#!/usr/bin/perl -w  
use threads;
use Thread::Queue;
use Tk;
use strict;

my $cmdq = Thread::Queue->new();
my $respq = Thread::Queue->new();

my $thrd = threads->create(\&image_loader);

my $mw = MainWindow->new;

# ...the usual widget building here...

my $repeat_id = $mw->repeat($interval, \&image_handler);

$cmdq->enqueue('GO');

MainLoop;


sub image_handler { 
	return unless $respq->pending;
	
	my $buffer = $respq->dequeue();
	...load into your frame here...
	$cmdq->enqueue('GO');
}
#
#	assumes your image loader persists
#
sub image_loader {
	while (1) {
		my $go = $cmdq->dequeue();
		last 
			if ($go eq 'STOP');
		...do your image loading business here...
		$respq->enqueue($imagebuffers);
	}
}