/*
- Copyright (C) 2013-2014 Carl Hetherington <cth@carlh.net>
+ Copyright (C) 2013-2021 Carl Hetherington <cth@carlh.net>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
*/
-#include "audio_buffers.h"
+
+/** @file src/audio_merger.cc
+ * @brief AudioMerger class.
+ */
+
+
#include "audio_merger.h"
+#include "dcpomatic_time.h"
+#include <iostream>
-using std::min;
+
+using std::cout;
+using std::list;
+using std::make_pair;
+using std::make_shared;
using std::max;
-using boost::shared_ptr;
+using std::min;
+using std::pair;
+using std::shared_ptr;
+using boost::optional;
+using namespace dcpomatic;
-AudioMerger::AudioMerger (int channels, int frame_rate)
- : _buffers (new AudioBuffers (channels, 0))
- , _frame_rate (frame_rate)
- , _last_pull (0)
+
+AudioMerger::AudioMerger (int frame_rate)
+ : _frame_rate (frame_rate)
{
}
-TimedAudioBuffers
+Frame
+AudioMerger::frames (DCPTime t) const
+{
+ return t.frames_floor (_frame_rate);
+}
+
+
+/** Pull audio up to a given time; after this call, no more data can be pushed
+ * before the specified time.
+ * @param time Time to pull up to.
+ * @return Blocks of merged audio up to `time'.
+ */
+list<pair<shared_ptr<AudioBuffers>, DCPTime>>
AudioMerger::pull (DCPTime time)
{
- assert (time >= _last_pull);
-
- TimedAudioBuffers out;
-
- int64_t const to_return = DCPTime (time - _last_pull).frames (_frame_rate);
- out.audio.reset (new AudioBuffers (_buffers->channels(), to_return));
- /* And this is how many we will get from our buffer */
- int64_t const to_return_from_buffers = min (to_return, int64_t (_buffers->frames ()));
-
- /* Copy the data that we have to the back end of the return buffer */
- out.audio->copy_from (_buffers.get(), to_return_from_buffers, 0, to_return - to_return_from_buffers);
- /* Silence any gap at the start */
- out.audio->make_silent (0, to_return - to_return_from_buffers);
-
- out.time = _last_pull;
- _last_pull = time;
-
- /* And remove the data we're returning from our buffers */
- if (_buffers->frames() > to_return_from_buffers) {
- _buffers->move (to_return_from_buffers, 0, _buffers->frames() - to_return_from_buffers);
+ list<pair<shared_ptr<AudioBuffers>, DCPTime>> out;
+
+ list<Buffer> new_buffers;
+
+ _buffers.sort ([](Buffer const& a, Buffer const& b) {
+ return a.time < b.time;
+ });
+
+ for (auto i: _buffers) {
+ if (i.period().to <= time) {
+ /* Completely within the pull period */
+ DCPOMATIC_ASSERT (i.audio->frames() > 0);
+ out.push_back (make_pair (i.audio, i.time));
+ } else if (i.time < time) {
+ /* Overlaps the end of the pull period */
+ int32_t const overlap = frames(DCPTime(time - i.time));
+ /* Though time > i.time, overlap could be 0 if the difference in time is less than one frame */
+ if (overlap > 0) {
+ auto audio = make_shared<AudioBuffers>(i.audio, overlap, 0);
+ out.push_back (make_pair(audio, i.time));
+ i.audio->trim_start (overlap);
+ i.time += DCPTime::from_frames(overlap, _frame_rate);
+ DCPOMATIC_ASSERT (i.audio->frames() > 0);
+ new_buffers.push_back (i);
+ }
+ } else {
+ /* Not involved */
+ DCPOMATIC_ASSERT (i.audio->frames() > 0);
+ new_buffers.push_back (i);
+ }
}
- _buffers->set_frames (_buffers->frames() - to_return_from_buffers);
-
+
+ _buffers = new_buffers;
+
+ for (auto const& i: out) {
+ DCPOMATIC_ASSERT (i.first->frames() > 0);
+ }
+
return out;
}
+
+/** Push some data into the merger at a given time */
void
-AudioMerger::push (shared_ptr<const AudioBuffers> audio, DCPTime time)
+AudioMerger::push (std::shared_ptr<const AudioBuffers> audio, DCPTime time)
{
- assert (time >= _last_pull);
-
- int64_t frame = time.frames (_frame_rate);
- int64_t after = max (int64_t (_buffers->frames()), frame + audio->frames() - _last_pull.frames (_frame_rate));
- _buffers->ensure_size (after);
- _buffers->accumulate_frames (audio.get(), 0, frame - _last_pull.frames (_frame_rate), audio->frames ());
- _buffers->set_frames (after);
-}
+ DCPOMATIC_ASSERT (audio->frames() > 0);
-TimedAudioBuffers
-AudioMerger::flush ()
-{
- if (_buffers->frames() == 0) {
- return TimedAudioBuffers ();
+ DCPTimePeriod period (time, time + DCPTime::from_frames (audio->frames(), _frame_rate));
+
+ /* Mix any overlapping parts of this new block with existing ones */
+ for (auto i: _buffers) {
+ auto overlap = i.period().overlap(period);
+ if (overlap) {
+ int32_t const offset = frames(DCPTime(overlap->from - i.time));
+ int32_t const frames_to_mix = frames(overlap->duration());
+ if (i.time < time) {
+ i.audio->accumulate_frames(audio.get(), frames_to_mix, 0, offset);
+ } else {
+ i.audio->accumulate_frames(audio.get(), frames_to_mix, offset, 0);
+ }
+ }
+ }
+
+ list<DCPTimePeriod> periods;
+ for (auto i: _buffers) {
+ periods.push_back (i.period());
+ }
+
+ /* Add the non-overlapping parts */
+ for (auto i: subtract(period, periods)) {
+ auto before = _buffers.end();
+ auto after = _buffers.end();
+ for (auto j = _buffers.begin(); j != _buffers.end(); ++j) {
+ if (j->period().to == i.from) {
+ before = j;
+ }
+ if (j->period().from == i.to) {
+ after = j;
+ }
+ }
+
+ /* Get the part of audio that we want to use */
+ auto part = make_shared<AudioBuffers>(audio, frames(i.to) - frames(i.from), frames(DCPTime(i.from - time)));
+
+ if (before == _buffers.end() && after == _buffers.end()) {
+ if (part->frames() > 0) {
+ /* New buffer */
+ _buffers.push_back (Buffer (part, time, _frame_rate));
+ }
+ } else if (before != _buffers.end() && after == _buffers.end()) {
+ /* We have an existing buffer before this one; append new data to it */
+ before->audio->append (part);
+ } else if (before ==_buffers.end() && after != _buffers.end()) {
+ /* We have an existing buffer after this one; append it to the new data and replace */
+ part->append (after->audio);
+ after->audio = part;
+ after->time = time;
+ } else {
+ /* We have existing buffers both before and after; coalesce them all */
+ before->audio->append (part);
+ before->audio->append (after->audio);
+ _buffers.erase (after);
+ }
}
-
- return TimedAudioBuffers (_buffers, _last_pull);
}
+
void
-AudioMerger::clear (DCPTime t)
+AudioMerger::clear ()
{
- _last_pull = t;
- _buffers.reset (new AudioBuffers (_buffers->channels(), 0));
+ _buffers.clear ();
}
projects / dcpomatic.git / blobdiff