PHP/Graphics Image/Image Paint

Image copy

<?php
$baseimage = ImageCreateFromPNG("logo.png");
$myImage = ImageCreateFromPNG("logo.png");
$gray = ImageColorAllocate($myImage, 18, 18, 18);
ImageColorTransparent($myImage, $gray);
ImageCopyMerge($baseimage,$myImage,0,0,0,0,15,15,10);
header ("Content-type: image/png");
ImagePNG($baseimage);
ImageDestroy($baseimage);
?>