use strict;
use warnings;
use Image::Magick;
use File::Spec::Functions qw(splitpath);

my $thumbX = 100;
my $thumbY = 66;

my $filename = shift;
my $image = Image::Magick->new ();
$image->ReadImage ($filename);

my ($height, $width) = $image->Get ('height', 'width');
my ($x, $y) = $height < $width ? ($thumbX, $thumbY) : ($thumbY, $thumbX);
my ($drive, $dir, $file) = splitpath ($filename);
$file =~ s/(\..*?)$/_s$1/;

$image->Thumbnail (width=>$x, height=>$y);
$image->Write ("$drive${dir}$file");