How to filter ads images when use `simple html dom` get site's images

I want use simple_html_dom to get some site's images. this is a test site. when I use some basic code below, I can get all开发者_如何转开发 the images. but how to filter ads images?

<?php
header('Content-type:text/html; charset=utf-8');
require_once 'simple_html_dom.php';
$v = 'http://www.vimeo.com/';
$html = file_get_html($v);
foreach($html->find('img') as $element) {
            $image = $element->src;
            echo '<img src="'.$image.'" /><hr />';
        }
?>

I notice some ads also as a jpg image format, but the url contains ad or ads, or something just as a gif image format... how to write some code to filter ads? thanks.

---

Search in your src if it find the ad(s) string. But that be too mush posibility, like admin,address,reading...

if (!preg_match("ads?", $element->src)) {
    //it's not an ad
}