Write the correct MCA subdescriptors depending on active channels.

3 files changed, 174 insertions, 1 deletions

diff --git a/src/lib/reel_writer.cc b/src/lib/reel_writer.cc
index 9ffe1cdc5..8bd15a575 100644
--- a/src/lib/reel_writer.cc
+++ b/src/lib/reel_writer.cc
@@ -192,12 +192,25 @@ ReelWriter::ReelWriter (
 
 		DCPOMATIC_ASSERT (film()->directory());
 
+		auto mapped = film()->mapped_audio_channels();
+		std::vector<dcp::Channel> extra_active_channels;
+		auto add_if_mapped = [mapped, &extra_active_channels](dcp::Channel channel) {
+			if (std::find(mapped.begin(), mapped.end(), static_cast<int>(channel)) != mapped.end()) {
+				extra_active_channels.push_back(channel);
+			}
+		};
+
+		add_if_mapped(dcp::Channel::HI);
+		add_if_mapped(dcp::Channel::VI);
+		add_if_mapped(dcp::Channel::BSL);
+		add_if_mapped(dcp::Channel::BSR);
+
 		/* Write the sound asset into the film directory so that we leave the creation
 		   of the DCP directory until the last minute.
 		*/
 		_sound_asset_writer = _sound_asset->start_write (
 			film()->directory().get() / audio_asset_filename (_sound_asset, _reel_index, _reel_count, _content_summary),
-			film()->audio_channels(),
+			extra_active_channels,
 			film()->contains_atmos_content() ? dcp::SoundAsset::AtmosSync::ENABLED : dcp::SoundAsset::AtmosSync::DISABLED,
 			film()->limit_to_smpte_bv20() ? dcp::SoundAsset::MCASubDescriptors::DISABLED : dcp::SoundAsset::MCASubDescriptors::ENABLED
 			);
diff --git a/test/mca_subdescriptors_test.cc b/test/mca_subdescriptors_test.cc
new file mode 100644
index 000000000..7585aa1ab
--- /dev/null
+++ b/test/mca_subdescriptors_test.cc
@@ -0,0 +1,159 @@
+/*
+    Copyright (C) 2023 Carl Hetherington <cth@carlh.net>
+
+    This file is part of DCP-o-matic.
+
+    DCP-o-matic is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    DCP-o-matic is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
+
+*/
+
+
+#include "lib/audio_content.h"
+#include "lib/constants.h"
+#include "lib/content.h"
+#include "lib/content_factory.h"
+#include "lib/film.h"
+#include "test.h"
+#include <libcxml/cxml.h>
+#include <boost/test/unit_test.hpp>
+
+
+using std::shared_ptr;
+using std::string;
+using std::vector;
+
+
+static
+void
+test_descriptors(vector<dcp::Channel> channels, vector<string> mca_tag_symbols, string group_name)
+{
+	auto content = content_factory("test/data/flat_red.png");
+	for (auto i = 0U; i < channels.size(); ++i) {
+		content.push_back(content_factory("test/data/C.wav").front());
+	}
+	auto film = new_test_film2("mca_subdescriptors_written_correctly", content);
+	film->set_interop(false);
+
+	int N = 1;
+	for (auto channel: channels) {
+		auto mapping = AudioMapping(1, MAX_DCP_AUDIO_CHANNELS);
+		mapping.set(0, channel, 1);
+		content[N]->audio->set_mapping(mapping);
+		++N;
+	}
+
+	make_and_verify_dcp(film);
+
+	cxml::Document check("CompositionPlaylist", find_file(film->dir(film->dcp_name()), "cpl_"));
