2 Copyright (C) 2012 Carl Hetherington <cth@carlh.net>
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 #include "audio_decoder.h"
21 #include "audio_buffers.h"
22 #include "exceptions.h"
27 using std::stringstream;
28 using boost::optional;
29 using boost::shared_ptr;
31 AudioDecoder::AudioDecoder (shared_ptr<const Film> f, shared_ptr<const AudioContent> c)
36 if (_audio_content->content_audio_frame_rate() != _audio_content->output_audio_frame_rate()) {
38 shared_ptr<const Film> film = _film.lock ();
42 s << String::compose (
43 "Will resample audio from %1 to %2",
44 _audio_content->content_audio_frame_rate(), _audio_content->output_audio_frame_rate()
47 film->log()->log (s.str ());
49 /* We will be using planar float data when we call the
50 resampler. As far as I can see, the audio channel
51 layout is not necessary for our purposes; it seems
52 only to be used get the number of channels and
53 decide if rematrixing is needed. It won't be, since
54 input and output layouts are the same.
57 _swr_context = swr_alloc_set_opts (
59 av_get_default_channel_layout (MAX_AUDIO_CHANNELS),
61 _audio_content->output_audio_frame_rate(),
62 av_get_default_channel_layout (MAX_AUDIO_CHANNELS),
64 _audio_content->content_audio_frame_rate(),
68 swr_init (_swr_context);
74 AudioDecoder::~AudioDecoder ()
77 swr_free (&_swr_context);
84 AudioDecoder::process_end ()
88 shared_ptr<const Film> film = _film.lock ();
91 shared_ptr<AudioBuffers> out (new AudioBuffers (film->audio_mapping().dcp_channels(), 256));
94 int const frames = swr_convert (_swr_context, (uint8_t **) out->data(), 256, 0, 0);
97 throw EncodeError (_("could not run sample-rate converter"));
104 out->set_frames (frames);
105 _writer->write (out);
113 AudioDecoder::audio (shared_ptr<const AudioBuffers> data, Time time)
118 /* Compute the resampled frames count and add 32 for luck */
119 int const max_resampled_frames = ceil (
120 (int64_t) data->frames() * _audio_content->output_audio_frame_rate() / _audio_content->content_audio_frame_rate()
123 shared_ptr<AudioBuffers> resampled (new AudioBuffers (data->channels(), max_resampled_frames));
126 int const resampled_frames = swr_convert (
127 _swr_context, (uint8_t **) resampled->data(), max_resampled_frames, (uint8_t const **) data->data(), data->frames()
130 if (resampled_frames < 0) {
131 throw EncodeError (_("could not run sample-rate converter"));
134 resampled->set_frames (resampled_frames);
136 /* And point our variables at the resampled audio */
140 shared_ptr<const Film> film = _film.lock ();
144 shared_ptr<AudioBuffers> dcp_mapped (film->dcp_audio_channels(), data->frames());
145 dcp_mapped->make_silent ();
146 list<pair<int, libdcp::Channel> > map = _audio_content->audio_mapping().content_to_dcp ();
147 for (list<pair<int, libdcp::Channel> >::iterator i = map.begin(); i != map.end(); ++i) {
148 dcp_mapped->accumulate (data, i->first, i->second);
151 Audio (dcp_mapped, time);
152 _next_audio = time + film->audio_frames_to_time (data->frames());