Make terminate_threads() less likely to leave _threads containing invalid pointers.

[dcpomatic.git] / src / lib / audio_merger.cc

diff --git a/src/lib/audio_merger.cc b/src/lib/audio_merger.cc
index 5e0589bb12941e39481e74ac104700ab7a711ce7..a16c378c67309dac758c90abd27fc275ef7db769 100644 (file)
--- a/src/lib/audio_merger.cc
+++ b/src/lib/audio_merger.cc
@@ -17,6 +17,10 @@
 
 */
 
+/** @file  src/audio_merger.cc
+ *  @brief AudioMerger class.
+ */
+
 #include "audio_merger.h"
 #include "dcpomatic_time.h"
 #include <iostream>
@@ -31,64 +35,81 @@ using boost::shared_ptr;
 using boost::optional;
 
 AudioMerger::AudioMerger (int frame_rate)
-       : _last_pull (0)
-       , _frame_rate (frame_rate)
+       : _frame_rate (frame_rate)
 {
 
 }
 
+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)
 {
        list<pair<shared_ptr<AudioBuffers>, DCPTime> > out;
 
-       DCPTimePeriod period (_last_pull, time);
-       _buffers.sort (AudioMerger::BufferComparator());
-
        list<Buffer> new_buffers;
 
+       _buffers.sort (AudioMerger::BufferComparator());
        BOOST_FOREACH (Buffer i, _buffers) {
-               if (i.period().to < time) {
+               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 */
-                       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);
+                       shared_ptr<AudioBuffers> audio (new AudioBuffers (i.audio->channels(), frames(DCPTime(time - i.time))));
+                       /* Though time > i.time, audio->frames() could be 0 if the difference in time is less than one frame */
+                       if (audio->frames() > 0) {
+                               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);
+                               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 = new_buffers;
+
+       for (list<pair<shared_ptr<AudioBuffers>, DCPTime> >::const_iterator i = out.begin(); i != out.end(); ++i) {
+               DCPOMATIC_ASSERT (i->first->frames() > 0);
+       }
+
        return out;
 }
 
+/** Push some data into the merger at a given time */
 void
 AudioMerger::push (boost::shared_ptr<const AudioBuffers> audio, DCPTime time)
 {
-       DCPOMATIC_ASSERT (time >= _last_pull);
+       DCPOMATIC_ASSERT (audio->frames() > 0);
 
        DCPTimePeriod period (time, time + DCPTime::from_frames (audio->frames(), _frame_rate));
 
-       /* Mix any parts of this new block with existing ones */
+       /* Mix any overlapping 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);
+                       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, 0, offset);
+                               i.audio->accumulate_frames(audio.get(), frames_to_mix, 0, offset);
                        } else {
-                               i.audio->accumulate_frames(audio.get(), frames, offset, 0);
+                               i.audio->accumulate_frames(audio.get(), frames_to_mix, offset, 0);
                        }
                }
        }
@@ -112,11 +133,12 @@ AudioMerger::push (boost::shared_ptr<const AudioBuffers> audio, DCPTime time)
                }
 
                /* 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);
+               shared_ptr<AudioBuffers> part (new AudioBuffers (audio->channels(), frames(i.to) - frames(i.from)));
+               part->copy_from (audio.get(), part->frames(), frames(DCPTime(i.from - time)), 0);
 
                if (before == _buffers.end() && after == _buffers.end()) {
                        /* New buffer */
+                       DCPOMATIC_ASSERT (part->frames() > 0);
                        _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 */
@@ -134,3 +156,9 @@ AudioMerger::push (boost::shared_ptr<const AudioBuffers> audio, DCPTime time)
                }
        }
 }
+
+void
+AudioMerger::clear ()
+{
+       _buffers.clear ();
+}