From 9f034b0e2b39c2c56b767371af90deb888d8779f Mon Sep 17 00:00:00 2001
From: Carl Hetherington <cth@carlh.net>
Date: Wed, 14 Dec 2016 12:41:01 +0000
Subject: [PATCH] Store reel lengths in DCPContent to speed up e.g. timeline
 with many DCPs.

---
 src/lib/dcp_content.cc  | 32 +++++++++++++++++++++-----------
 src/lib/dcp_content.h   |  2 ++
 src/lib/dcp_examiner.cc |  8 ++++++++
 src/lib/dcp_examiner.h  |  5 +++++
 4 files changed, 36 insertions(+), 11 deletions(-)

diff --git a/src/lib/dcp_content.cc b/src/lib/dcp_content.cc
index 8c1b2d8a1..2eead3ee0 100644
--- a/src/lib/dcp_content.cc
+++ b/src/lib/dcp_content.cc
@@ -120,6 +120,9 @@ DCPContent::DCPContent (shared_ptr<const Film> film, cxml::ConstNodePtr node, in
 	}
 	_three_d = node->optional_bool_child("ThreeD").get_value_or (false);
 	_cpl = node->optional_string_child("CPL");
+	BOOST_FOREACH (cxml::ConstNodePtr i, node->node_children("ReelLength")) {
+		_reel_lengths.push_back (raw_convert<int64_t> (i->content ()));
+	}
 }
 
 void
@@ -172,6 +175,7 @@ DCPContent::examine (shared_ptr<Job> job)
 		_standard = examiner->standard ();
 		_three_d = examiner->three_d ();
 		_cpl = examiner->cpl ();
+		_reel_lengths = examiner->reel_lengths ();
 	}
 
 	if (needed_assets != needs_assets ()) {
@@ -253,6 +257,9 @@ DCPContent::as_xml (xmlpp::Node* node, bool with_paths) const
 	if (_cpl) {
 		node->add_child("CPL")->add_child_text (_cpl.get ());
 	}
+	BOOST_FOREACH (int64_t i, _reel_lengths) {
+		node->add_child("ReelLength")->add_child_text (raw_convert<string> (i));
+	}
 }
 
 DCPTime
@@ -363,17 +370,20 @@ DCPContent::set_reference_subtitle (bool r)
 list<DCPTimePeriod>
 DCPContent::reels () const
 {
-	list<DCPTimePeriod> p;
-	scoped_ptr<DCPDecoder> decoder;
-	try {
-		decoder.reset (new DCPDecoder (shared_from_this(), film()->log()));
-	} catch (...) {
-		/* Could not load the DCP; guess reels */
-		list<DCPTimePeriod> p;
-		p.push_back (DCPTimePeriod (position(), end()));
-		return p;
+	list<int64_t> reel_lengths = _reel_lengths;
+	if (reel_lengths.empty ()) {
+		/* Old metadata with no reel lengths; get them here instead */
+		try {
+			scoped_ptr<DCPExaminer> examiner (new DCPExaminer (shared_from_this()));
+			reel_lengths = examiner->reel_lengths ();
+		} catch (...) {
+			/* Could not examine the DCP; guess reels */
+			reel_lengths.push_back (length_after_trim().frames_round (film()->video_frame_rate ()));
+		}
 	}
 
+	list<DCPTimePeriod> p;
+
 	/* This content's frame rate must be the same as the output DCP rate, so we can
 	   convert `directly' from ContentTime to DCPTime.
 	*/
@@ -381,9 +391,9 @@ DCPContent::reels () const
 	/* The starting point of this content on the timeline */
 	DCPTime pos = position() - DCPTime (trim_start().get());
 
-	BOOST_FOREACH (shared_ptr<dcp::Reel> i, decoder->reels ()) {
+	BOOST_FOREACH (int64_t i, reel_lengths) {
 		/* This reel runs from `pos' to `to' */
-		DCPTime const to = pos + DCPTime::from_frames (i->main_picture()->duration(), film()->video_frame_rate());
+		DCPTime const to = pos + DCPTime::from_frames (i, film()->video_frame_rate());
 		if (to > position()) {
 			p.push_back (DCPTimePeriod (max(position(), pos), min(end(), to)));
 			if (to > end()) {
diff --git a/src/lib/dcp_content.h b/src/lib/dcp_content.h
index 1212b8b0f..ae8efa65e 100644
--- a/src/lib/dcp_content.h
+++ b/src/lib/dcp_content.h
@@ -168,6 +168,8 @@ private:
 	 *  just use the only CPL.
 	 */
 	boost::optional<std::string> _cpl;
+	/** List of the lengths of the reels in this DCP */
+	std::list<int64_t> _reel_lengths;
 };
 
 #endif
diff --git a/src/lib/dcp_examiner.cc b/src/lib/dcp_examiner.cc
index 74640ff00..996924530 100644
--- a/src/lib/dcp_examiner.cc
+++ b/src/lib/dcp_examiner.cc
@@ -163,6 +163,14 @@ DCPExaminer::DCPExaminer (shared_ptr<const DCPContent> content)
 
 			_has_subtitles = true;
 		}
+
+		if (i->main_picture()) {
+			_reel_lengths.push_back (i->main_picture()->duration());
+		} else if (i->main_sound()) {
+			_reel_lengths.push_back (i->main_sound()->duration());
+		} else if (i->main_subtitle()) {
+			_reel_lengths.push_back (i->main_subtitle()->duration());
+		}
 	}
 
 	_encrypted = cpl->encrypted ();
diff --git a/src/lib/dcp_examiner.h b/src/lib/dcp_examiner.h
index 0558bfcfc..d9c372c3c 100644
--- a/src/lib/dcp_examiner.h
+++ b/src/lib/dcp_examiner.h
@@ -93,6 +93,10 @@ public:
 		return _cpl;
 	}
 
+	std::list<int64_t> reel_lengths () const {
+		return _reel_lengths;
+	}
+
 private:
 	boost::optional<double> _video_frame_rate;
 	boost::optional<dcp::Size> _video_size;
@@ -108,4 +112,5 @@ private:
 	boost::optional<dcp::Standard> _standard;
 	bool _three_d;
 	std::string _cpl;
+	std::list<int64_t> _reel_lengths;
 };
-- 
2.30.2