Change subtitle SubtitleAsset API to return const Subtitle pointers; add subtitles_in_reel().

5 files changed, 109 insertions, 71 deletions

diff --git a/src/subtitle_asset.cc b/src/subtitle_asset.cc
index 59aff6be..fc9b972a 100644
--- a/src/subtitle_asset.cc
+++ b/src/subtitle_asset.cc
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2012-2019 Carl Hetherington <cth@carlh.net>
+    Copyright (C) 2012-2021 Carl Hetherington <cth@carlh.net>
 
     This file is part of libdcp.
 
@@ -41,6 +41,7 @@
 #include "subtitle_image.h"
 #include "dcp_assert.h"
 #include "load_font_node.h"
+#include "reel_asset.h"
 #include <asdcp/AS_DCP.h>
 #include <asdcp/KM_util.h>
 #include <libxml++/nodes/element.h>
@@ -56,6 +57,7 @@ using std::cerr;
 using std::map;
 using std::shared_ptr;
 using std::vector;
+using std::make_shared;
 using boost::shared_array;
 using boost::optional;
 using boost::lexical_cast;
@@ -407,11 +409,23 @@ SubtitleAsset::maybe_add_subtitle (string text, vector<ParseState> const & parse
 	}
 }
 
-vector<shared_ptr<Subtitle>>
+
+vector<shared_ptr<const Subtitle>>
+SubtitleAsset::subtitles () const
+{
+	vector<shared_ptr<const Subtitle>> s;
+	for (auto i: _subtitles) {
+		s.push_back (i);
+	}
+	return s;
+}
+
+
+vector<shared_ptr<const Subtitle>>
 SubtitleAsset::subtitles_during (Time from, Time to, bool starting) const
 {
-	vector<shared_ptr<Subtitle> > s;
-	BOOST_FOREACH (shared_ptr<Subtitle> i, _subtitles) {
+	vector<shared_ptr<const Subtitle>> s;
+	for (auto i: _subtitles) {
 		if ((starting && from <= i->in() && i->in() < to) || (!starting && i->out() >= from && i->in() <= to)) {
 			s.push_back (i);
 		}
@@ -420,6 +434,27 @@ SubtitleAsset::subtitles_during (Time from, Time to, bool starting) const
 	return s;
 }
 
+
+/* XXX: this needs a test */
+vector<shared_ptr<const Subtitle>>
+SubtitleAsset::subtitles_in_reel (shared_ptr<const dcp::ReelAsset> asset) const
+{
+	auto frame_rate = asset->edit_rate().as_float();
+	auto start = dcp::Time(asset->entry_point().get_value_or(0), frame_rate, time_code_rate());
+	auto during = subtitles_during (start, start + dcp::Time(asset->intrinsic_duration(), frame_rate, time_code_rate()), false);
+
+	vector<shared_ptr<const dcp::Subtitle>> corrected;
+	for (auto i: during) {
+		auto c = make_shared<dcp::Subtitle>(*i);
+		c->set_in (c->in() - start);
+		c->set_out (c->out() - start);
+		corrected.push_back (c);
+	}
+
+	return corrected;
+}
+
+
 void
 SubtitleAsset::add (shared_ptr<Subtitle> s)
 {
diff --git a/src/subtitle_asset.h b/src/subtitle_asset.h
index 60ddc357..02976f7d 100644
--- a/src/subtitle_asset.h
+++ b/src/subtitle_asset.h
@@ -62,6 +62,7 @@ class FontNode;
 class TextNode;
 class SubtitleNode;
 class LoadFontNode;
+class ReelAsset;
 
 namespace order {
 	class Part;
@@ -88,10 +89,9 @@ public:
 		NoteHandler note
 		) const;
 
-	std::vector<std::shared_ptr<Subtitle>> subtitles_during (Time from, Time to, bool starting) const;
-	std::vector<std::shared_ptr<Subtitle>> const & subtitles () const {
-		return _subtitles;
-	}
+	std::vector<std::shared_ptr<const Subtitle>> subtitles_during (Time from, Time to, bool starting) const;
+	std::vector<std::shared_ptr<const Subtitle>> subtitles_in_reel(std::shared_ptr<const dcp::ReelAsset> asset) const;
+	std::vector<std::shared_ptr<const Subtitle>> subtitles () const;
 
 	virtual void add (std::shared_ptr<Subtitle>);
 	virtual void add_font (std::string id, dcp::ArrayData data) = 0;
@@ -107,6 +107,8 @@ public:
 
 	virtual std::vector<std::shared_ptr<LoadFontNode>> load_font_nodes () const = 0;
 
