Permanently making alpha color transparent

[Morgon]

I'm having some trouble removing this color from an image.

If you look at the file, it seems just fine - however, you can see the color re-appear when loaded by Imagick:

Code: Select all

<?php
$im = new Imagick('bg.png');
header("Content-Type: image/png");
echo $im;

I can use paintTransparentImage() to hide it again, but even if I save it from Imagick, it doesn't actually go away.
How can I make this 'real' transparency?

Thank you!