scan2image.sh

#!/bin/bash
# scan2image.sh: Scan Key Daemon scan-to-image script example
# Copyright (C) 2016 Frank Abelbeck <frank.abelbeck@googlemail.com>
#
# This file is part of the brscankeyd program "brscankeyd.py".
#
# This program 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.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>."""

#
# usage: scan2image.sh devicename [resolution]
#
if [ $# -eq 0 ]; then
	cat <<ENDOFMSG
Need at least one argument (SANE device address)!
usage: scan2image.sh SANEADDRESS [RESOLUTION]
       RESOLUTON defaults to 600 (dpi).
ENDOFMSG
	exit 1
fi

if [ ! -e "/usr/bin/scanimage" ]; then
	echo "Could not find scanimage (part of sane-backends)!"
	exit 1
fi

if [ ! -e "/usr/bin/convert" ]; then
	echo "Could not find convert (part of imagemagick)!"
	exit 1
fi

#
# create unique filename from date and if necessary from an index
#
# target directory for scans (created automatically if it does not exist):
#  - if SCANDIR is set in the environment (e.g. from "scan dir" in the .ini, or
#    exported manually), that wins;
#  - otherwise default to a "Scans" folder inside the user's XDG Pictures dir
#    (localised, e.g. ~/Afbeeldingen on a Dutch system), falling back to
#    ~/Pictures if the xdg-user-dir helper is unavailable.
if [ -z "$SCANDIR" ]; then
	if command -v xdg-user-dir >/dev/null 2>&1; then
		SCANDIR="$(xdg-user-dir PICTURES)/Scans"
	else
		SCANDIR="$HOME/Pictures/Scans"
	fi
fi
/bin/mkdir -p "$SCANDIR"

DATE="$(/bin/date +%Y-%m-%d)"
FILENAME="$SCANDIR/"$DATE"_scan.jpg"
N=-1
while [ -e "$FILENAME" ]; do
	# filename already exists: increment counter, try again
	let "N++"
	FILENAME="$SCANDIR/"$DATE"_scan_$N.jpg"
done

if [ -n "$2" ]; then
	RESOLUTION="$2"
else
	RESOLUTION=300
fi

# perform the scan
#  (1) scan the flatbed to a temporary image (scanimage emits PNM on stdout;
#      status messages go to stderr and are captured in the daemon's log)
#  (2) convert that image to a JPG at the target location
#  (3) remove the temporary image
TMPIMG="$(/usr/bin/mktemp -u).pnm"
/usr/bin/scanimage --device-name="$1" --mode="24bit Color[Fast]" --resolution="$RESOLUTION" --source="FlatBed" >"$TMPIMG"
/usr/bin/convert "$TMPIMG" -quality 92 "$FILENAME"
/bin/rm -f "$TMPIMG"