use CGI;
my $img = CGI->new->param('name');
my ($type) = (lc($img) =~ m/([^\.]+)$/s);
my %switch = qw/jpg jpeg tif tiff/;
$type = $switch{$type} if exists $switch{$type};
print "Content-type: image/$type\n\n";
open(IMG,"</path/to/files/$img");
binmode(IMG); binmode(STDOUT);
print while <IMG>;
close(IMG);
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My two cents,
  -Adam