Convert JPG product images to PNG, replacing white background with transparent one.

product_clean.sh

#!/bin/bash

# Cleanup product images
# 
# This will convert images from JPG to PNG and replace the white
# background with transparent one.
# 
# This is almost verbatim copy of the script from:
# http://tech.natemurray.com/2007/12/convert-white-to-transparent.html

SRC_FOLDER=orig
SRC_EXT=jpg
DST_FOLDER=result
DST_EXT=png

# This is where all the conversion happens
function removeBackground {
	SRC=$1
	DST=$2

	# Fuzzy percentage level for white colort
	FUZZ=1

	# start real
	convert "$SRC" \( +clone -fx 'p{0,0}' \)  -compose Difference  -composite   -modulate 100,0  +matte  difference.png
	# remove the black, replace with transparency
	convert difference.png -bordercolor white -border 1x1 -matte -fill none -fuzz ${FUZZ}% -draw 'matte 1,1 floodfill' -shave 1x1 removed_black.png
	# create the matte 
	convert removed_black.png -channel matte -separate  +matte matte.png
	# negate the colors
	#convert matte.png -negate -blur 0x1 matte-negated.png
	convert matte.png -blur 0x1 matte-negated.png
	# you are going for: white interior, black exterior
	composite -compose CopyOpacity matte-negated.png "$SRC" "$DST"
	# cleanup
	rm -f difference.png removed_black.png matte.png matte-negated.png
}

for FILE in ${SRC_FOLDER}/*.${SRC_EXT}
do
	echo Converting $FILE
	NEWFILE="${DST_FOLDER}"/$(basename "$FILE" .${SRC_EXT}).${DST_EXT}
	removeBackground "$FILE" "$NEWFILE"
done