Fix the build for older macOS.
[dcpomatic.git] / src / lib / audio_decoder.cc
index c33f68c01c0c0bd3e910c8e46b08774772c8688a..2d02043b5948d1071d0de18982e14abfcf03c12e 100644 (file)
 /*
-    Copyright (C) 2012 Carl Hetherington <cth@carlh.net>
+    Copyright (C) 2012-2021 Carl Hetherington <cth@carlh.net>
 
-    This program is free software; you can redistribute it and/or modify
+    This file is part of DCP-o-matic.
+
+    DCP-o-matic is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation; either version 2 of the License, or
     (at your option) any later version.
 
-    This program is distributed in the hope that it will be useful,
+    DCP-o-matic is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.
 
     You should have received a copy of the GNU General Public License
-    along with this program; if not, write to the Free Software
-    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+    along with DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
 
 */
 
+
 #include "audio_decoder.h"
 #include "audio_buffers.h"
-#include "exceptions.h"
+#include "audio_content.h"
+#include "dcpomatic_log.h"
 #include "log.h"
+#include "resampler.h"
+#include "compose.hpp"
+#include <iostream>
 
 #include "i18n.h"
 
-using std::stringstream;
+
+using std::cout;
+using std::shared_ptr;
+using std::make_shared;
 using boost::optional;
-using boost::shared_ptr;
+using namespace dcpomatic;
 
-AudioDecoder::AudioDecoder (shared_ptr<const Film> f, shared_ptr<const AudioContent> c)
-       : Decoder (f)
-       , _next_audio (0)
-       , _audio_content (c)
-       , _output_audio_frame_rate (_audio_content->output_audio_frame_rate (f))
+
+AudioDecoder::AudioDecoder (Decoder* parent, shared_ptr<const AudioContent> content, bool fast)
+       : DecoderPart (parent)
+       , _content (content)
+       , _fast (fast)
 {
-       if (_audio_content->content_audio_frame_rate() != _output_audio_frame_rate) {
+       /* Set up _positions so that we have one for each stream */
+       for (auto i: content->streams ()) {
+               _positions[i] = 0;
+       }
+}
 
-               shared_ptr<const Film> film = _film.lock ();
-               assert (film);
 
-               stringstream s;
-               s << String::compose ("Will resample audio from %1 to %2", _audio_content->content_audio_frame_rate(), _output_audio_frame_rate);
-               film->log()->log (s.str ());
+/** @param time_already_delayed true if the delay should not be added to time */
+void
+AudioDecoder::emit (shared_ptr<const Film> film, AudioStreamPtr stream, shared_ptr<const AudioBuffers> data, ContentTime time, bool time_already_delayed)
+{
+       if (ignore ()) {
+               return;
+       }
 
-               /* We will be using planar float data when we call the
-                  resampler.  As far as I can see, the audio channel
-                  layout is not necessary for our purposes; it seems
-                  only to be used get the number of channels and
-                  decide if rematrixing is needed.  It won't be, since
-                  input and output layouts are the same.
-               */
+       /* Amount of error we will tolerate on audio timestamps; see comment below.
+        * We'll use 1 24fps video frame at 48kHz as this seems to be roughly how
+        * ffplay does it.
+        */
+       static Frame const slack_frames = 48000 / 24;
+
+       int const resampled_rate = _content->resampled_frame_rate(film);
+       if (!time_already_delayed) {
+               time += ContentTime::from_seconds (_content->delay() / 1000.0);
+       }
 
-               _swr_context = swr_alloc_set_opts (
-                       0,
-                       av_get_default_channel_layout (MAX_AUDIO_CHANNELS),
-                       AV_SAMPLE_FMT_FLTP,
-                       _output_audio_frame_rate,
-                       av_get_default_channel_layout (MAX_AUDIO_CHANNELS),
-                       AV_SAMPLE_FMT_FLTP,
-                       _audio_content->content_audio_frame_rate(),
-                       0, 0
+       auto reset = false;
+       if (_positions[stream] == 0) {
+               /* This is the first data we have received since initialisation or seek.  Set
+                  the position based on the ContentTime that was given.  After this first time
+                  we just count samples unless the timestamp is more than slack_frames away
+                  from where we think it should be.  This is because ContentTimes seem to be
+                  slightly unreliable from FFmpegDecoder (i.e. not sample accurate), but we still
+                  need to obey them sometimes otherwise we get sync problems such as #1833.
+               */
+               if (_content->delay() > 0) {
+                       /* Insert silence to give the delay */
+                       silence (_content->delay ());
+               }
+               reset = true;
+       } else if (std::abs(_positions[stream] - time.frames_round(resampled_rate)) > slack_frames) {
+               reset = true;
+               LOG_GENERAL (
+                       "Reset audio position: was %1, new data at %2, slack: %3 frames",
+                       _positions[stream],
+                       time.frames_round(resampled_rate),
+                       std::abs(_positions[stream] - time.frames_round(resampled_rate))
                        );
-               
-               swr_init (_swr_context);
+       }
+
+       if (reset) {
+               _positions[stream] = time.frames_round (resampled_rate);
+       }
+
+       shared_ptr<Resampler> resampler;
+       auto i = _resamplers.find(stream);
+       if (i != _resamplers.end()) {
+               resampler = i->second;
        } else {
-               _swr_context = 0;
+               if (stream->frame_rate() != resampled_rate) {
+                       LOG_GENERAL (
+                               "Creating new resampler from %1 to %2 with %3 channels",
+                               stream->frame_rate(),
+                               resampled_rate,
+                               stream->channels()
+                               );
+
+                       resampler = make_shared<Resampler>(stream->frame_rate(), resampled_rate, stream->channels());
+                       if (_fast) {
+                               resampler->set_fast ();
+                       }
+                       _resamplers[stream] = resampler;
+               }
        }
-}
 
