<?php
$img = imagecreatefrompng("php.png");
$width = imagesx($img);
$height = imagesy($img);
$img_copy = imagecreate($width * 4, $height * 4);
imagecopyresized($img_copy, $img, 0, 0, 0, 0, $width * 4, $height * 4, $width, $height);
header("Content-type: image/png");
imagepng($img_copy);
?>