如何使用PHP中的imagestring()函数水平绘制文本字符串图像？

<?php
   // Create the size of the image or blank image
   $img = imagecreate(700, 300);

   // Set the background color of the image
   $background_color = imagecolorallocate($img, 122, 122, 122);

   // Set the text color of the image
   $text_color = imagecolorallocate($img, 255, 255, 0);

   // Function to create an image that contains a string.
   imagestring($img, 10, 30, 60,"Tutorialspoint:Simply Easy Learning", $text_color);
   header("Content-Type: image/png");
   imagepng($img);
   imagedestroy($img);
?>