SANE Scanner Access Now Easy sane-test(5)
NAME
sane-test - SANE backend for testing frontends
DESCRIPTION
The sane-test library implements a SANE (Scanner Access Now
Easy) backend that allows testing the SANE installation and SANE frontends. It provides access to a (nearly) unlimited number of virtual devices. There is no support for realscanners or cameras. However, the backend simulates scan-
ning and setting options. The idea is not only to find bugs in frontends but also toshow all capabilities of SANE. Therefore sane-test imple-
ments functions and options that are not (or seldom) found in other backends. The backend is commented out in /etc/sane.d/dll.conf, so either the comment character must be removed or the backendmust be called explicitly. E.g. `scanimage -d test' or
`xscanimage test'. SCAN MODE OPTIONS Option mode selects the scan mode (Gray or Color). Option depth determines the number of bits per sample (1. 8, or 16). Keep in mind, that this value refers to the sample, not the pixel. So depth=16 results in 48 bits per pixel in color mode. The most usual combinations are mode=Gray, depth=1 for lineart, mode=Gray, depth=8 for gray and mode=Color, depth=8 for color mode. The combination ofcolor and 1-bit mode is quite obscure (8 colors) but allowed
in the SANE standard. However, the meaning of bits is not defined. Currently 1 = high intensity and 0 = low intensity is used.Setting option hand-scanner results in the test-backend
behaving like a hand-scanner. Hand-scanners do not know the
image height a priori. Instead, they return a height of -1.
Setting this option allows to test whether a frontend can handle this correctly. This option also enables a fixed width of 11 cm.Setting option three-pass simulates a three-pass scanner.
Older color scanners needed to scan the image once per color (reg/green/blue) to get the full image. Therefore, in this mode three single frames are transmitted in color mode.Option three-pass-order provides support for changing the
order of the three frames (see option three-pass above). A
frontend should support all orders.sane-backends 1.0.19 Last change: 2 Jan 2006 1
SANE Scanner Access Now Easy sane-test(5)
Option resolution sets the resolution of the image in dots per inch. Option source can be used to simulate an Automatic Document Feeder (ADF). After 10 scans, the ADF will be "empty". SPECIAL OPTIONSOption test-picture allows to set the image that's returned
to the frontend. While "Solid white" and "Solid black" are quite obvious, the other options need some more explanation. Color patterns are used to determine if all modes and their colors are represented correctly by the frontend. The grid should look like the same in every mode and resolution. A table of all the test pictures can be found at:http://www.meier-geinitz.de/sane/test-backend/test-
pictures.html.If option invert-endianess is set, the upper and lower bytes
of image data in 16 bit modes are exchanged. This option can be used to test the 16 bit modes of frontends, e.g. if the frontend uses the correct endianess.If option read-limit is set, the maximum amount of data
transferred with each call to sane_read() is limited.
Option read-limit-size sets the limit for option read-limit.
A low limit slows down scanning. It can be used to detect errors in frontend that occur because of wrong assumptions on the size of the buffer or timing problems.Option read-delay enables delaying data to the frontend.
Option read-delay-duration selects the number of
microseconds the backends waits after each transfer of abuffer. This option is useful to find timing-related bugs,
especially if used over the network.If option read-return-value is different from "Default", the
selected status will be returned by every call tosane_read(). This is useful to test the frontend's handling
of the SANE statii.If option ppl-loss is different from 0, it determines the
number of pixels that are "lost" at the end of each line. That means, lines are padded with unused data.Option fuzzy-parameters selects that fuzzy (inexact) parame-
ters are returned as long as the scan hasn't been started. This option can be used to test if the frontend uses the parameters it got before the start of the scan (which it shouldn't).sane-backends 1.0.19 Last change: 2 Jan 2006 2
SANE Scanner Access Now Easy sane-test(5)
Option non-blocking determines if non-blocking IO for
sane_read() should be used if supported by the frontend.
