imagecreate() or image create in php

<?php
header("Content-Type: image/png");
$img = @imagecreate(110, 20)
  or die("you Can't Initialize new GD image stream");
$background_color = imagecolorallocate($img, 0, 0, 0);
$text_colour = imagecolorallocate($img, 233, 14, 91);
imagestring($img, 1, 5, 5, "hai how are you", $text_colour);
imagepng($img);
imagedestroy($img);
?>