#!/usr/bin/perl

use strict;
use warnings;
use MIME::Base64;
use Imager;
use Tk;
use Tk::PNG;

# load image:
my $img = Imager->new(file => 'test.png') or die Imager->errstr;

# tk window:
my $mw = tkinit(-title => 'Imager & Tk::Photo');

my $img_lab = $mw->Label(
    -image => my $photo = $mw->Photo,
)->pack(
    -fill => 'both',
    -expand => 1,
);

# react on resize:
$img_lab->bind(
    '<Configure>' => sub {
        my $new_img = $img->scale(
            xpixels => $img_lab->width,
            ypixels => $img_lab->height,
            type    => 'nonprop',
        );
        
        $new_img->write(
            data => \my $data,
            type => 'png',
        ) or die $new_img->errstr;
        
        $photo->configure(data => encode_base64($data));
    },
);

$mw->geometry("=200x200");

MainLoop;