function getImages($html) {
    $matches = array();
    $regex = '~http://somedomain.com/images/(.*?)\.jpg~i';
    preg_match_all($regex, $html, $matches);
    foreach ($matches[1] as $img) {
        saveImg($img);
    }
}

function saveImg($name) {
    $url = 'http://somedomain.com/images/'.$name.'.jpg';
    $data = get_data($url);
    file_put_contents('photos/'.$name.'.jpg', $data);
}

$i = 1;
$l = 101;

while ($i < $l) {
    $html = get_data('http://somedomain.com/id/'.$i.'/');
    getImages($html);
    $i += 1;
}

http://stackoverflow.com/questions/7747875/grab-download-images-from-multiple-pages-using-php-preg-match-all-curl

Here is a set of functions that can be very useful: Give this script the url of a webpage, and it will save all images from this page on your server.

Download and save images from a page using cURL

download, images

PHP