sane-canon - SANE backend for Canon flatbed scanners
DESCRIPTION
The sane-canon library implements a SANE (Scanner Access
Now Easy) backend that provides access to the following
Canon flatbed scanners:
CanoScan 300
CanoScan 600
CanoScan 2700F
No parallel port and USB scanners are supported and there
are no plans to support them in the future.
IMPORTANT: this is alpha code. Don't expect this to work
correctly. Many functions are missing, others contain
errors. In some cases, your computer might even hang. It
cannot be excluded (although I consider it extremely
unprobable) that your scanner will be damaged.
That said, TESTERS ARE WELCOME. Send your bug reports and
comments to Manuel Panea <mpd@rzg.mpg.de>.
DEVICE NAMES
This backend expects device names of the form:
special
Where special is the path-name for the special device that
corresponds to a SCSI scanner. The special device name
must be a generic SCSI device or a symlink to such a
device. The program sane-find-scanner helps to find out
the correct device. Under Linux, such a device name could
be /dev/sga or /dev/sge, for example. See sane-scsi(5)
for details.
CONFIGURATION
The contents of the canon.conf file is a list of device
names that correspond to Canon scanners. Empty lines and
lines starting with a hash mark (#) are ignored. Only one
device name can be listed in canon.conf.
TIPS
When scanning either slides or negatives, I found that I
must set the gamma value to something about 2.2 to 2.4 (I
set the same value for all three red, green, blue). Also,
for slides, using "Auto Exposure" helps a lot.
The "Auto Exposure" function for slides makes the scanner
do a first pass on the film to determine the Highlight and
yet another pass to determine the focus value. After that,
the real scanning pass takes place. The "Auto Exposure"
function is not available for negatives yet.
Even after "Auto Focus", the image I get is often a bit
too blurred. I found that using the GIMP to do a "Fil
ter->Enhance->Sharpen" at about 40 to 60 improves the
image quite a bit. In fact, I find it so good that I might
implement a sharpen filter into the backend in the future.
The "native" scanner resolutions of the 2700F are the
integer sub-multiples of 2720 dpi, i.e. 1360, 680, 340 and
170. You can scan at any other resolution, but you will
notice that the image has noticeably more jaggies that
when using one of the "native" resolutions.
FILES
/etc/sane.d/canon.conf
The backend configuration file (see also descrip
tion of SANE_CONFIG_DIR below).
/usr/lib/sane/libsane-canon.a
The static library implementing this backend.
/usr/lib/sane/libsane-canon.so
The shared library implementing this backend (pre
sent on systems that support dynamic loading).
ENVIRONMENT
SANE_CONFIG_DIR
This environment variable specifies the list of
directories that may contain the configuration
file. Under UNIX, the directories are separated by
a colon (`:'), under OS/2, they are separated by a
semi-colon (`;'). If this variable is not set, the
configuration file is searched in two default
directories: first, the current working directory
(".") and then in /etc/sane.d. If the value of the
environment variable ends with the directory sepa
rator character, then the default directories are
searched after the explicitly specified directo
ries. For example, setting SANE_CONFIG_DIR to
"/tmp/config:" would result in directories
"tmp/config", ".", and "/etc/sane.d" being searched
(in this order).
SANE_DEBUG_CANON
If the library was compiled with debug support
enabled, this environment variable controls the
debug level for this backend. Higher debug levels
increase the verbosity of the output.
SEE ALSO
sane(7), sane-scsi(5), sane-find-scanner(1)
http://www.rzg.mpg.de/~mpd/sane/
/usr/doc/sane-1.0.5/canon/canon.install2700F.txt (instal
lation of a CanoScan 2700F)
AUTHOR
Helmut Koeberle, Manuel Panea, and Markus Mertinat
Man page by Henning Meier-Geinitz (mostly based on
canon.README)
Man(1) output converted with
man2html