ImageMagick convert scan

Compress, using quality

#!/bin/bash
mkdir new
for file in *.jpg
do
 nameext="${file##*/}"
 name="${nameext%.*}"
 ext="${nameext##*.}"
 tofile="./new/${name}.${ext}"
 echo "${file} --> ${tofile}"
 convert "${file}" -white-threshold 92% -resize 1500x -quality 80 "${tofile}"
done
echo "Press ENTER to continue .."
read

Text document resize and quality

After scanning a document you may want to resize and compress the resulting image. You should scan with a higher resolution so you can have a better-quality lower resolution.

convert "${file}" -resize 1500x -quality 85 "${tofile}"

Text document white threshold

The white paper background will probably not end up being white so we add a 'white-threshold'. A lower value will mean more light areas are converted to pure white.

convert "${file}" -white-threshold 85% -resize 1500x -quality 80 "${tofile}"

Split up picture

When you scan all your old photos, four at a time, you can use this to divide them up in quarters.

convert "${file}" -crop 2x2+4+4@ +repage +adjoin "${tofile}"

Also see

• ImageMagick tools