+	vector<string> cpl_mca_tag_symbols;
+
+	auto mca_sub_descriptors = check.node_child("ReelList")->node_child("Reel")->node_child("AssetList")->node_child("CompositionMetadataAsset")->node_child("MCASubDescriptors");
+
+	for (auto node: mca_sub_descriptors->node_children("AudioChannelLabelSubDescriptor")) {
+		cpl_mca_tag_symbols.push_back(node->string_child("MCATagSymbol"));
+	}
+
+	auto const cpl_group_name = mca_sub_descriptors->node_child("SoundfieldGroupLabelSubDescriptor")->string_child("MCATagSymbol");
+
+	BOOST_CHECK(cpl_mca_tag_symbols == mca_tag_symbols);
+	BOOST_CHECK(cpl_group_name == group_name);
+}
+
+
+BOOST_AUTO_TEST_CASE(mca_subdescriptors_written_correctly_mono)
+{
+	test_descriptors({ dcp::Channel::CENTRE }, { "chL", "chR", "chC", "chLFE", "chLs", "chRs" }, "sg51");
+}
+
+
+BOOST_AUTO_TEST_CASE(mca_subdescriptors_written_correctly_stereo)
+{
+	test_descriptors({ dcp::Channel::LEFT, dcp::Channel::RIGHT }, { "chL", "chR", "chC", "chLFE", "chLs", "chRs" }, "sg51");
+}
+
+
+BOOST_AUTO_TEST_CASE(mca_subdescriptors_written_correctly_51)
+{
+	test_descriptors(
+		{
+			dcp::Channel::LEFT,
+			dcp::Channel::RIGHT,
+			dcp::Channel::CENTRE,
+			dcp::Channel::LFE,
+			dcp::Channel::LS,
+			dcp::Channel::RS,
+		},
+		{ "chL", "chR", "chC", "chLFE", "chLs", "chRs" },
+		"sg51"
+		);
+}
+
+
+BOOST_AUTO_TEST_CASE(mca_subdescriptors_written_correctly_51_with_hi_vi)
+{
+	test_descriptors(
+		{
+			dcp::Channel::LEFT,
+			dcp::Channel::RIGHT,
+			dcp::Channel::CENTRE,
+			dcp::Channel::LFE,
+			dcp::Channel::LS,
+			dcp::Channel::RS,
+			dcp::Channel::HI,
+			dcp::Channel::VI,
+		},
+		{ "chL", "chR", "chC", "chLFE", "chLs", "chRs", "chHI", "chVIN" },
+		"sg51"
+		);
+}
+
+
+BOOST_AUTO_TEST_CASE(mca_subdescriptors_written_correctly_71)
+{
+	test_descriptors(
+		{
+			dcp::Channel::LEFT,
+			dcp::Channel::RIGHT,
+			dcp::Channel::CENTRE,
+			dcp::Channel::LFE,
+			dcp::Channel::LS,
+			dcp::Channel::RS,
+			dcp::Channel::BSL,
+			dcp::Channel::BSR,
+		},
+		{ "chL", "chR", "chC", "chLFE", "chLss", "chRss", "chLrs", "chRrs" },
+		"sg71"
+		);
+}
+
+
+BOOST_AUTO_TEST_CASE(mca_subdescriptors_written_correctly_71_with_hi_vi)
+{
+	test_descriptors(
+		{
+			dcp::Channel::LEFT,
+			dcp::Channel::RIGHT,
+			dcp::Channel::CENTRE,
+			dcp::Channel::LFE,
+			dcp::Channel::LS,
+			dcp::Channel::RS,
+			dcp::Channel::HI,
+			dcp::Channel::VI,
+			dcp::Channel::BSL,
+			dcp::Channel::BSR,
+		},
+		{ "chL", "chR", "chC", "chLFE", "chLss", "chRss", "chHI", "chVIN", "chLrs", "chRrs" },
+		"sg71"
+		);
+}
diff --git a/test/wscript b/test/wscript
index dc108acb6..9917e7802 100644
--- a/test/wscript
+++ b/test/wscript
@@ -112,6 +112,7 @@ def build(bld):
                  kdm_util_test.cc
                  low_bitrate_test.cc
                  markers_test.cc
+                 mca_subdescriptors_test.cc
                  no_use_video_test.cc
                  optimise_stills_test.cc
                  overlap_video_test.cc