[sane-devel] Canon CanoScan LiDE 100

[Mauro Torrez]

Hi people,

in my wokplace they have acquired a new Canon CanoScan LiDE 100 scanner,
it works perfectly using the Genesys backend, but there are a few
glitches I'd like to ask you about:


First, the default color gamma, brightness, contrast is too dark. This
is not a problem if using XSane, as it lets you adjust them, but when
using e.g. Simple Scan, which doesn't let you adjust those values by
hand, the result is not good. Skanlite also has trouble correcting
color.

So my first question is: is there a way to set the default
gamma/brightness/contrast so that they're corrected when scanning from
any program? (setting them on the backend, or something like that)

I know it's Simple Scan's fault, but users prefer it to using XSane,
especially for generating multi-page PDFs.


Second, the scanner buttons. The output of scanimage --help is the
following:

Usage: scanimage [OPTION]...

Start image acquisition on a scanner device and write image data to
standard output.

Parameters are separated by a blank from single-character options (e.g.
-d epson) and by a "=" from multi-character options (e.g.
--device-name=epson).
-d, --device-name=DEVICE   use a given scanner device (e.g.
hp:/dev/scanner)
    --format=pnm|tiff      file format of output file
-i, --icc-profile=PROFILE  include this ICC profile into TIFF file
-L, --list-devices         show available scanner devices
-f, --formatted-device-list=FORMAT similar to -L, but the FORMAT of the
output
                           can be specified: %d (device name), %v
(vendor),
                           %m (model), %t (type), %i (index number), and
                           %n (newline)
-b, --batch[=FORMAT]       working in batch mode, FORMAT is `out%d.pnm'
or
                           `out%d.tif' by default depending on --format
    --batch-start=#        page number to start naming files with
    --batch-count=#        how many pages to scan in batch mode
    --batch-increment=#    increase page number in filename by #
    --batch-double         increment page number by two, same as
                           --batch-increment=2
    --batch-prompt         ask for pressing a key before scanning a page
    --accept-md5-only      only accept authorization requests using md5
-p, --progress             print progress messages
-n, --dont-scan            only set options, don't actually scan
-T, --test                 test backend thoroughly
-h, --help                 display this help message and exit
-v, --verbose              give even more status messages
-B, --buffer-size=#        change input buffer size (in kB, default 32)
-V, --version              print version information

Options specific to device `genesys:libusb:001:002':
  Scan Mode:
    --mode Color|Gray|Lineart [Gray]
        Selects the scan mode (e.g., lineart, monochrome, or color).
    --source Flatbed|Transparency Adapter [inactive]
        Selects the scan source (such as a document-feeder).
    --preview[=(yes|no)] [no]
        Request a preview-quality scan.
    --depth 8|16 [8]
        Number of bits per sample, typical values are 1 for "line-art"
and 8
        for multibit scans.
    --resolution 1200|600|400|300|200|150|100|75dpi [300]
        Sets the resolution of the scanned image.
  Geometry:
    -l 0..216.07mm [0]
        Top-left x position of scan area.
    -t 0..299mm [0]
        Top-left y position of scan area.
    -x 0..216.07mm [216.07]
        Width of scan-area.
    -y 0..299mm [299]
        Height of scan-area.
  Enhancement:
    --custom-gamma[=(yes|no)] [no]
        Determines whether a builtin or a custom gamma-table should be
used.
    --gamma-table 0..65535,... [inactive]
        Gamma-correction table.  In color mode this option equally
affects the
        red, green, and blue channels simultaneously (i.e., it is an
intensity
        gamma table).
    --red-gamma-table 0..65535,... [inactive]
        Gamma-correction table for the red band.
    --green-gamma-table 0..65535,... [inactive]
        Gamma-correction table for the green band.
    --blue-gamma-table 0..65535,... [inactive]
        Gamma-correction table for the blue band.
  Extras:
    --lamp-off-time 0..60 [15]
        The lamp will be turned off after the given time (in minutes). A
value
        of 0 means, that the lamp won't be turned off.
    --threshold 0..100% (in steps of 1) [50]
        Select minimum-brightness to get a white point
    --threshold-curve 0..127 (in steps of 1) [50]
        Dynamic threshold curve, from light to dark, normally 50-65
    --disable-interpolation[=(yes|no)] [no]
        When using high resolutions where the horizontal resolution is
smaller
        than the vertical resolution this disables horizontal
interpolation.
    --color-filter Red|Green|Blue [Green]
        When using gray or lineart this option selects the used color.
  Sensors:
    --scan[=(yes|no)] [no] [hardware]
        Scan button
    --file[=(yes|no)] [no] [hardware]
        File button
    --email[=(yes|no)] [no] [hardware]
        Email button
    --copy[=(yes|no)] [no] [hardware]
        Copy button
  Buttons:
    --clear-calibration []
        Clear calibration cache

Type ``scanimage --help -d DEVICE'' to get list of all options for
DEVICE.

List of available devices:
    genesys:libusb:001:002

As you can see, near the end there's a section "Sensors" which
enumerates the four physical buttons available on the scanner.
Executing `scanimage --scan` throws an error.
I wonder how these options are to be used, if I could write a script to
detect when the buttons are pressed, if I should use scanbuttond (which
I haven't managed to get working) or if I should simply give up as the
buttons won't work.

Thank you very much.

Regards,
Mauro Torrez.