-gst_rtsp_media_factory_construct transfer_ownership="1"
-gst_rtsp_media_factory_get_element transfer_ownership="1"
-gst_rtsp_media_mapping_find_factory transfer_ownership="1"
-gst_rtsp_media_mapping_find_media transfer_ownership="1"
-gst_rtsp_server_accept_client transfer_ownership="1"
-gst_rtsp_server_create_watch transfer_ownership="1"
-gst_rtsp_server_get_io_channel transfer_ownership="1"
+gst_rtsp_media_factory_construct transfer_ownership="1" nullable="1"
+gst_rtsp_media_factory_get_element transfer_ownership="1" nullable="1"
+gst_rtsp_media_mapping_find_factory transfer_ownership="1" nullable="1"
+gst_rtsp_media_mapping_find_media transfer_ownership="1" nullable="1"
+gst_rtsp_server_accept_client transfer_ownership="1" nullable="1"
+gst_rtsp_server_create_watch transfer_ownership="1" nullable="1"
+gst_rtsp_server_get_io_channel transfer_ownership="1" nullable="1"