Recursively compress JPEG/PNG, requires mozjpeg & imagemagick

recursive_cjpeg.sh

export IFS="
"

# You may want to add patterns like "*.bmp", "*.tiff", etc
for i in $(find .	\( -iname "*.jpg"	\
			-o -iname "*.jpeg"	\
			-o -iname "*.png"	\)); do
	echo "Compressing $i"
	convert "$i" pnm:- | cjpeg > "$i.comp"
	mv "$i" "$i.trash"
	mv "$i.comp" "$i"
done

# To remove trash:
#find . -name "*.trash" -delete