ImageMagick convert scan

Compress, using quality

mkdir new
for file in *.jpg
do
 nameext="${file##*/}"
 name="${nameext%.*}"
 ext="${nameext##*.}"
 convert "${file}" -quality 85 "./new/${name}.${ext}"
done

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 '*.jpg' -set filename:f '%t(resized).%e' -resize 1500x -quality 85 '%[filename:f]'

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 "image.jpg" -white-threshold 92% -resize 1500x -quality 80 "(new)image.jpg"

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 "image.jpg" -white-threshold 92% -resize 1500x -quality 80 "(new)image.jpg"

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 "image.jpg" -crop 2x2+4+4@ +repage +adjoin "(new)image.jpg"

Also see

• ImageMagick tools