From 4ae0193c125cc70176eb1660919d507fbf5378e4 Mon Sep 17 00:00:00 2001
From: Carl Hetherington <cth@carlh.net>
Date: Wed, 8 Nov 2023 00:18:22 +0100
Subject: [PATCH] Don't feed channels to leqm that we don't have a correction
 factor for (#2647).

---
 src/lib/audio_analyser.cc   | 15 +++++++--------
 src/lib/audio_analyser.h    |  1 +
 test/audio_analysis_test.cc | 24 ++++++++++++++++++++++++
 3 files changed, 32 insertions(+), 8 deletions(-)

diff --git a/src/lib/audio_analyser.cc b/src/lib/audio_analyser.cc
index 687da9cef..8cbc3145b 100644
--- a/src/lib/audio_analyser.cc
+++ b/src/lib/audio_analyser.cc
@@ -86,14 +86,14 @@ AudioAnalyser::AudioAnalyser (shared_ptr<const Film> film, shared_ptr<const Play
 		}
 	};
 
-	int leqm_channels = film->audio_channels();
+	_leqm_channels = film->audio_channels();
 	auto content = _playlist->content();
 	if (content.size() == 1 && content[0]->audio) {
-		leqm_channels = content[0]->audio->mapping().mapped_output_channels().size();
+		_leqm_channels = content[0]->audio->mapping().mapped_output_channels().size();
 	}
 
 	/* XXX: is this right?  Especially for more than 5.1? */
-	vector<double> channel_corrections(leqm_channels, 1);
+	vector<double> channel_corrections(_leqm_channels, 1);
 	add_if_required (channel_corrections,  4,   -3); // Ls
 	add_if_required (channel_corrections,  5,   -3); // Rs
 	add_if_required (channel_corrections,  6, -144); // HI
@@ -108,7 +108,7 @@ AudioAnalyser::AudioAnalyser (shared_ptr<const Film> film, shared_ptr<const Play
 	add_if_required (channel_corrections, 15, -144); // Unused
 
 	_leqm.reset(new leqm_nrt::Calculator(
-		leqm_channels,
+		_leqm_channels,
 		film->audio_frame_rate(),
 		24,
 		channel_corrections,
@@ -150,15 +150,14 @@ AudioAnalyser::analyse (shared_ptr<AudioBuffers> b, DCPTime time)
 #endif
 
 	int const frames = b->frames ();
-	int const channels = b->channels ();
-	vector<double> interleaved(frames * channels);
+	vector<double> interleaved(frames * _leqm_channels);
 
-	for (int j = 0; j < channels; ++j) {
+	for (int j = 0; j < _leqm_channels; ++j) {
 		float const* data = b->data(j);
 		for (int i = 0; i < frames; ++i) {
 			float s = data[i];
 
-			interleaved[i * channels + j] = s;
+			interleaved[i * _leqm_channels + j] = s;
 
 			float as = fabsf (s);
 			if (as < 10e-7) {
diff --git a/src/lib/audio_analyser.h b/src/lib/audio_analyser.h
index 01eec36b1..3568d853d 100644
--- a/src/lib/audio_analyser.h
+++ b/src/lib/audio_analyser.h
@@ -71,6 +71,7 @@ private:
 	Frame _samples_per_point = 1;
 
 	boost::scoped_ptr<leqm_nrt::Calculator> _leqm;
+	int _leqm_channels = 0;
 	Frame _done = 0;
 	std::vector<float> _sample_peak;
 	std::vector<Frame> _sample_peak_frame;
diff --git a/test/audio_analysis_test.cc b/test/audio_analysis_test.cc
index 39abe7e48..9ad37ec2e 100644
--- a/test/audio_analysis_test.cc
+++ b/test/audio_analysis_test.cc
@@ -31,6 +31,7 @@
 #include "lib/audio_analysis.h"
 #include "lib/audio_content.h"
 #include "lib/content_factory.h"
+#include "lib/dcp_content.h"
 #include "lib/dcp_content_type.h"
 #include "lib/ffmpeg_content.h"
 #include "lib/ffmpeg_content.h"
@@ -211,6 +212,29 @@ BOOST_AUTO_TEST_CASE (analyse_audio_leqm_test)
 }
 
 
+BOOST_AUTO_TEST_CASE(analyse_audio_leqm_same_with_empty_channels)
+{
+	auto dcp = make_shared<DCPContent>(TestPaths::private_data() / "JourneyToJah_TLR-1_F_EN-DE-FR_CH_51_2K_LOK_20140225_DGL_SMPTE_OV");
+	auto film = new_test_film2("analyse_audio_leqm_test2", { dcp });
+	film->set_audio_channels(8);
+
+	auto analyse = [film, dcp](int channels) {
+		film->set_audio_channels(channels);
+		auto playlist = make_shared<Playlist>();
+		playlist->add(film, dcp);
+		boost::signals2::connection c;
+		JobManager::instance()->analyse_audio(film, playlist, false, c, [](Job::Result) {});
+		BOOST_CHECK(!wait_for_jobs());
+		AudioAnalysis analysis(film->audio_analysis_path(playlist));
+		return analysis.leqm().get_value_or(0);
+	};
+
+	BOOST_CHECK_CLOSE(analyse( 6), 84.51411, 0.001);
+	BOOST_CHECK_CLOSE(analyse( 8), 84.51411, 0.001);
+	BOOST_CHECK_CLOSE(analyse(16), 84.51411, 0.001);
+}
+
+
 /** Bug #2364; a file with a lot of silent video at the end (about 50s worth)
  *  crashed the audio analysis with an OOM on Windows.
  */
-- 
2.30.2