Fix a crash due the assertion in emit_audio failing when applying

trims which do not land precisely on a DCP audio sample boundary
(at least, I think that's what triggers it).

3 files changed, 32 insertions, 5 deletions

diff --git a/src/lib/audio_ring_buffers.cc b/src/lib/audio_ring_buffers.cc
index d26fb9eb7..21c4b6a5c 100644
--- a/src/lib/audio_ring_buffers.cc
+++ b/src/lib/audio_ring_buffers.cc
@@ -46,10 +46,11 @@ AudioRingBuffers::put (shared_ptr<const AudioBuffers> data, DCPTime time, int fr
 
 	if (!_buffers.empty()) {
 		DCPOMATIC_ASSERT (_buffers.front().first->channels() == data->channels());
-		if ((_buffers.back().second + DCPTime::from_frames(_buffers.back().first->frames(), frame_rate)) != time) {
+		DCPTime const end = (_buffers.back().second + DCPTime::from_frames(_buffers.back().first->frames(), frame_rate));
+		if (labs(end.get() - time.get()) > 1) {
 			cout << "bad put " << to_string(_buffers.back().second) << " " << _buffers.back().first->frames() << " " << to_string(time) << "\n";
 		}
-		DCPOMATIC_ASSERT ((_buffers.back().second + DCPTime::from_frames(_buffers.back().first->frames(), frame_rate)) == time);
+		DCPOMATIC_ASSERT (labs(end.get() - time.get()) < 2);
 	}
 
 	_buffers.push_back(make_pair(data, time));
diff --git a/src/lib/player.cc b/src/lib/player.cc
index fa6c1b055..f80adcbf4 100644
--- a/src/lib/player.cc
+++ b/src/lib/player.cc
@@ -1093,12 +1093,12 @@ void
 Player::emit_audio (shared_ptr<AudioBuffers> data, DCPTime time)
 {
 	/* Log if the assert below is about to fail */
-	if (_last_audio_time && time != *_last_audio_time) {
+	if (_last_audio_time && labs(time.get() - _last_audio_time->get()) > 1) {
 		_film->log()->log(String::compose("Out-of-sequence emit %1 vs %2", to_string(time), to_string(*_last_audio_time)), LogEntry::TYPE_WARNING);
 	}
 
-	/* This audio must follow on from the previous */
-	DCPOMATIC_ASSERT (!_last_audio_time || time == *_last_audio_time);
+	/* This audio must follow on from the previous, allowing for half a sample (at 48kHz) leeway */
+	DCPOMATIC_ASSERT (!_last_audio_time || labs(time.get() - _last_audio_time->get()) < 2);
 	Audio (data, time, _film->audio_frame_rate());
 	_last_audio_time = time + DCPTime::from_frames (data->frames(), _film->audio_frame_rate());
 }
diff --git a/test/player_test.cc b/test/player_test.cc
index 7e2631cc9..9d6641cb2 100644
--- a/test/player_test.cc
+++ b/test/player_test.cc
@@ -37,6 +37,7 @@
 #include "lib/text_content.h"
 #include "lib/butler.h"
 #include "lib/compose.hpp"
+#include "lib/cross.h"
 #include "test.h"
 #include <boost/test/unit_test.hpp>
 #include <iostream>
@@ -317,3 +318,28 @@ BOOST_AUTO_TEST_CASE (player_ignore_video_and_audio_test)
 
 	BOOST_CHECK_EQUAL (out.size(), 6);
 }
+
+/** Trigger a crash due to the assertion failure in Player::emit_audio */
+BOOST_AUTO_TEST_CASE (player_trim_crash)
+{
+	shared_ptr<Film> film = new_test_film2 ("player_trim_crash");
+	shared_ptr<Content> boon = content_factory(private_data / "boon_telly.mkv").front();
+	film->examine_and_add_content (boon);
+	BOOST_REQUIRE (!wait_for_jobs());
+
+	shared_ptr<Player> player (new Player(film, film->playlist()));
+	player->set_fast ();
+	shared_ptr<Butler> butler (new Butler(player, AudioMapping(), 6, bind(&PlayerVideo::force, _1, AV_PIX_FMT_RGB24), false, true));
+
+	/* Wait for the butler to fill */
+	dcpomatic_sleep (5);
+
+	boon->set_trim_start (ContentTime::from_seconds(5));
+
+	butler->seek (DCPTime(), true);
+
+	/* Wait for the butler to refill */
+	dcpomatic_sleep (5);
+
+	butler->rethrow ();
+}