PHP : Get Biggest image from URL

gistfile1.php

<?php
// Don't forget to install URL_to_Absolute
// Found at http://www.electrictoolbox.com/examples/url_to_absolute.zip 

function get_biggest_img($url){

require_once('simple_html_dom.php'); // PHP Simple HTML DOM Parser.
require_once('url_to_absolute/url_to_absolute.php'); // get image absolute url.
// options
$biggestImage = 'path to "no image found" image'; // Is returned when no images are found.
// process
$maxSize = -1;
$visited = array();
$html = file_get_html($url);
// loop images
foreach($html->find('img') as $element) {
    $src = $element->src;
    if($src=='')continue;// it happens on your test url
    $imageurl = url_to_absolute($url, $src);//get image absolute url
    // ignore already seen images, add new images
    if(in_array($imageurl, $visited))continue;
    $visited[]=$imageurl;
    // get image
    $image=@getimagesize($imageurl);// get the rest images width and height
    if (($image[0] * $image[1]) > $maxSize) {   
        $maxSize = $image[0] * $image[1];  //compare sizes
        $biggest_img = $imageurl;
    }
}
return $biggest_img; //return the biggest found image
}
?>