+ _realtime_export = realtime;
+
+ if (realtime) {
+ _export_preroll = nominal_frame_rate ();
+ } else {
+ _export_preroll = Config->get_export_preroll() * nominal_frame_rate ();
+ }
+
+ if (_export_preroll == 0) {
+ // must be > 0 so that transport is started in sync.
+ _export_preroll = 1;
+ }
+
+ /* "worst_track_latency" is the correct value for stem-exports
+ * see to Route::add_export_point(),
+ *
+ * for master-bus export, we'd need to add the master's latency.
+ * or actually longest-total-session-latency.
+ *
+ * We can't use worst_playback_latency because that includes
+ * includes external latencies and would overcompensate.
+ */
+ _export_latency = worst_track_latency ();