+	virtual int time_code_rate () const = 0;
+
 	std::string raw_xml () const {
 		return _raw_xml;
 	}
diff --git a/test/read_interop_subtitle_test.cc b/test/read_interop_subtitle_test.cc
index ba097222..d37e60d4 100644
--- a/test/read_interop_subtitle_test.cc
+++ b/test/read_interop_subtitle_test.cc
@@ -62,8 +62,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test1)
 
 	auto s = subs.subtitles_during (dcp::Time (0, 0, 6, 1, 250), dcp::Time (0, 0, 6, 2, 250), false);
 	BOOST_REQUIRE_EQUAL (s.size(), 1);
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.front()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.front()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.front()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.front()), dcp::SubtitleString (
 				   string ("theFontId"),
 				   false,
 				   false,
@@ -87,8 +87,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test1)
 
 	s = subs.subtitles_during (dcp::Time (0, 0, 7, 190, 250), dcp::Time (0, 0, 7, 191, 250), false);
 	BOOST_REQUIRE_EQUAL (s.size(), 2);
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.front()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.front()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.front()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.front()), dcp::SubtitleString (
 				   string ("theFontId"),
 				   true,
 				   false,
@@ -109,8 +109,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test1)
 				   dcp::Time (0, 0, 0, 1, 250),
 				   dcp::Time (0, 0, 0, 1, 250)
 				   ));
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.back()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.back()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.back()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.back()), dcp::SubtitleString (
 				   string ("theFontId"),
 				   false,
 				   false,
@@ -134,8 +134,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test1)
 
 	s = subs.subtitles_during (dcp::Time (0, 0, 11, 95, 250), dcp::Time (0, 0, 11, 96, 250), false);
 	BOOST_REQUIRE_EQUAL (s.size(), 1);
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.back()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.back()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.back()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.back()), dcp::SubtitleString (
 				   string ("theFontId"),
 				   false,
 				   false,
@@ -159,8 +159,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test1)
 
 	s = subs.subtitles_during (dcp::Time (0, 0, 14, 42, 250), dcp::Time (0, 0, 14, 43, 250), false);
 	BOOST_REQUIRE_EQUAL (s.size(), 1);
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.back()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.back()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.back()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.back()), dcp::SubtitleString (
 				   string ("theFontId"),
 				   false,
 				   true,
@@ -190,8 +190,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test2)
 
 	auto s = subs.subtitles_during (dcp::Time (0, 0, 42, 100, 250), dcp::Time (0, 0, 42, 101, 250), false);
 	BOOST_REQUIRE_EQUAL (s.size(), 2);
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.front()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.front()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.front()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.front()), dcp::SubtitleString (
 				   string ("theFont"),
 				   true,
 				   false,
@@ -212,8 +212,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test2)
 				   dcp::Time (0, 0, 0, 0, 250),
 				   dcp::Time (0, 0, 0, 0, 250)
 				   ));
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.back()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.back()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.back()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.back()), dcp::SubtitleString (
 				   string ("theFont"),
 				   true,
 				   false,
@@ -237,8 +237,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test2)
 
 	s = subs.subtitles_during (dcp::Time (0, 0, 50, 50, 250), dcp::Time (0, 0, 50, 51, 250), false);
 	BOOST_REQUIRE_EQUAL (s.size(), 2);
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.front()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.front()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.front()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.front()), dcp::SubtitleString (
 				   string ("theFont"),
 				   true,
 				   false,
@@ -259,8 +259,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test2)
 				   dcp::Time (0, 0, 0, 0, 250),
 				   dcp::Time (0, 0, 0, 0, 250)
 				   ));
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.back()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.back()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.back()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.back()), dcp::SubtitleString (
 				   string ("theFont"),
 				   true,
 				   false,
@@ -284,8 +284,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test2)
 
 	s = subs.subtitles_during (dcp::Time (0, 1, 2, 300, 250), dcp::Time (0, 1, 2, 301, 250), false);
 	BOOST_REQUIRE_EQUAL (s.size(), 2);
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.front()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.front()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.front()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.front()), dcp::SubtitleString (
 				   string ("theFont"),
 				   true,
 				   false,
@@ -306,8 +306,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test2)
 				   dcp::Time (0, 0, 0, 0, 250),
 				   dcp::Time (0, 0, 0, 0, 250)
 				   ));
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.back()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.back()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.back()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.back()), dcp::SubtitleString (
 				   string ("theFont"),
 				   true,
 				   false,
@@ -331,8 +331,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test2)
 
 	s = subs.subtitles_during (dcp::Time (0, 1, 15, 50, 250), dcp::Time (0, 1, 15, 51, 250), false);
 	BOOST_REQUIRE_EQUAL (s.size(), 2);
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.front()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.front()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.front()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.front()), dcp::SubtitleString (
 				   string ("theFont"),
 				   true,
 				   false,
@@ -353,8 +353,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test2)
 				   dcp::Time (0, 0, 0, 0, 250),
 				   dcp::Time (0, 0, 0, 0, 250)
 				   ));
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.back()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.back()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.back()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.back()), dcp::SubtitleString (
 				   string ("theFont"),
 				   true,
 				   false,
@@ -378,8 +378,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test2)
 
