In general the player assumes that it won't receive out of order video.

This clearly can happen with separate L/R sources.  A pass in L might
emit two frames which means the arrivals can't possibly be in order.

This commit fixes this by introducing a Shuffler which all alternate-3D
sources send their video to.  The Shuffler re-orders things before they
arrive at the player.

It also fixes the code which inserts video frames before one that arrives
after a gap.  This didn't cope with 3D right before.

The audio code solves a similar (perhaps the same?) problem with the
AudioMerger; perhaps we should have a similar thing for video and make
the player emit complete 3D frames.

Should help with #976.

2 files changed, 123 insertions, 0 deletions

diff --git a/test/shuffler_test.cc b/test/shuffler_test.cc
new file mode 100644
index 000000000..879f2e079
--- /dev/null
+++ b/test/shuffler_test.cc
@@ -0,0 +1,122 @@
+#include "lib/shuffler.h"
+#include "lib/piece.h"
+#include "lib/content_video.h"
+#include <boost/test/unit_test.hpp>
+
+using std::list;
+using boost::shared_ptr;
+using boost::weak_ptr;
+using boost::optional;
+
+static void
+push (Shuffler& s, int frame, Eyes eyes)
+{
+	shared_ptr<Piece> piece (new Piece (shared_ptr<Content>(), shared_ptr<Decoder>(), FrameRateChange(24, 24)));
+	ContentVideo cv;
+	cv.frame = frame;
+	cv.eyes = eyes;
+	s.video (piece, cv);
+}
+
+list<ContentVideo> pending_cv;
+
+static void
+receive (weak_ptr<Piece>, ContentVideo cv)
+{
+	pending_cv.push_back (cv);
+}
+
+static void
+check (int frame, Eyes eyes, int line)
+{
+	BOOST_REQUIRE_MESSAGE (!pending_cv.empty(), "Check at " << line << " failed.");
+	BOOST_CHECK_MESSAGE (pending_cv.front().frame == frame, "Check at " << line << " failed.");
+	BOOST_CHECK_MESSAGE (pending_cv.front().eyes == eyes, "Check at " << line << " failed.");
+	pending_cv.pop_front();
+}
+
+/** A perfect sequence */
+BOOST_AUTO_TEST_CASE (shuffler_test1)
+{
+	Shuffler s;
+	s.Video.connect (boost::bind (&receive, _1, _2));
+
+	for (int i = 0; i < 10; ++i) {
+		push (s, i, EYES_LEFT);
+		push (s, i, EYES_RIGHT);
+		check (i, EYES_LEFT, __LINE__);
+		check (i, EYES_RIGHT, __LINE__);
+	}
+}
+
+/** Everything present but some simple shuffling needed */
+BOOST_AUTO_TEST_CASE (shuffler_test2)
+{
+	Shuffler s;
+	s.Video.connect (boost::bind (&receive, _1, _2));
+
+	for (int i = 0; i < 10; i += 2) {
+		push (s, i, EYES_LEFT);
+		push (s, i + 1, EYES_LEFT);
+		push (s, i, EYES_RIGHT);
+		push (s, i + 1, EYES_RIGHT);
+		check (i, EYES_LEFT, __LINE__);
+		check (i, EYES_RIGHT, __LINE__);
+		check (i + 1, EYES_LEFT, __LINE__);
+		check (i + 1, EYES_RIGHT, __LINE__);
+	}
+}
+
+/** One missing left eye image */
+BOOST_AUTO_TEST_CASE (shuffler_test3)
+{
+	Shuffler s;
+	s.Video.connect (boost::bind (&receive, _1, _2));
+
+	push (s, 0, EYES_LEFT);
+	check (0, EYES_LEFT, __LINE__);
+	push (s, 0, EYES_RIGHT);
+	check (0, EYES_RIGHT, __LINE__);
+	push (s, 1, EYES_LEFT);
+	check (1, EYES_LEFT, __LINE__);
+	push (s, 1, EYES_RIGHT);
+	check (1, EYES_RIGHT, __LINE__);
+	push (s, 2, EYES_RIGHT);
+	push (s, 3, EYES_LEFT);
+	push (s, 3, EYES_RIGHT);
+	push (s, 4, EYES_LEFT);
+	push (s, 4, EYES_RIGHT);
+	s.flush ();
+	check (2, EYES_RIGHT, __LINE__);
+	check (3, EYES_LEFT, __LINE__);
+	check (3, EYES_RIGHT, __LINE__);
+	check (4, EYES_LEFT, __LINE__);
+	check (4, EYES_RIGHT, __LINE__);
+}
+
+/** One missing right eye image */
+BOOST_AUTO_TEST_CASE (shuffler_test4)
+{
+	Shuffler s;
+	s.Video.connect (boost::bind (&receive, _1, _2));
+
+	push (s, 0, EYES_LEFT);
+	check (0, EYES_LEFT, __LINE__);
+	push (s, 0, EYES_RIGHT);
+	check (0, EYES_RIGHT, __LINE__);
+	push (s, 1, EYES_LEFT);
+	check (1, EYES_LEFT, __LINE__);
+	push (s, 1, EYES_RIGHT);
+	check (1, EYES_RIGHT, __LINE__);
+	push (s, 2, EYES_LEFT);
+	push (s, 3, EYES_LEFT);
+	push (s, 3, EYES_RIGHT);
+	push (s, 4, EYES_LEFT);
+	push (s, 4, EYES_RIGHT);
+	s.flush ();
+	check (2, EYES_LEFT, __LINE__);
+	check (3, EYES_LEFT, __LINE__);
+	check (3, EYES_RIGHT, __LINE__);
+	check (4, EYES_LEFT, __LINE__);
+	check (4, EYES_RIGHT, __LINE__);
+}
diff --git a/test/wscript b/test/wscript
index f0533cfa1..fef16dbed 100644
--- a/test/wscript
+++ b/test/wscript
@@ -93,6 +93,7 @@ def build(bld):
                  render_subtitles_test.cc
                  scaling_test.cc
                  silence_padding_test.cc
+                 shuffler_test.cc
                  skip_frame_test.cc
                  srt_subtitle_test.cc
                  ssa_subtitle_test.cc