but of course new development can not and will not function properly
from the very first day. Please report any strange behaviour to the
maintainer of the backend.
At present, the following scanners are known to work with this
backend:
Model: Connection Type
--------------------------- -------------------
LS-30 (Coolscan III) SCSI
LS-2000 SCSI
LS-40 ED (Coolscan IV) USB
LS-4000 ED IEEE 1394
LS-8000 ED IEEE 1394
Please send mail to the backend author
(andras@users.sourceforge.net) to report successes or failures.
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
coolscan2:<interface>:<device>
where <interface> and <device> specify the device in question, as in
the configuration file (see next section). The -d parameter and its argument
can be omitted to obtain information on the first scanner identified. Use the
command
scanimage -L
to list all devices recognized by your SANE installation.
The options should be fully described by the description or
tooltips given by frontend. Here is a description of some of the most
important options, in the syntax with which they must be supplied to
scanimage:
- --frame
<n>
- This option specifies which frame to operate on, if a motorized film strip
feeder or APS adapter are used. The frame number <n> ranges
from 1 to the number of frames available, which is sensed each time the
backend is initialized (usually each time you start the frontend).
- --subframe
<x>
- This option shifts the scan window by the specified amount (default unit
is mm).
- --infrared=yes/no
- If set to "yes", the scanner will read the infrared channel,
thus allowing defect removal in software. The infrared image is read
during a second scan, with no options altered. The backend must not be
restarted between the scans. If you use scanimage, perform a batch scan
with batch-count=2 to obtain the IR information.
- --depth
<n>
- Here <n> can either be 8 or the maximum number of bits supported by
the scanner (10, 12, or 14). It specifies whether or not the scanner
reduces the scanned data to 8 bits before sending it to the backend. If 8
bits are used, some information and thus image quality is lost, but the
amount of data is smaller compared to higher depths. Also, many imaging
programs and image formats cannot handle depths greater than 8 bits.
- --autofocus
- Perform autofocus operation. Unless otherwise specified by the other
options ( --focus-on-centre and friends), focusing is performed on
the centre of the selected scan area.
- --ae-wb
- --ae
- Perform a pre-scan to calculate exposure values automatically.
--ae-wb will maintain the white balance, while --ae will
adjust each channel separately.
- --exposure
- Multiply all exposure times with this value. This allows exposure
correction without modifying white balance.
- --load
- Load the next slide when using the slide loader.
- --eject
- Eject the film strip or mounted slide when using the slide loader.
- --reset
- Reset scanner. The scanner will perform the same action as when power is
turned on: it will eject the film strip and calibrate itself. Use this
whenever the scanner refuses to load a film strip properly, as a result of
which --eject does not work.
The configuration file /etc/sane.d/coolscan2.conf specifies the
device(s) that the backend will use. Owing to the nature of the supported
connection types SCSI, USB, and IEEE 1394, the default configuration file
supplied with the SANE distribution should work without being edited.
Each line in the configuration file is either of the following,
where all entries are case-sensitive:
- blank or starting with a
'#' character
- These lines are ignored, thus '#' can be used to include comments.
- containing only
the word "auto"
- This instructs the backend to probe for a scanner by scanning the buses
for devices with know identifiers. This is the action taken when no
configuration file is present.
- a line of the form
<interface>:<device>
- Here <interface> can be one of "scsi" or "usb",
and <device> is the device file of the scanner. Note that IEEE 1394
devices are handled by the SBP-2 module in the kernel and appear to SANE
as SCSI devices.
- /usr/lib/x86_64-linux-gnu/sane/libsane-coolscan2.a
- The static library implementing this backend.
- /usr/lib/x86_64-linux-gnu/sane/libsane-coolscan2.so
- The shared library implementing this backend (present on systems that
support dynamic loading).
- /etc/sane.d/coolscan2.conf
- Configuration file for this backend, read each time the backend is
initialized.
- SANE_DEBUG_COOLSCAN2
- 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.
Currently, the SANE protocol does not allow automatically updating
options whenever the hardware changes. Thus the number of choices for the
--frame option will be fixed when the backend is initialized (usually
when the user runs the frontend). In particular, if there is no film strip
in the automatic film strip feeder when the backend is initialized, the
frame option will not appear at all. Also, restarting the frontend after
swapping film adapters is strongly recommended.
Linux kernels prior to 2.4.19 had a patch that truncated INQUIRY
data from IEEE 1394 scanners to 36 bytes, discarding vital information about
the scanner. The IEEE 1394 models therefore only work with 2.4.19 or
later.
No real bugs currently known, please report any to the backend
maintainer or the SANE developers' email list.
The backend is written and maintained by András Major
(andras@users.sourceforge.net).