Are you trying to open raw files directly? If so, I’d run through ART-cli first. Something like this:
#!/bin/bash
if [ "$1" = "--fast" ]; then
fast=-f
shift
fi
d=$(mktemp -d)
t=$d/p1.arp
cat <<EOF > $t
[Version]
Version=1015
[Color Management]
OutputProfile=(none)
EOF
ART-cli --progress $fast -s -p $t -Y -t -b32 -c "$@" 2>"$d/error" \
| zenity --width=500 --progress --auto-close --text="Converting to TIFF..."
if [ $? -ne 0 ]; then
exit 0
fi
err=
if [ -f "$d/error" ]; then
err=$(cat "$d/error")
fi
rm -rf $d
if [ "$err" != "" ]; then
zenity --error --text="$err"
else
i=0
for fn in "$@"; do
tiffs[$i]="${fn%.*}.tif"
i=$(expr $i + 1)
done
./gimp-open-layers.sh "${tiffs[@]}" || zenity --error --text="Something went wrong..."
fi
Note that this assumes that you have called the previous script gimp-open-layers.sh, and that it is in the same directory as the one above, which you can call e.g. gimp-open-layers-raw.sh.
Then, here’s the related user command:
[ART UserCommand]
Label=Open as layers in GIMP
Command=./gimp-open-layers-raw.sh
FileType=raw