I don't think there's a direct 'resize' method, but there's a 'copyResized' method that you can use to copy one image into another, resizing it in the process. If you have a PNG file for which you want to create a thumbnail 1/3 the size of the original, for example, you could do this:

    use GD;
    my $big = GD::Image->newFromPng($png_file)
        or die "Can't load PNG $png_file: $!";
    my($new_w, $new_h) = map { int($_/3) } $big->getBounds;
    my $small = GD::Image->new($new_w, $new_h);
    $small->copyResized($big, 0, 0, 0, 0, $new_w, $new_h, $big->getBou
+nds);
    print $small->png;
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That's just an example. A sort-of tested example. :)