sane-apple(5) SANE Scanner Access Now Easy sane-apple(5)NAMEsane-apple - SANE backend for Apple flatbed scanners
DESCRIPTION
The sane-apple library implements a SANE (Scanner Access
Now Easy) backend that provides access to Apple flatbed
scanners. At present, the following scanners are supported
from this backend:
--------------- ----- ------------------ ------
AppleScanner 4bit 16 Shades of Gray
OneScanner 8bit 256 Shades of Gray
ColorOneScanner 24bit RGB color 3-pass
If you own a Apple scanner other than the ones listed
above that works with this backend, please let us know by
sending the scanner's model name, SCSI id, and firmware
revision to sane-devel@mostang.com. See
http://www.mostang.com/sane/mail.html for details on how
to subscribe to sane-devel.
DEVICE NAMES
This backend expects device names of the form:
special
Where special is either the path-name for the special
device that corresponds to a SCSI scanner. For SCSI scan-
ners, the special device name must be a generic SCSI
device or a symlink to such a 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 apple.conf file is a list of options
and device names that correspond to Apple scanners. Empty
lines and lines starting with a hash mark (#) are ignored.
See sane-scsi(5) on details of what constitutes a valid
device name.
Options come in two flavors: global and positional ones.
Global options apply to all devices managed by the backend
whereas positional options apply just to the most recently
mentioned device. Note that this means that the order in
which the options appear matters!
SCSI ADAPTER TIPS
SCSI scanners are typically delivered with an ISA SCSI
adapter. Unfortunately, that adapter is not worth much
since it is not interrupt driven. It is (sometimes) pos-
sible to get the supplied card to work, but without inter-
rupt line, scanning will put so much load on the system,
that it becomes almost unusable for other tasks.
FILES
/usr/freeware/etc/sane.d/apple.conf
The backend configuration file (see also descrip-
tion of SANE_CONFIG_DIR below).
/usr/freeware/lib32/sane/libsane-apple.a
The static library implementing this backend.
/usr/freeware/lib32/sane/libsane-apple.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 /usr/freeware/etc/sane.d. If the
value of the environment variable ends with the
directory separator character, then the default
directories are searched after the explicitly spec-
ified directories. For example, setting SANE_CON-
FIG_DIR to "/tmp/config:" would result in directo-
ries "tmp/config", ".", and "/usr/free-
ware/etc/sane.d" being searched (in this order).
SANE_DEBUG_APPLE
If the library was compiled with debug support
enabled, this environment variable controls the
debug level for this backend. E.g., a value of 255
requests all debug output to be printed. Smaller
levels reduce verbosity.
CURRENT STATUS
The apple backend is now in version 0.3 (Tue Jul 21 1998).
Since I only have the AppleScanner and not the other mod-
els (OneScanner, ColorOneScanner) I can only develop/test
for the AppleScanner effectively. However with this
release I almost complete the gui part of all scanners.
Most of the functionality is there. At least OneScanner
should scan at the AppleScanner's compatible modes (Lin-
eArt, HalfTone, Gray16). My personal belief is that with a
slight touch of debugging the OneScanner could be actually
usable. The ColorOneScanner needs more work. AppleScanner
is of course almost fully supported.
MISSING FUNCTIONALITY
Currently all 3 models are lacking upload/dowload support.
AppleScanner
Cannot up/download a halftone pattern.
OneScanner
Cannot up/download halftone pattern and calibration
vector.
ColorOneScanner
Cannot up/download halftone pattern, calibration
vectors, custom Color Correction Table (CCT) and of
course custom gamma tables.
Park/UnPark (OneScanner, ColorOneScanner)
The above functionalities are not only missing because I
don't actually have the hardware to experiment on it.
Another reason is the lack of understanding of how SANE
API could provide enaugh means to me to actually describe
other array types than the gamma one.
UNSUPPORTED FEATURES.
The following "features" will never be supported. At least
as I am maintaining the sane-apple backend.
NoHome (AppleScanner)
The scanner lamp stays on and the carriage assembly
remains where it stops at the end of the scan.
After two minutes, if the scanner does not receive
another SCAN command the lamp goes off and the car-
riage returns to the home position.
