Triggers after photo(s) added to the album.
~~~
<?php
function my_component_init(){
ossn_register_callback('ossn:photo', 'add', 'my_component_cb');
}
function my_component_cb($callback, $type, array $params){
//$params[guid] contains OssnFiles guid for newly added photo.
//$params['album'] contains instance of OssnAlbum.
}
ossn_register_callback('ossn', 'init', 'my_component_init');
~~~