<?
/*********************************************************************************************************
 This code is part of the GuestBook software (www.gerd-tentler.de/tools/guestbook), copyright by
 Gerd Tentler. Obtain permission before selling this code or hosting it on a commercial website or
 redistributing it over the Internet or in any other medium. In all cases copyright must remain intact.
*********************************************************************************************************/
/*
 ARGUMENTS: width  = thumbnail width
            height = thumbnail height
            file   = path to original image

 EXAMPLE:   <img src="thumbnail.php?width=200&height=100&file=images/image.jpg">
*/
  error_reporting(E_WARNING);

//========================================================================================================
// Set variables, if they are not registered globally; needs PHP 4.1.0 or higher
//========================================================================================================

  if(isset($_REQUEST['width'])) $width = $_REQUEST['width'];
  if(isset($_REQUEST['height'])) $height = $_REQUEST['height'];
  if(isset($_REQUEST['file'])) $file = $_REQUEST['file'];

//========================================================================================================
// Functions
//========================================================================================================

  function viewImage($img = '') {
    global $file, $type;

    switch($type) {
      case 1:
        if($img && function_exists('ImageGIF')) {
          header('Content-type: image/gif');
          @ImageGIF($img);
        }
        else if($img && function_exists('ImagePNG')) {
          header('Content-type: image/png');
          @ImagePNG($img);
        }
        else {
          header('Content-type: image/gif');
          readfile($file);
        }
      break;

      case 2:
        header('Content-type: image/jpeg');
        if($img && function_exists('ImageJPEG')) @ImageJPEG($img);
        else readfile($file);
      break;

      case 3:
        header('Content-type: image/png');
        if($img && function_exists('ImagePNG')) @ImagePNG($img);
        else readfile($file);
      break;

      default: echo "$file is not an image";
    }
  }

//========================================================================================================
// Main
//========================================================================================================

  list($src_width, $src_height, $type) = @getimagesize($file);

  if($src_width > $width || $src_height > $height) {
    $src_img = '';

    switch($type) {
      case 1:
        if(function_exists('ImageCreateFromGIF')) {
          $src_img = @ImageCreateFromGIF($file);
        }
        break;

      case 2:
        if(function_exists('ImageCreateFromJPEG')) {
          $src_img = @ImageCreateFromJPEG($file);
        }
        break;

      case 3:
        if(function_exists('ImageCreateFromPNG')) {
          $src_img = @ImageCreateFromPNG($file);
        }
        break;
    }

    if($src_img) {
      if($type != 1 && function_exists('ImageCreateTrueColor')) {
        $dst_img = @ImageCreateTrueColor($width, $height);
      }
      else $dst_img = @ImageCreate($width, $height);

      if(function_exists('ImageCopyResampled')) {
        @ImageCopyResampled($dst_img, $src_img, 0, 0, 0, 0, $width, $height, $src_width, $src_height);
      }
      else @ImageCopyResized($dst_img, $src_img, 0, 0, 0, 0, $width, $height, $src_width, $src_height);

      viewImage($dst_img);

      ImageDestroy($src_img);
      ImageDestroy($dst_img);
    }
    else viewImage();
  }
  else viewImage();
?>