m. allan noah ha scritto:
>> I've tried scanning at the lowest res supported by the device with scanimage
>> (75dpi). Opening the .pnm file produced with Gimp I noticed that the
>> dimensions are exactly the ones of an A4, BUT resolution of the image is
>> 72dpi not 75!
>>
>
> that is only because the pnm format does NOT store the resolution, and
> gimp defaults to 72.
>
> So scaling it back to 75 I get the actual scanned portion
>
>> dimensions which is about 265mm x 205mm.
>> The problem shows up already in the preview "pre-scan" so at the lowest res.
>>
>
> I dont want the physical dimensions, just the pixel size. Does
> reducing the -y parameter reduce the height?
>
> can you send us the output of scanimage --help
>
> allan
>
The actual size in pixels is 624 x 840.
Setting the -y actually reduces the height but to a wrong extent AFAIK:
I've tried with "-y 100" but I obtained a 224 pixel high image.
Finally scanimage --help produces this output:
Usage: scanimage [OPTION]...
Start image acquisition on a scanner device and write PNM 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), and %i (index number)
-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 number in filename by an amount of #
--batch-double increment page number by two for 2sided originals
being scanned in a single sided scanner
--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 default input buffersize
-V, --version print version information
Options specific to device `hpljm1005:libusb:003:032':
--resolution 75|100|150|200|300|600|1200dpi [75]
resolution
-l 0..220mm [0]
tl-x
-t 0..330mm [0]
tl-y
-x 0..220mm [220]
Width of scan-area.
-y 0..330mm [330]
Height of scan-area.
--brightness 1..11 [6]
Set the brightness
--contrast 1..11 [6]
Set the contrast
--mode Gray|Color [Color]
Selects the scan mode (e.g., lineart, monochrome, or color).
Type ``scanimage --help -d DEVICE'' to get list of all options for DEVICE.
List of available devices:
hpljm1005:libusb:003:032
Thanks for your help
