#define MLT_PRODUCER(x) ( ( mlt_producer )( x ) )
#define MLT_MULTITRACK(x) ( ( mlt_multitrack )( x ) )
#define MLT_PLAYLIST(x) ( ( mlt_playlist )( x ) )
+#define MLT_TRACTOR(x) ( ( mlt_tractor )( x ) )
#define MLT_FILTER(x) ( ( mlt_filter )( x ) )
#define MLT_TRANSITION(x) ( ( mlt_transition )( x ) )