#!/bin/sh

if [ -z "$1" ]; then
echo "Usage: optimize-image.sh filename"
exit 1;
fi

if [ ! -f "$1" ]; then
echo "$1 is not a file"
exit 1;
fi

OLD=`stat -c %s "$1"`
jpegtran -copy none -optimize -perfect -progressive -outfile "$1.tmp" "$1"
jpegtran -copy none -optimize -perfect -outfile "$1.tmq" "$1"
if [ -f "$1.tmp" -a -f "$1.tmq" ]; then
    S_PROG=`stat -c %s "$1.tmp"`
    S_NORM=`stat -c %s "$1.tmq"`
    if [ $S_PROG -ge $S_NORM ]; then
   mv -f "$1.tmq" "$1"
   rm -f "$1.tmp"
    else
   mv -f "$1.tmp" "$1"
   rm -f "$1.tmq"
    fi;
fi

NEW=`stat -c %s "$1"`
echo "$1, old size: $OLD, new size: $NEW"