pre-process (silence) before export to flush reverb tails etc.

diff --git a/libs/ardour/ardour/session.h b/libs/ardour/ardour/session.h
index d25f856b1fce7464c4eae59d81a43aa777658fa8..0651eb69bf0e6ef56be2bb2f2885d4d7a5c272bf 100644 (file)
--- a/libs/ardour/ardour/session.h
+++ b/libs/ardour/ardour/session.h
@@ -1195,8 +1195,8 @@ class LIBARDOUR_API Session : public PBD::StatefulDestructible, public PBD::Scop
        framepos_t post_export_position;
 
        bool _exporting;
-       bool _export_started;
        bool _export_rolling;
+       framepos_t _export_preroll;
 
        boost::shared_ptr<ExportHandler> export_handler;
        boost::shared_ptr<ExportStatus>  export_status;

diff --git a/libs/ardour/session.cc b/libs/ardour/session.cc
index d0fe74db2141850f5a1f77f4caf8db8be537f3db..bc17e4eb7fac517f6b38d69010f4670397aba0a1 100644 (file)
--- a/libs/ardour/session.cc
+++ b/libs/ardour/session.cc
@@ -204,8 +204,8 @@ Session::Session (AudioEngine &eng,
        , post_export_sync (false)
        , post_export_position (0)
        , _exporting (false)
-       , _export_started (false)
        , _export_rolling (false)
+       , _export_preroll (0)
        , _pre_export_mmc_enabled (false)
        , _name (snapshot_name)
        , _is_new (true)

diff --git a/libs/ardour/session_export.cc b/libs/ardour/session_export.cc
index 890871696517c7986622ef77212208df0ab08272..6b54db3826b8d923e16b78896d2ac39dea1a8214 100644 (file)
--- a/libs/ardour/session_export.cc
+++ b/libs/ardour/session_export.cc
@@ -73,12 +73,16 @@ Session::pre_export ()
                }
        }
 
-       /* make sure we are actually rolling */
+       /* prepare transport */
+
+       realtime_stop (true, true);
 
        if (get_record_enabled()) {
                disable_record (false);
        }
 
+       unset_play_loop ();
+
        /* no slaving */
 
        post_export_sync = config.get_external_sync ();
@@ -105,7 +109,8 @@ Session::start_audio_export (framepos_t position)
        if (!_exporting) {
                pre_export ();
        }
-       _export_started = false;
+
+       _export_preroll = 10.0 * nominal_frame_rate (); // TODO make configurable
 
        /* We're about to call Track::seek, so the butler must have finished everything
           up otherwise it could be doing do_refill in its thread while we are doing
@@ -190,8 +195,19 @@ Session::process_export (pframes_t nframes)
 int
 Session::process_export_fw (pframes_t nframes)
 {
-       if (!_export_started) {
-               _export_started = true;
+       if (_export_preroll > 0) {
+
+               _engine.main_thread()->get_buffers ();
+               fail_roll (nframes);
+               _engine.main_thread()->drop_buffers ();
+
+               _export_preroll -= std::min ((framepos_t)nframes, _export_preroll);
+
+               if (_export_preroll > 0) {
+                       // clear out buffers (reverb tails etc).
+                       return 0;
+               }
+
                set_transport_speed (1.0, 0, false);
                butler_transport_work ();
                g_atomic_int_set (&_butler->should_do_transport_work, 0);
@@ -199,9 +215,9 @@ Session::process_export_fw (pframes_t nframes)
                return 0;
        }
 
-        _engine.main_thread()->get_buffers ();
+       _engine.main_thread()->get_buffers ();
        process_export (nframes);
-        _engine.main_thread()->drop_buffers ();
+       _engine.main_thread()->drop_buffers ();
 
        return 0;
 }