-AudioDecoder::~AudioDecoder ()
-{
-       if (_swr_context) {
-               swr_free (&_swr_context);
+       if (resampler) {
+               auto ro = resampler->run (data);
+               if (ro->frames() == 0) {
+                       return;
+               }
+               data = ro;
        }
+
+       Data(stream, ContentAudio (data, _positions[stream]));
+       _positions[stream] += data->frames();
 }
-       
 
-#if 0
-void
-AudioDecoder::process_end ()
+
+/** @return Time just after the last thing that was emitted from a given stream */
+ContentTime
+AudioDecoder::stream_position (shared_ptr<const Film> film, AudioStreamPtr stream) const
 {
-       if (_swr_context) {
-
-               shared_ptr<const Film> film = _film.lock ();
-               assert (film);
-               
-               shared_ptr<AudioBuffers> out (new AudioBuffers (film->audio_mapping().dcp_channels(), 256));
-                       
-               while (1) {
-                       int const frames = swr_convert (_swr_context, (uint8_t **) out->data(), 256, 0, 0);
-
-                       if (frames < 0) {
-                               throw EncodeError (_("could not run sample-rate converter"));
-                       }
+       auto i = _positions.find (stream);
+       DCPOMATIC_ASSERT (i != _positions.end ());
+       return ContentTime::from_frames (i->second, _content->resampled_frame_rate(film));
+}
 
-                       if (frames == 0) {
-                               break;
-                       }
 
-                       out->set_frames (frames);
-                       _writer->write (out);
+boost::optional<ContentTime>
+AudioDecoder::position (shared_ptr<const Film> film) const
+{
+       optional<ContentTime> p;
+       for (auto i: _positions) {
+               auto const ct = stream_position (film, i.first);
+               if (!p || ct < *p) {
+                       p = ct;
                }
-
        }
+
+       return p;
 }
-#endif
+
 
 void
-AudioDecoder::emit_audio (shared_ptr<const AudioBuffers> data, Time time)
+AudioDecoder::seek ()
 {
-       /* XXX: map audio to 5.1 */
-       
-       /* Maybe resample */
-       if (_swr_context) {
+       for (auto i: _resamplers) {
+               i.second->flush ();
+               i.second->reset ();
+       }
 
-               /* Compute the resampled frames count and add 32 for luck */
-               int const max_resampled_frames = ceil ((int64_t) data->frames() * _output_audio_frame_rate / _audio_content->content_audio_frame_rate()) + 32;
+       for (auto& i: _positions) {
+               i.second = 0;
+       }
+}
 
-               shared_ptr<AudioBuffers> resampled (new AudioBuffers (MAX_AUDIO_CHANNELS, max_resampled_frames));
 
-               /* Resample audio */
-               int const resampled_frames = swr_convert (
-                       _swr_context, (uint8_t **) resampled->data(), max_resampled_frames, (uint8_t const **) data->data(), data->frames()
-                       );
-               
-               if (resampled_frames < 0) {
-                       throw EncodeError (_("could not run sample-rate converter"));
+void
+AudioDecoder::flush ()
+{
+       for (auto const& i: _resamplers) {
+               auto ro = i.second->flush ();
+               if (ro->frames() > 0) {
+                       Data (i.first, ContentAudio (ro, _positions[i.first]));
+                       _positions[i.first] += ro->frames();
                }
+       }
 
-               resampled->set_frames (resampled_frames);
-               
-               /* And point our variables at the resampled audio */
-               data = resampled;
+       if (_content->delay() < 0) {
+               /* Finish off with the gap caused by the delay */
+               silence (-_content->delay ());
        }
+}
 
-       Audio (data, time);
 
-       shared_ptr<const Film> film = _film.lock ();
-       assert (film);
-       _next_audio = time + film->audio_frames_to_time (data->frames());
+void
+AudioDecoder::silence (int milliseconds)
+{
+       for (auto i: _content->streams()) {
+               int const samples = ContentTime::from_seconds(milliseconds / 1000.0).frames_round(i->frame_rate());
+               auto silence = make_shared<AudioBuffers>(i->channels(), samples);
+               silence->make_silent ();
+               Data (i, ContentAudio (silence, _positions[i]));
+       }
 }
-
-