typedef struct mlt_multitrack_s *mlt_multitrack;
typedef struct mlt_filter_s *mlt_filter;
typedef struct mlt_transition_s *mlt_transition;
-typedef struct mlt_consumer_s *mlt_consumer;
typedef struct mlt_tractor_s *mlt_tractor;
+typedef struct mlt_field_s *mlt_field;
+typedef struct mlt_consumer_s *mlt_consumer;
typedef void ( *mlt_destructor )( void * );
typedef char *( *mlt_serialiser )( void *, int length );