Seems to only work if you base64 encode the binary

use 5.010;
use strict;
use warnings;

use LWP::UserAgent;
use Tk;
use Tk::PNG;
use MIME::Base64;

my $url = 'http://www.perl.com/images/ads/tpcip_banner-1200x150.png';
my $ua = LWP::UserAgent->new(agent => '');
my $response = $ua->get($url);
die $response->status_line if not $response->is_success;
my $data = MIME::Base64::encode_base64($response->decoded_content());

my $mw = MainWindow->new;
my $photo = $mw->Photo(-data => $data, -format => 'PNG');
$mw->Label(-image => $photo)->pack();
MainLoop;
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