/*
- Copyright (C) 2013-2016 Carl Hetherington <cth@carlh.net>
+ Copyright (C) 2013-2017 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
using std::pair;
using std::min;
using std::max;
+using std::list;
+using std::cout;
using std::make_pair;
using boost::shared_ptr;
+using boost::optional;
-AudioMerger::AudioMerger (int channels, int frame_rate)
- : _buffers (new AudioBuffers (channels, 0))
- , _last_pull (0)
+AudioMerger::AudioMerger (int frame_rate)
+ : _last_pull (0)
, _frame_rate (frame_rate)
{
/** Pull audio up to a given time; after this call, no more data can be pushed
* before the specified time.
*/
-pair<shared_ptr<AudioBuffers>, DCPTime>
+list<pair<shared_ptr<AudioBuffers>, DCPTime> >
AudioMerger::pull (DCPTime time)
{
- /* Number of frames to return */
- Frame const to_return = time.frames_floor (_frame_rate) - _last_pull.frames_floor (_frame_rate);
- shared_ptr<AudioBuffers> out (new AudioBuffers (_buffers->channels(), to_return));
-
- /* And this is how many we will get from our buffer */
- Frame const to_return_from_buffers = min (to_return, Frame (_buffers->frames()));
-
- /* Copy the data that we have to the back end of the return buffer */
- out->copy_from (_buffers.get(), to_return_from_buffers, 0, to_return - to_return_from_buffers);
- /* Silence any gap at the start */
- out->make_silent (0, to_return - to_return_from_buffers);
-
- DCPTime 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;
+
+ DCPTimePeriod period (_last_pull, time);
+ _buffers.sort (AudioMerger::BufferComparator());
+
+ list<Buffer> new_buffers;
+
+ BOOST_FOREACH (Buffer i, _buffers) {
+ if (i.period().to < time) {
+ /* Completely within the pull period */
+ out.push_back (make_pair (i.audio, i.time));
+ } else if (i.time < time) {
+ /* Overlaps the end of the pull period */
+ shared_ptr<AudioBuffers> audio (new AudioBuffers (i.audio->channels(), DCPTime(time - i.time).frames_floor(_frame_rate)));
+ audio->copy_from (i.audio.get(), audio->frames(), 0, 0);
+ out.push_back (make_pair (audio, i.time));
+ i.audio->trim_start (audio->frames ());
+ i.time += DCPTime::from_frames(audio->frames(), _frame_rate);
+ new_buffers.push_back (i);
+ } else {
+ /* Not involved */
+ new_buffers.push_back (i);
+ }
}
- _buffers->set_frames (_buffers->frames() - to_return_from_buffers);
- return make_pair (out, out_time);
+ _buffers = new_buffers;
+ return out;
}
void
{
DCPOMATIC_ASSERT (time >= _last_pull);
- Frame const frame = time.frames_floor (_frame_rate);
- Frame after = max (Frame (_buffers->frames()), frame + audio->frames() - _last_pull.frames_floor (_frame_rate));
- _buffers->ensure_size (after);
- _buffers->accumulate_frames (audio.get(), 0, frame - _last_pull.frames_floor (_frame_rate), audio->frames ());
- _buffers->set_frames (after);
+ DCPTimePeriod period (time, time + DCPTime::from_frames (audio->frames(), _frame_rate));
+
+ /* Mix any parts of this new block with existing ones */
+ BOOST_FOREACH (Buffer i, _buffers) {
+ optional<DCPTimePeriod> overlap = i.period().overlap (period);
+ if (overlap) {
+ int32_t const offset = DCPTime(overlap->from - i.time).frames_floor(_frame_rate);
+ int32_t const frames = overlap->duration().frames_floor(_frame_rate);
+ if (i.time < time) {
+ i.audio->accumulate_frames(audio.get(), frames, 0, offset);
+ } else {
+ i.audio->accumulate_frames(audio.get(), frames, offset, 0);
+ }
+ }
+ }
+
+ list<DCPTimePeriod> periods;
+ BOOST_FOREACH (Buffer i, _buffers) {
+ periods.push_back (i.period ());
+ }
+
+ /* Add the non-overlapping parts */
+ BOOST_FOREACH (DCPTimePeriod i, subtract (period, periods)) {
+ list<Buffer>::iterator before = _buffers.end();
+ list<Buffer>::iterator after = _buffers.end();
+ for (list<Buffer>::iterator 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 */
+ shared_ptr<AudioBuffers> part (new AudioBuffers (audio->channels(), i.to.frames_floor(_frame_rate) - i.from.frames_floor(_frame_rate)));
+ part->copy_from (audio.get(), part->frames(), DCPTime(i.from - time).frames_floor(_frame_rate), 0);
+
+ if (before == _buffers.end() && after == _buffers.end()) {
+ /* 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);
+ }
+ }
}