Compression (AppleScanner)
The Scanner can compress data with CCITT Group III,
one dimensional algorithm (fax), and the Skip White
Line algorithm.
Multiple Windows (AppleScanner)
AppleScanner may support multiple windows. It would
be a cool feature and a challenge for me to code it
if you could intermix different options for differ-
ent windows (scan areas). This way you could scan a
document in LineArt mode but the figures in it on
Gray and in a different resolution. Unfortunately
this is impossible.
Scan Direction (OneScanner)
It controls the scan direction. (?)
Status/Reset Button (OneScanner)
This option controls the status of the button in
OneScanner model. You can also reset the button
status by software.
BUGS
The bugs in a sane backend are divided in two classes. We
have GUI bugs and scanner specific bugs.
We know we have a GUI bug when a parameter is not showing
up itself when it should (active) or vice versa. To find
out which parameters are active accross various Apple
modes and models from the documentation
ftp://ftpdev.info.apple.com/devworld/Technical_Documenta-
tion/Peripherals_Documentation/ is an interesting exer-
cise. I may missed some dependancies. For example for the
threshold parameter the Apple Scanners Programming guide
says nothing. I had to assume that is valid only in Lin-
eArt mode.
Scanner specific bugs are mostly due to mandatory round
offs in order to scan. In the documentation in some place
states that the width of the scan area should be a byte
multiple. In an other place says that the width of the
scan area should be an even byte multiple. Go figure...
Other source of bugs are due to scsi communcation, scsi
connects and disconnects. However the classical bugs are
still there. So you may encouter buffer overruns, null
pointers, memory corruption and SANE API violations.
SIGSEGV on SliceBars
When you try to modify the scan area from the slice
bar you have a nice little cute core dump. I don't
know why. If you select the scan are from the pre-
view window, or by hand typing the numbers every-
thing is fine. The SIGSEGV happens deep in gtk
library (gdk). I really cannot debug it.
Options too much
It is possible, especially for the ColorOneScanner,
that the backend's options panel to exceed from
your screen. It happens with mine and I am running
at 1024x768 my X Server. What can I say? Try
smaller fonts in the X server, or virtual screens.
Weird SCSI behaviour.
I am quoting David Myers Here...
>> OS: FreeBSD 2.2.6
>> CC: egcs-1.02
>Just wanted to follow up on this... I recently
changed my SCSI card from
>the Adaptec 2940UW to a dual-channel Symbios 786
chipset. When I started up
>SANE with your driver, I managed to scan line art
drawings okay, but Gray16
>scans led to a stream of SCSI error messages on
the console, ultimately
>hanging with a message saying the scanner wasn't
releasing the SCSI bus.
>This may be that the Symbios is simply less toler-
ant of ancient
>hardware, or may be bugs in your driver or in SANE
itself...
DEBUG
If you encounter a GUI bug please set the environment
variable SANE_DEBUG_APPLE to 255 and rerun the excact
sequence of keystrokes and menu selections to reproduce
it. Then send me a report with the log attached.
It would be very helpfull if you have handy an Apple
machine (I am not sure how Mackintoshs are spelled) with
the AppleScanners driver installed and check what option
are grayed out (inactive) in what modes and report back to
me.
If you want to offer some help but you don't have a scan-
ner or you don't have the model you would like to offer
some help, or you are a sane developer and you just want
to take a look at how the apple backend looks like. Goto
to apple.h and #define the NEUTRALIZE_BACKEND macro. You
can select the scanner model through the
APPLE_MODEL_SELECT macro. Available options are APPLESCAN-
NER, ONESCANNER, COLORONESCANNER.
If you encounter a SCSI bus error or trimmed and/or dis-
placed images please also set the environment variable
SANE_DEBUG_SANEI_SCSI to 255 before sendme the report.
TODO
Non Blocking Support
Make sane-apple a non blocking backend. Properly
support for sane_set_io_mode and sane_get_select_fd
Scan Make scan possible for all models in all supported
modes.
Missing Functionality.
SEE ALSOsane(7), sane-scsi(5)AUTHOR
The sane-apple backend was written not entirely from
scratch by Milon Firikis. It is mostly based on the mustek
backend from David Mosberger and Andreas Czechanowski
sane-backends 1.0.12 13 May 1998 sane-apple(5)
