#!/usr/bin/perl
use warnings;
use strict;
use GD;

GD::Image->trueColor(1);

my $img_file = 'zzrgbwb.png';

my $gd = GD::Image->new($img_file) or die;
my ($w, $h) = $gd->getBounds();
print "$w $h\n";

# allocate some colors
my $white = $gd->colorAllocate(255,255,255);
my $black = $gd->colorAllocate(0,0,0);
my $red = $gd->colorAllocate(255,0,0);
my $green = $gd->colorAllocate(0,255,0);
my $blue = $gd->colorAllocate(0,0,255);

# make the background transparent and interlaced
$gd->transparent($green);
#$gd->interlaced('true');

open(GD, ">zzrgbwb-gt.png") or die;
binmode GD;
print GD $gd->png;
close GD;