optimize.sh

#!/bin/sh
 
# script for optimizing images in a directory (recursive)
# pngcrush & jpegtran settings from:
# http://developer.yahoo.com/performance/rules.html#opt_images

# pngcrush
find . -iname "*.png" | while read png
do
    echo "crushing $png ..."
    pngcrush -rem alla -reduce "$png" temp.png
 
    # preserve original on error
    if [ $? = 0 ]; then
        mv -f temp.png "$png"
    else
        rm temp.png
    fi
done
 
# jpegtran
find . -iname "*.jpg" | while read jpg
do
    echo "crushing $jpg ..."
    jpegtran -copy none -optimize -perfect "$jpg" > temp.jpg
 
    # preserve original on error
    if [ $? = 0 ]; then
        mv -f temp.jpg "$jpg"
    else
        rm temp.jpg
    fi
done