Verifica ou cadastra o usuario.

<?php

foreach($photos_users as $photo) {
        $friend_id = $photo['id'];
        $url_photo = $photo['url'];

        $sql_select = mysql_query('SELECT user_id, friend_id, friend_photo FROM friends WHERE user_id ='.$user.' AND(friend_id='.$friend_id.') LIMIT 4');

        while($array = mysql_fetch_array($sql_select))
        {  $count++; }

        if(!$count) {
            $avatar_friends = save_image("$url_photo", "../files/friends_$friend_id.png");

            $sql_insert = mysql_query("INSERT INTO friends(id, user_id, friend_id, friend_photo)
                            VALUES(NULL, '$user', '$friend_id', 'http://localhost/apps/timepovao/files/friends_$friend_id.png')");
            if($sql_insert) {
                $status['msg'] = "inserido com sucesso";
            } else {
                $status['msg'] = "erro ao cadastrar";
            }
        } else {
            $users = mysql_fetch_array($sql_select);
            foreach($users as $user) {
                print_r($user);
            }
            $status['msg'] = "já existem";
        }
    }

    echo json_encode($status);

}