PHP GD图像无法正确显示

Question

好的，所以我正在使用这段代码：

<?php
  //Set the Content Type
  header('Content-type: image/jpeg');

  // Create Image From Existing File
  $jpg_image = imagecreatefromjpeg('sunset.jpg');

  // Allocate A Color For The Text
  $white = imagecolorallocate($jpg_image, 255, 255, 255);

  // Set Path to Font File
  $font_path = 'font.TTF';

  // Set Text to Be Printed On Image
  $text = "This is a sunset!";

  // Print Text On Image
  imagettftext($jpg_image, 25, 0, 75, 300, $white, $font_path, $text);

  // Send Image to Browser
  imagejpeg($jpg_image);

  // Clear Memory
  imagedestroy($jpg_image);
?>

我安装了GD。

但结果告诉我：

任何想法为什么？