In case the OP was actually wanting to use the script to return an image, not html, here's another way to do it. This script uses LWP to grab an image from another server and send it along. You can use it inside the src attribute of an image tag.

use LWP::UserAgent;
my $ua = LWP::UserAgent->new;
my $response =  $ua->get('http://www.perl.org/simages/lcamel.gif');
die "Unable to retrieve image." unless ($response->is_success);
print "Content-type: image/jpeg\n\n";
print $response->content;
[download]