From 8e2c92bcbfe67a47e790ca842d6c99376789f2b7 Mon Sep 17 00:00:00 2001
From: Carl Hetherington <cth@carlh.net>
Date: Sat, 30 Nov 2019 20:25:48 +0100
Subject: [PATCH] Fix crash when exporting a 2D project containing 3D content
 (#1680).

---
 src/lib/ffmpeg_encoder.cc   | 16 +++++++++++++++-
 test/ffmpeg_encoder_test.cc | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 47 insertions(+), 1 deletion(-)

diff --git a/src/lib/ffmpeg_encoder.cc b/src/lib/ffmpeg_encoder.cc
index 3f5b6f591..4614903db 100644
--- a/src/lib/ffmpeg_encoder.cc
+++ b/src/lib/ffmpeg_encoder.cc
@@ -142,7 +142,10 @@ FFmpegEncoder::go ()
 
 		for (int j = 0; j < gets_per_frame; ++j) {
 			pair<shared_ptr<PlayerVideo>, DCPTime> v = _butler->get_video ();
-			encoder->get(v.first->eyes())->video(v.first, v.second);
+			shared_ptr<FFmpegFileEncoder> fe = encoder->get (v.first->eyes());
+			if (fe) {
+				fe->video(v.first, v.second);
+			}
 		}
 
 		_history.event ();
@@ -220,6 +223,17 @@ FFmpegEncoder::FileEncoderSet::FileEncoderSet (
 shared_ptr<FFmpegFileEncoder>
 FFmpegEncoder::FileEncoderSet::get (Eyes eyes) const
 {
+	if (_encoders.size() == 1) {
+		/* We are doing a 2D export... */
+		if (eyes == EYES_LEFT) {
+			/* ...but we got some 3D data; put the left eye into the output... */
+			eyes = EYES_BOTH;
+		} else if (eyes == EYES_RIGHT) {
+			/* ...and ignore the right eye.*/
+			return shared_ptr<FFmpegFileEncoder>();
+		}
+	}
+
 	map<Eyes, boost::shared_ptr<FFmpegFileEncoder> >::const_iterator i = _encoders.find (eyes);
 	DCPOMATIC_ASSERT (i != _encoders.end());
 	return i->second;
diff --git a/test/ffmpeg_encoder_test.cc b/test/ffmpeg_encoder_test.cc
index 1e001f0c8..d78b428c0 100644
--- a/test/ffmpeg_encoder_test.cc
+++ b/test/ffmpeg_encoder_test.cc
@@ -306,3 +306,35 @@ BOOST_AUTO_TEST_CASE (ffmpeg_encoder_h264_test6)
 	FFmpegEncoder encoder (film2, job, "build/test/ffmpeg_encoder_h264_test6_vf.mp4", EXPORT_FORMAT_H264, true, false, 23);
 	encoder.go ();
 }
+
+/** Test export of a 3D DCP in a 2D project */
+BOOST_AUTO_TEST_CASE (ffmpeg_encoder_h264_test7)
+{
+	shared_ptr<Film> film = new_test_film2 ("ffmpeg_encoder_h264_test7_data");
+	shared_ptr<Content> L (shared_ptr<ImageContent>(new ImageContent(private_data / "bbc405.png")));
+	film->examine_and_add_content (L);
+	shared_ptr<Content> R (shared_ptr<ImageContent>(new ImageContent(private_data / "bbc405.png")));
+	film->examine_and_add_content (R);
+	BOOST_REQUIRE (!wait_for_jobs());
+	L->video->set_frame_type (VIDEO_FRAME_TYPE_3D_LEFT);
+	L->set_position (film, DCPTime());
+	R->video->set_frame_type (VIDEO_FRAME_TYPE_3D_RIGHT);
+	R->set_position (film, DCPTime());
+	film->set_three_d (true);
+	film->make_dcp ();
+	BOOST_REQUIRE (!wait_for_jobs());
+
+	shared_ptr<Film> film2 = new_test_film2 ("ffmpeg_encoder_h264_test7_export");
+	shared_ptr<Content> dcp (new DCPContent(film->dir(film->dcp_name())));
+	film2->examine_and_add_content (dcp);
+	BOOST_REQUIRE (!wait_for_jobs());
+
+	shared_ptr<Job> job (new TranscodeJob (film2));
+	FFmpegEncoder encoder (film2, job, "build/test/ffmpeg_encoder_h264_test7.mp4", EXPORT_FORMAT_H264, true, false, 23
+#ifdef DCPOMATIC_VARIANT_SWAROOP
+			       , optional<dcp::Key>(), optional<string>()
+#endif
+		);
+	encoder.go ();
+}
+
-- 
2.30.2