2 Copyright (C) 2013-2017 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 /** @file src/audio_merger.cc
21 * @brief AudioMerger class.
24 #include "audio_merger.h"
25 #include "dcpomatic_time.h"
34 using boost::shared_ptr;
35 using boost::optional;
37 // #define INSTRUMENT 1
39 AudioMerger::AudioMerger (int frame_rate)
40 : _frame_rate (frame_rate)
43 cout << "I/AM frame_rate " << frame_rate << "\n";
48 AudioMerger::frames (DCPTime t) const
50 return t.frames_floor (_frame_rate);
53 /** Pull audio up to a given time; after this call, no more data can be pushed
54 * before the specified time.
55 * @param time Time to pull up to.
56 * @return Blocks of merged audio up to `time'.
58 list<pair<shared_ptr<AudioBuffers>, DCPTime> >
59 AudioMerger::pull (DCPTime time)
62 std::cout << "I/AM pull " << time.get() << "\n";
64 list<pair<shared_ptr<AudioBuffers>, DCPTime> > out;
66 list<Buffer> new_buffers;
68 _buffers.sort (AudioMerger::BufferComparator());
69 BOOST_FOREACH (Buffer i, _buffers) {
70 if (i.period().to <= time) {
71 /* Completely within the pull period */
72 DCPOMATIC_ASSERT (i.audio->frames() > 0);
73 out.push_back (make_pair (i.audio, i.time));
74 } else if (i.time < time) {
75 /* Overlaps the end of the pull period */
76 shared_ptr<AudioBuffers> audio (new AudioBuffers (i.audio->channels(), frames(DCPTime(time - i.time))));
77 /* Though time > i.time, audio->frames() could be 0 if the difference in time is less than one frame */
78 if (audio->frames() > 0) {
79 audio->copy_from (i.audio.get(), audio->frames(), 0, 0);
80 out.push_back (make_pair (audio, i.time));
81 i.audio->trim_start (audio->frames ());
82 i.time += DCPTime::from_frames(audio->frames(), _frame_rate);
83 DCPOMATIC_ASSERT (i.audio->frames() > 0);
84 new_buffers.push_back (i);
88 DCPOMATIC_ASSERT (i.audio->frames() > 0);
89 new_buffers.push_back (i);
93 _buffers = new_buffers;
95 for (list<pair<shared_ptr<AudioBuffers>, DCPTime> >::const_iterator i = out.begin(); i != out.end(); ++i) {
96 DCPOMATIC_ASSERT (i->first->frames() > 0);
102 /** Push some data into the merger at a given time */
104 AudioMerger::push (boost::shared_ptr<const AudioBuffers> audio, DCPTime time)
107 std::cout << "I/AM push " << time.get() << " " << audio->frames() << "\n";
109 DCPOMATIC_ASSERT (audio->frames() > 0);
111 DCPTimePeriod period (time, time + DCPTime::from_frames (audio->frames(), _frame_rate));
113 /* Mix any overlapping parts of this new block with existing ones */
114 BOOST_FOREACH (Buffer i, _buffers) {
115 optional<DCPTimePeriod> overlap = i.period().overlap (period);
117 int32_t const offset = frames(DCPTime(overlap->from - i.time));
118 int32_t const frames_to_mix = frames(overlap->duration());
120 i.audio->accumulate_frames(audio.get(), frames_to_mix, 0, offset);
122 i.audio->accumulate_frames(audio.get(), frames_to_mix, offset, 0);
127 list<DCPTimePeriod> periods;
128 BOOST_FOREACH (Buffer i, _buffers) {
129 periods.push_back (i.period ());
132 /* Add the non-overlapping parts */
133 BOOST_FOREACH (DCPTimePeriod i, subtract (period, periods)) {
134 list<Buffer>::iterator before = _buffers.end();
135 list<Buffer>::iterator after = _buffers.end();
136 for (list<Buffer>::iterator j = _buffers.begin(); j != _buffers.end(); ++j) {
137 if (j->period().to == i.from) {
140 if (j->period().from == i.to) {
145 /* Get the part of audio that we want to use */
146 shared_ptr<AudioBuffers> part (new AudioBuffers (audio->channels(), frames(i.to) - frames(i.from)));
147 part->copy_from (audio.get(), part->frames(), frames(DCPTime(i.from - time)), 0);
149 if (before == _buffers.end() && after == _buffers.end()) {
150 if (part->frames() > 0) {
152 _buffers.push_back (Buffer (part, time, _frame_rate));
154 } else if (before != _buffers.end() && after == _buffers.end()) {
155 /* We have an existing buffer before this one; append new data to it */
156 before->audio->append (part);
157 } else if (before ==_buffers.end() && after != _buffers.end()) {
158 /* We have an existing buffer after this one; append it to the new data and replace */
159 part->append (after->audio);
163 /* We have existing buffers both before and after; coalesce them all */
164 before->audio->append (part);
165 before->audio->append (after->audio);
166 _buffers.erase (after);
172 AudioMerger::clear ()
175 cout << "I/AM clear\n";