Resize image using PHP

<?php
//  Include the class
include("resize-class.php");
//  1) Initialise / load image
$resizeObj = new resize('sample.jpg');
//  2) Resize image (options: exact, portrait, landscape, auto, crop)
$resizeObj -> resizeImage(200, 200, 'crop');
//  3) Save image
$resizeObj -> saveImage('sample-resized.jpg', 100);
?>