If option select-fd is set, the backend offers a select
filedescriptor for detecting if sane_read() will return
data.If option enable-test-options is set, a fairly big list of
options for testing the various SANE option types is enabled.Option print-options can be used to print a list of all
options to standard error. GEOMETRY OPTIONSOption tl-x determines the top-left x position of the scan
area.Option tl-y determines the top-left y position of the scan
area.Option br-x determines the bottom-right x position of the
scan area.Option br-y determines the bottom-right y position of the
scan area. BOOL TEST OPTIONSThere are 6 bool test options in total. Each option is num-
bered. (3/6) means: this is option 3 of 6. The numbering scheme is intended for easier detection of options not displayed by the frontend (because of missing support or bugs).Option bool-soft-select-soft-detect (1/6) is a bool test
option that has soft select and soft detect (and advanced) capabilities. That's just a normal bool option.Option bool-hard-select-soft-detect (2/6) is a bool test
option that has hard select and soft detect (and advanced) capabilities. That means the option can't be set by the frontend but by the user (e.g. by pressing a button at the device).Option bool-hard-select (3/6) is a bool test option that has
hard select (and advanced) capabilities. That means the option can't be set by the frontend but by the user (e.g. by pressing a button at the device) and can't be read by the frontend.Option bool-soft-detect (4/6) is a bool test option that has
soft detect (and advanced) capabilities. That means thesane-backends 1.0.19 Last change: 2 Jan 2006 3
SANE Scanner Access Now Easy sane-test(5)
option is read-only.
Option bool-soft-select-soft-detect-emulated (5/6) is a Bool
test option that has soft select, soft detect, and emulated (and advanced) capabilities.Option bool-soft-select-soft-detect-auto (6/6) is a Bool
test option that has soft select, soft detect, and automatic(and advanced) capabilities. This option can be automati-
cally set by the backend. INT TEST OPTIONS There are 6 int test options in total. Option int (1/6) is an int test option with no unit and no constraint set.Option int-constraint-range (2/6) is an int test option with
unit pixel and constraint range set. Minimum is 4, maximum 192, and quant is 2.Option int-constraint-word-list (3/6) is an int test option
with unit bits and constraint word list set.Option int-constraint-array (4/6) is an int test option with
unit mm and using an array without constraints.Option int-constraint-array-constraint-range (5/6) is an int
test option with unit mm and using an array with a range constraint. Minimum is 4, maximum 192, and quant is 2.Option int-constraint-array-constraint-word-list (6/6) is an
int test option with unit percent and using an array a word list constraint. FIXED TEST OPTIONS There are 3 fixed test options in total. Option fixed (1/3) is a fixed test option with no unit and no constraint set.Option fixed-constraint-range (2/3) is a fixed test option
with unit microsecond and constraint range set. Minimum is-42.17, maximum 32767.9999, and quant is 2.0.
Option fixed-constraint-word-list (3/3) is a Fixed test
option with no unit and constraint word list set. STRING TEST OPTIONS There are 3 string test options in total.sane-backends 1.0.19 Last change: 2 Jan 2006 4
SANE Scanner Access Now Easy sane-test(5)
Option string (1/3) is a string test option without con-
straint.Option string-constraint-string-list (2/3) is a string test
option with string list constraint.Option string-constraint-long-string-list (3/3) is a string
test option with string list constraint. Contains some more entries... BUTTON TEST OPTION Option button (1/1) is a Button test option. Prints some text... FILES /etc/sane.d/test.conf The backend configuration file (see also description ofSANE_CONFIG_DIR below). The initial values of most of
the basic SANE options can be configured in this file.A template containing all the default values is pro-
vided together with this backend. One of the moreinteresting values may be number_of_devices. It can be
used to check the frontend's ability to show a longlist of devices. The config values concerning resolu-
tion and geometry can be useful to test the handling of big file sizes./usr/lib/sane/libsane-test.a
The static library implementing this backend./usr/lib/sane/libsane-test.so
The shared library implementing this backend (present on systems that support dynamic loading). ENVIRONMENTSANE_CONFIG_DIR
This environment variable specifies the list of direc-
tories 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 thedirectory separator character, then the default direc-
tories are searched after the explicitly specifieddirectories. 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-backends 1.0.19 Last change: 2 Jan 2006 5
SANE Scanner Access Now Easy sane-test(5)
SANE_DEBUG_TEST
If the library was compiled with debug support enabled, this environment variable controls the debug level forthis backend. Higher debug levels increase the verbos-
ity of the output.Example: export SANE_DEBUG_TEST=4
SEE ALSO
sane(7), http://www.meier-geinitz.de/sane/test-backend/
AUTHORHenning Meier-Geinitz
BUGS
- config file values aren't tested for correctness
ATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:_________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|____________________|____________________________________|_
| Availability | image/scanner/xsane/sane-backends|
|____________________|____________________________________|_
| Interface Stability| Uncommitted ||____________________|___________________________________|
NOTES Source for SANE is available on http://opensolaris.org.sane-backends 1.0.19 Last change: 2 Jan 2006 6