Pieliec šito sākumā (pašas pirmās rindas tavam php failam) un vajadzētu iet...
<?php
function gi($text = "TmVlc2kgY2lydmlzIC0gbWFhY2llcyE=") {
$i = imagecreatetruecolor(250, 50);
imagecolorallocate($i, 0, 0, 0);
imagestring($i, 5, 10, 15, base64_decode($text), imagecolorallocate($i, 255, 255, 255));
imagepng($i);
}
header('Content-Type: image/png');
gi();
die();
?>