function resize($image,$width,$height = 0,$scale = false) {
   $src = @GetImageSize($image);
   $src_w = $src[0];
   $src_h = $src[1];
   if(is_array($src)) {
     $quotient = $src_w / $src_h;
     
     if($height==0) $height = $width * $quotient;
     if($width==0) $width = $height * $quotient;
     
     if($scale && $src_w < $width && $src_h < $height) {
       $src_w = $src_w + $width;
       $src_h = $src_h + $height;
     }
     if($src_w > $width) {
       $dst_w = $width;
       $dst_h = $dst_w / $quotient;
     }
     if($src_h > $height) {
       $dst_h = $height;
       $dst_w = $dst_h * $quotient;
     }

     if($src_h == $src_w) {
       $dst_h = $src_h;
       $dst_w = $src_w;
     }
     if ( $dst_h > $height || $dst_w > $width) {
       $dst_h = $height;
       $dst_w = $dst_h * $quotient;
       if ($dst_w > $width) {
         $dst_w = $width;
         $dst_h = $width / $quotient;
       }
     }
     if($src_w < $width && $src_h < $height) {
       $dst_w = $src_w;
       $dst_h = $src_h;
     }
     $dst = array("width" => $dst_w, "height" => $dst_h);
   }
   return $dst;
 }

 public static function resizeToFile($sourcefile, $dest_x, $dest_y, $targetfile = false, $endung = "jpg", $jpegqual = 90) {
   if(!$targetfile) $targetfile = $sourcefile;
   /* Get the dimensions of the source picture */
   $picsize=getimagesize("$sourcefile");

   $source_x = $picsize[0];
   $source_y  = $picsize[1];
   switch($endung) {
     case "gif": $source_id = imageCreateFromGIF("$sourcefile"); break;
     case "png": $source_id = imageCreateFromPNG("$sourcefile"); break;
     default: $source_id = imageCreateFromJPEG("$sourcefile");
   }
   $targetfile = str_replace($endung, "jpg", $targetfile);

   /* Create a new image object (not neccessarily true colour) */

   $target_id=imagecreatetruecolor($dest_x, $dest_y);

   /* Resize the original picture and copy it into the just created image
    object. Because of the lack of space I had to wrap the parameters to
    several lines. I recommend putting them in one line in order keep your
    code clean and readable */


   $target_pic=imagecopyresampled($target_id,$source_id, 0,0,0,0, $dest_x,$dest_y, $source_x,$source_y);

   /* Create a jpeg with the quality of "$jpegqual" out of the
    image object "$target_pic".
    This will be saved as $targetfile */

   imagejpeg ($target_id,"$targetfile",$jpegqual);

   return $targetfile;
 }