+ void load(const safe_ptr<frame_producer>& producer, bool play_on_load = false); // nothrow\r
+ void preview(const safe_ptr<frame_producer>& producer); // nothrow\r
+ void play(); // nothrow\r
+ void pause(); // nothrow\r
+ void stop(); // nothrow\r
+ void clear(); // nothrow\r
+\r
+ safe_ptr<frame_producer> foreground() const; // nothrow\r
+ safe_ptr<frame_producer> background() const; // nothrow\r