Various attempted fixes to audio sync.

1 files changed, 17 insertions, 12 deletions

diff --git a/src/lib/audio_decoder.cc b/src/lib/audio_decoder.cc
index adabd5d99..8d3b0e128 100644
--- a/src/lib/audio_decoder.cc
+++ b/src/lib/audio_decoder.cc
@@ -37,7 +37,6 @@ using boost::shared_ptr;
 AudioDecoder::AudioDecoder (shared_ptr<const Film> film, shared_ptr<const AudioContent> content)
 	: Decoder (film)
 	, _audio_content (content)
-	, _audio_position (0)
 {
 	if (content->output_audio_frame_rate() != content->content_audio_frame_rate() && content->audio_channels ()) {
 		_resampler.reset (new Resampler (content->content_audio_frame_rate(), content->output_audio_frame_rate(), content->audio_channels ()));
@@ -47,16 +46,26 @@ AudioDecoder::AudioDecoder (shared_ptr<const Film> film, shared_ptr<const AudioC
 /** Audio timestamping is made hard by many factors, but the final nail in the coffin is resampling.
  *  We have to assume that we are feeding continuous data into the resampler, and so we get continuous
  *  data out.  Hence we do the timestamping here, post-resampler, just by counting samples.
+ *
+ *  The time is passed in here so that after a seek we can set up our _audio_position.  The
+ *  time is ignored once this has been done.
  */
 void
-AudioDecoder::audio (shared_ptr<const AudioBuffers> data)
+AudioDecoder::audio (shared_ptr<const AudioBuffers> data, ContentTime time)
 {
 	if (_resampler) {
 		data = _resampler->run (data);
 	}
 
-	_pending.push_back (shared_ptr<DecodedAudio> (new DecodedAudio (data, _audio_position)));
-	_audio_position += data->frames ();
+	if (!_audio_position) {
+		shared_ptr<const Film> film = _film.lock ();
+		assert (film);
+		FrameRateChange frc = film->active_frame_rate_change (_audio_content->position ());
+		_audio_position = (double (time) / frc.speed_up) * film->audio_frame_rate() / TIME_HZ;
+	}
+
+	_pending.push_back (shared_ptr<DecodedAudio> (new DecodedAudio (data, _audio_position.get ())));
+	_audio_position = _audio_position.get() + data->frames ();
 }
 
 void
@@ -68,17 +77,13 @@ AudioDecoder::flush ()
 
 	shared_ptr<const AudioBuffers> b = _resampler->flush ();
 	if (b) {
-		_pending.push_back (shared_ptr<DecodedAudio> (new DecodedAudio (b, _audio_position)));
-		_audio_position += b->frames ();
+		_pending.push_back (shared_ptr<DecodedAudio> (new DecodedAudio (b, _audio_position.get ())));
+		_audio_position = _audio_position.get() + b->frames ();
 	}
 }
 
 void
-AudioDecoder::seek (ContentTime t, bool)
+AudioDecoder::seek (ContentTime, bool)
 {
-	shared_ptr<const Film> film = _film.lock ();
-	assert (film);
-	
-	FrameRateChange frc = film->active_frame_rate_change (_audio_content->position ());
-	_audio_position = ((t + first_audio()) / frc.speed_up) * film->audio_frame_rate() / TIME_HZ;
+	_audio_position.reset ();
 }