Freeing images / unblessed reference?

[Dan Mueth <dmueth rheo uchicago edu>]

I am having difficulties freeing image resources.  I have a simple program
(included below, using Perl-Gtk-0.4) which creates images from data using
gdk_imlib_create_image_from_data and then displays them in a Gtk Pixmap. 
It does not automatically free the images and quickly uses up 30MB of RAM
after displaying 100 images.  When I use gdk_imlib_destroy_image I always
get errors: 

Can't call method "changed_image" on unblessed reference at junk.pl line 
56

What is an "unblessed reference"?  Any suggestions on how to free up these
images and avoid unblessed references would be appreciated.

Dan


---------------------------------------------------------------------
use Gtk;
use Gtk::Atoms;

init Gtk;

init Gtk::Gdk::ImlibImage;


sub do_exit {
        Gtk->exit(0);
}


sub update_image {
   for($it=0;$it<100;$it++) {
	print "Iteration: $it\n";
	if ($it % 3 eq 0) {$data="a  "x40000;}
	if ($it % 3 eq 1) {$data=" a "x40000;}
	if ($it % 3 eq 2) {$data="  a"x40000;}
	$alpha="000"x40000;
	$im3 = create_image_from_data Gtk::Gdk::ImlibImage($data,$alpha,$h,$w);
	$im3->changed_image();	

	# Render the original 24-bit Image data into a pixmap of size $w x $h 
	$im3->render($w, $h);	

	# Free up the pixmap $p3
	$p3->imlib_free;

	# Extract the image and mask pixmaps from the Image
	$p3 = $im3->move_image();
	$m3 = $im3->move_mask;

	Gtk::Gdk->flush;

	$mypixmap->set($p3,$m3);

	# Force Gtk to update before returning to main
	# For some reason, Gtk::Gdk->events_pending is always 0 even 
	#   when the window needs to be updated, so throw in an extra 
	#   Gtk->main_iteration;
	Gtk->main_iteration;
	while (Gtk::Gdk->events_pending) { Gtk->main_iteration }

	}
}


sub create_main_window {
        # Create main_window
        $main_window = new Gtk::Window('toplevel');
        $main_window->set_title("imlib_test_1");
        $main_window->set_name("main window");
        $main_window->set_uposition(20, 20);
        $main_window->signal_connect("destroy" => \&Gtk::main_quit);
        $main_window->signal_connect("delete_event" => \&Gtk::false);
        $main_window->show;

        $vbox = new Gtk::VBox(0, 0);
        $main_window->add($vbox);
        $vbox->show;


        $test_label = new Gtk::Label "  This is a test  ";
        $vbox->pack_start($test_label, 0, 0, 20);
        show $test_label;


	$w = 200;
	$h = 200;
	$data="a  "x40000;
	$alpha="000"x40000;
	$im3 = create_image_from_data Gtk::Gdk::ImlibImage($data,$alpha,$h,$w);

	$im3->render($w, $h);
	$p3 = $im3->move_image();
	$m3 = $im3->move_mask;

	$mypixmap = new Gtk::Pixmap $p3, $m3;
	$vbox->pack_start($mypixmap,0,0,20);
	$mypixmap->show;

	# Add a button
        $capture_button = new Gtk::Button "  Play  ";
        signal_connect $capture_button "clicked", \&update_image;
        $vbox->pack_start($capture_button,1,0,0);
        $capture_button->show;

	Gtk::Gdk->flush;

}

create_main_window;

main Gtk;