<?php
  // Set the font file and font size for the text
  $font_file = '/path/to/font.ttf';
  $font_size = 12;

  // Create an array of image filenames
  $images = array('image1.png', 'image2.png', 'image3.png', 'image4.png', 'image5.png');

  // Select a random image filename from the array
  $random_image = $images[array_rand($images)];

  // Load the image using the GD library
  $image = imagecreatefrompng($random_image);

  // Get the width and height of the image
  $width = imagesx($image);
  $height = imagesy($image);

  // Send the appropriate HTTP headers and output the image
  header('Content-Type: image/png');
  imagepng($image);

  // Free up memory
  imagedestroy($image);
?>

代码运行良好，未出现任何错误，但当我加载代码时，仅出现此白色小方块。GD已启用，但不知道如何解决此问题。