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)
34 , _output_audio_frame_rate (_audio_content->output_audio_frame_rate (f))
36 if (_audio_content->content_audio_frame_rate() != _output_audio_frame_rate) {
39 s << String::compose ("Will resample audio from %1 to %2", _audio_content->content_audio_frame_rate(), _output_audio_frame_rate);
40 _film->log()->log (s.str ());
42 /* We will be using planar float data when we call the
43 resampler. As far as I can see, the audio channel
44 layout is not necessary for our purposes; it seems
45 only to be used get the number of channels and
46 decide if rematrixing is needed. It won't be, since
47 input and output layouts are the same.
50 _swr_context = swr_alloc_set_opts (
52 av_get_default_channel_layout (MAX_AUDIO_CHANNELS),
54 _output_audio_frame_rate,
55 av_get_default_channel_layout (MAX_AUDIO_CHANNELS),
57 _audio_content->content_audio_frame_rate(),
61 swr_init (_swr_context);
67 AudioDecoder::~AudioDecoder ()
70 swr_free (&_swr_context);
77 AudioDecoder::process_end ()
81 shared_ptr<AudioBuffers> out (new AudioBuffers (_film->audio_mapping().dcp_channels(), 256));
84 int const frames = swr_convert (_swr_context, (uint8_t **) out->data(), 256, 0, 0);
87 throw EncodeError (_("could not run sample-rate converter"));
94 out->set_frames (frames);
103 AudioDecoder::emit_audio (shared_ptr<const AudioBuffers> data, Time time)
105 /* XXX: map audio to 5.1 */
107 /* Maybe sample-rate convert */
110 /* Compute the resampled frames count and add 32 for luck */
111 int const max_resampled_frames = ceil ((int64_t) data->frames() * _output_audio_frame_rate / _audio_content->content_audio_frame_rate()) + 32;
113 shared_ptr<AudioBuffers> resampled (new AudioBuffers (MAX_AUDIO_CHANNELS, max_resampled_frames));
116 int const resampled_frames = swr_convert (
117 _swr_context, (uint8_t **) resampled->data(), max_resampled_frames, (uint8_t const **) data->data(), data->frames()
120 if (resampled_frames < 0) {
121 throw EncodeError (_("could not run sample-rate converter"));
124 resampled->set_frames (resampled_frames);
126 /* And point our variables at the resampled audio */