ardour/livetrax
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towards export latency compensation

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This commit is contained in:
Robin Gareus 2016-07-10 03:20:35 +02:00
parent 0a52b325f4
commit a4a246b41d
3 changed files with 33 additions and 0 deletions
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1
libs/ardour/ardour/session.h
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@ -1266,6 +1266,7 @@ class LIBARDOUR_API Session : public PBD::StatefulDestructible, public PBD::Scop
bool _exporting;
bool _export_rolling;
framepos_t _export_preroll;
framepos_t _export_latency;
boost::shared_ptr<ExportHandler> export_handler;
boost::shared_ptr<ExportStatus> export_status;

1
libs/ardour/session.cc
View File

@ -213,6 +213,7 @@ Session::Session (AudioEngine &eng,
, _exporting (false)
, _export_rolling (false)
, _export_preroll (0)
, _export_latency (0)
, _pre_export_mmc_enabled (false)
, _name (snapshot_name)
, _is_new (true)

31
libs/ardour/session_export.cc
View File

@ -111,6 +111,21 @@ Session::start_audio_export (framepos_t position)
}
_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 ();
/* 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
@ -212,9 +227,25 @@ Session::process_export_fw (pframes_t nframes)
butler_transport_work ();
g_atomic_int_set (&_butler->should_do_transport_work, 0);
post_transport ();
return 0;
}
if (_export_latency > 0) {
framepos_t remain = std::min ((framepos_t)nframes, _export_latency);
_engine.main_thread()->get_buffers ();
process_without_events (remain);
_engine.main_thread()->drop_buffers ();
_export_latency -= remain;
nframes -= remain;
if (nframes == 0) {
return 0;
}
}
_engine.main_thread()->get_buffers ();
process_export (nframes);
_engine.main_thread()->drop_buffers ();