get random images across pages optimized

RandomImages.module

<?php

/**
 * Example use:
 * 
 * $helper = $modules->get("RandomImages");
 * $image = $helper->getRandomImages(1,"images");
 * echo "<img src='{$image->size(150,0)->url}'>";
 */
 
class RandomImages extends WireData implements Module {

    public static function getModuleInfo() {

        return array(
            'title' => 'RandomImages',
            'version' => 1,
            'summary' => 'Get random images across pages. $image = getRandomImages(1,"images",1001);',
            'href' => '',
            'singular' => true
            );
    }

    public function init() { }

    public function getRandomImages($count=1, $field='images', $parent=1){
        $query = "SELECT i.pages_id,i.data FROM field_$field i
                LEFT JOIN pages p ON p.id = i.pages_id
                WHERE p.status < 2048
                AND p.parent_id in (SELECT pages_id FROM pages_parents WHERE parents_id=$parent OR pages_id=$parent)
                ORDER BY RAND() LIMIT $count";

        $res = wire("db")->query($query);
        if($res) {
            if($count > 1){
                $images = new WireArray();
                while($r = $res->fetch_array()){
                    $pid = $r['pages_id'];
                    $file = $r['data'];
                    $p = wire("pages")->get($pid);
                    $images->add($p->images->get($file));
                }
                return $images;
            } else {
                $r = $res->fetch_array();
                $pid = $r['pages_id'];
                $file = $r['data'];
                $p = wire("pages")->get($pid);
                $image = $p->images->get($file);
                return $image;
            }
        } else {
            return false;
        }
    }

}