#!/usr/bin/perl
# Author: Peter R. Wood, http://prwdot.org/

use strict;

use Image::Magick;
my $quality      = "80";
my $bytes_before = 0;
my $bytes_after  = 0;

while (<>) {
    chomp;
    my $filename = $_;
    my $image    = Image::Magick->new;
    my $result   = "";
    my @pre_stat = stat($filename);
    $bytes_before += $pre_stat[7];
    $result = $image->read( filename => "$filename" );
    warn "$result" if $result;
    $result = $image->Set( quality => $quality );
    warn "$result" if $result;
    $result = $image->write( filename => "$filename" );
    warn "$result" if $result;
    my @post_stat = stat($filename);
    $bytes_after += $post_stat[7];
}

my $bytes_saved = $bytes_before - $bytes_after;
my $percent_saved = 100 * ( $bytes_saved / $bytes_before );
print "Before: $bytes_before b\n";
print "After: $bytes_after b\n";
print "Saved: $bytes_saved b\n";
print "Saved: $percent_saved %\n";