An unintrusive frontend of scanimage which acts as a paper to pdf converter suitable for texts.
Table of contents
Remember that the output file supplied in the command line can either be an empty file or an existing PDF file. In the latter case, newly scanned documents will be automatically appended to the tail of the file.
Also note that the mode, resolution and source options must be supported by your scanner.
Default options are defined in the
./spectrscan.conf file which is a symlink
that points to the
Scan double sided paper using the ADF
./spectrscan -t out.pdf
Take 3 papers as an example. Each paper has 2 sides, so there are 6 total sides. Mark each side with a progressive number:
Put the papers in the ADF so that sides 1,3,5 (in this order) will be scanned. Side 1 is the one facing towards you.
Once these 3 sides are scanned you should see sides 6,4,2 (in this order) out of the ADF. Side 6 is now facing towards you. This means that the ADF reverses the order of the papers (if you have a scanner with this feature).
You can now sides 6,4,2 (in this order) in the ADF. spectrscan will sort the the sides so that the final result will be
In case your scanner does not reverse the order you can use the following option
./spectrscan --two-sided-reverse out.pdf
which is comparable to a result of
for the previous example
Scan in colour, with a resolution of 300 DPI, using the flatbed, on the output file
./spectrscan -m Color -r 300 -s Flatbed out.pdf
Enable unpaper (same procedure for imagemagick):
./spectrscan -u out.pdf ./spectrscan --unpaper_options='<unpaper options>' out.pdf
If the scanned text results unreadable try using the
Gray mode instead
of the default
By default contrast is set at a very high level. You can modify the parameters with something like
./spectrscan --imagemagick_options='-normalize -level 20%,100%,1.0'
and see what happens.
Usage: spectrscan [OPTION] OUTFILE An unintrusive frontend of scanimage which acts as a paper to pdf converter suitable for texts. If the ouput file exists then the new scanned documents will be added as the tail of the existing one. The default system scanner is used. Mandatory arguments to long options are mandatory for short options too. Options: -h, --help print this help -i, --imagemagick=OPTIONS pass options to ImageMagick to post-process the documents --list-modes list all possible scan modes --list-resolutions list all possible resolutions --list-sources list all possible sources -m, --mode=MODE scan in Color, Lineart, Gray or whatever supported method --print-flags print the enabled options. This can also be used to print the default options -r, --resolution=RESOLUTION page resolution in DPI -s, --source=SOURCE scan from the ADF, Flatbed or whatever supported method -t, --two-sided toggle preserve the order in double sided paper: scan a batch of papers one side, then the other --two-sided-reverse same as '--two-sided' but with the need of reversing every single paper. This option conflicts with '--two-sided' -u, --unpaper[=OPTIONS] enable unpaper. You may pass options to unpaper Exit status: 0 if OK, 1 if an error occurred. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>. Copyright © 2017 Franco Masotti.
Parallel image processing (based on the number of processor cores) cuts the time by a factor of
#coresafter page scanning has taken place. This is very effective for a large number of pages.
Two-sided page scanning.
Basic unpaper and ImageMagick post-processing.
Relevant links and ideas
Dependencies and explanations
- Scipting language interpreter
- Basic software like
- Basic software like
- Filter some output from miscellaneous commands
- Scanner software
- TIFF to PDF converter and image processing tool
- Remove issues with scanned images (paper margins, etc...)
- Execute image post processing jobs in parallel
Fix the newly scanned immages by truncating the unnecessary parts. This is mostly useful when scanning from the ADF
In my case I have an HP Officejet 2620 connected via USB to a server as a network printer/scanner. Scanning using the "Flatbed" option poses no problems, while using the "ADF", the image is somehow corrupted and it contains a black box adjacent to the scanned document. If I try to post process the image with unpaper and/or ImageMagick serveral errors are reported. The only solution I found was to use
pamfix -truncate. I still haven't determined the cause of this problem
A "libre" version of the package is available in Parabola GNU/Linux-libre, described like this:
A toolkit for manipulation of graphic images, without nonfree parts and patent issues
- show preview
- number of pages to scan
- option for prompting for each page to scan
- better default options to pass to unpaper
- OCR (training (GOCR)? + text file outputs)
- options: keep PDF, keep txt, keep both
- better processing
- watch inotifies for a new out*.tiff would be faster than post-processing in parallel
Origin of the name
The name comes from spectrwm
If pdftk repots that PDF files are missing this is probably due to the
new ImageMagick security policies. Remove
This is the error returned by
convert: attempt to perform an operation not allowed by the security policy `PDF' @ error/constitute.c/IsCoderAuthorized/408.
Copyright (C) 2017-2018 frnmst (Franco Masotti)
spectrscan is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.