<?PHP
function image_upload($userfile, $newfile, $directory, $width, $height, $quality='100', $smooth='10', $extention='AUTO') {
  $imgsize = GetImageSize($userfile);
  if (($imgsize[0] > $width) || ($imgsize[1] > $height)) {
    $tmpimg = tempnam("/tmp", "MKUP");
    system("djpeg $userfile >$tmpimg");
    system("pnmscale -xy $width $height $tmpimg | cjpeg -smoo $smooth -qual $quality >$userfile");
    unlink($tmpimg);
  };
  $mimetype = $_FILES['userfile']['type'];
  
  if ($extention == "AUTO") {
    if (($mimetype == "image/x-png") || ($mimetype == "image/png")){
      $extention = "png";
    }elseif ($mimetype == "image/pjpeg"){
      $extention = "jpg";
    }elseif ($mimetype == "image/gif"){
      $extention = "gif";
    }else{
      $extention = "";
      $error_message = "Please upload images with the extension .jpg or .jpeg or .gif or .png only";
    };
  };
  if (strstr($mimetype, "image/")) {
    $newfile_name = $newfile.".".$extention;
    $newfile = $directory.$newfile_name;
    if (is_uploaded_file($userfile)){
      if (!copy($userfile, $newfile)) {
        $error_message = "Error Uploading File.";
      };
    };
    return $newfile_name;
  }else{
    $error_message = "Not An Image";
  };
};

//EXAMPLE

image_upload($_FILE['userfile'], "Avatar-123", "images/avatars/", 90, 90, 100, 0)
?>