 	s = subs.subtitles_during (dcp::Time (0, 1, 27, 200, 250), dcp::Time (0, 1, 27, 201, 250), false);
 	BOOST_REQUIRE_EQUAL (s.size(), 2);
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.front()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.front()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.front()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.front()), dcp::SubtitleString (
 				   string ("theFont"),
 				   true,
 				   false,
@@ -400,8 +400,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test2)
 				   dcp::Time (0, 0, 0, 0, 250),
 				   dcp::Time (0, 0, 0, 0, 250)
 				   ));
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.back()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.back()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.back()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.back()), dcp::SubtitleString (
 				   string ("theFont"),
 				   true,
 				   false,
@@ -425,8 +425,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test2)
 
 	s = subs.subtitles_during (dcp::Time (0, 1, 42, 300, 250), dcp::Time (0, 1, 42, 301, 250), false);
 	BOOST_REQUIRE_EQUAL (s.size(), 2);
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.front()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.front()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.front()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.front()), dcp::SubtitleString (
 				   string ("theFont"),
 				   false,
 				   false,
@@ -447,8 +447,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test2)
 				   dcp::Time (0, 0, 0, 0, 250),
 				   dcp::Time (0, 0, 0, 0, 250)
 				   ));
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.back()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.back()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.back()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.back()), dcp::SubtitleString (
 				   string ("theFont"),
 				   false,
 				   false,
@@ -472,8 +472,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test2)
 
 	s = subs.subtitles_during (dcp::Time (0, 1, 45, 200, 250), dcp::Time (0, 1, 45, 201, 250), false);
 	BOOST_REQUIRE_EQUAL (s.size(), 2);
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.front()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.front()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.front()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.front()), dcp::SubtitleString (
 				   string ("theFont"),
 				   false,
 				   false,
@@ -494,8 +494,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test2)
 				   dcp::Time (0, 0, 0, 0, 250),
 				   dcp::Time (0, 0, 0, 0, 250)
 				   ));
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.back()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.back()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.back()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.back()), dcp::SubtitleString (
 				   string ("theFont"),
 				   false,
 				   false,
@@ -519,8 +519,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test2)
 
 	s = subs.subtitles_during (dcp::Time (0, 1, 47, 249, 250), dcp::Time (0, 1, 47, 250, 250), false);
 	BOOST_REQUIRE_EQUAL (s.size(), 2);
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.front()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.front()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.front()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.front()), dcp::SubtitleString (
 				   string ("theFont"),
 				   false,
 				   false,
@@ -541,8 +541,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test2)
 				   dcp::Time (0, 0, 0, 0, 250),
 				   dcp::Time (0, 0, 0, 0, 250)
 				   ));
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.back()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.back()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.back()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.back()), dcp::SubtitleString (
 				   string ("theFont"),
 				   false,
 				   false,
@@ -566,8 +566,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test2)
 
 	s = subs.subtitles_during (dcp::Time (0, 2, 6, 210, 250), dcp::Time (0, 2, 6, 211, 250), false);
 	BOOST_REQUIRE_EQUAL (s.size(), 2);
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.front()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.front()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.front()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.front()), dcp::SubtitleString (
 				   string ("theFont"),
 				   true,
 				   false,
@@ -588,8 +588,8 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test2)
 				   dcp::Time (0, 0, 0, 0, 250),
 				   dcp::Time (0, 0, 0, 0, 250)
 				   ));
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(s.back()));
-	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<dcp::SubtitleString>(s.back()), dcp::SubtitleString (
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(s.back()));
+	BOOST_CHECK_EQUAL (*dynamic_pointer_cast<const dcp::SubtitleString>(s.back()), dcp::SubtitleString (
 				   string ("theFont"),
 				   true,
 				   false,
@@ -618,7 +618,7 @@ BOOST_AUTO_TEST_CASE (read_interop_subtitle_test3)
 	dcp::InteropSubtitleAsset subs ("test/data/subs3.xml");
 
 	BOOST_REQUIRE_EQUAL (subs.subtitles().size(), 1);
-	shared_ptr<dcp::SubtitleImage> si = dynamic_pointer_cast<dcp::SubtitleImage>(subs.subtitles().front());
+	auto si = dynamic_pointer_cast<const dcp::SubtitleImage>(subs.subtitles().front());
 	BOOST_REQUIRE (si);
 	BOOST_CHECK (si->png_image() == dcp::ArrayData("test/data/sub.png"));
 }
diff --git a/test/read_smpte_subtitle_test.cc b/test/read_smpte_subtitle_test.cc
index 8fbf0214..15fc5dd8 100644
--- a/test/read_smpte_subtitle_test.cc
+++ b/test/read_smpte_subtitle_test.cc
@@ -73,12 +73,12 @@ BOOST_AUTO_TEST_CASE (read_smpte_subtitle_test)
 	BOOST_CHECK_EQUAL (smpte_lfn->id, "theFontId");
 	BOOST_CHECK_EQUAL (smpte_lfn->urn, "9118bbce-4105-4a05-b37c-a5a6f75e1fea");
 	BOOST_REQUIRE_EQUAL (sc.subtitles().size(), 63);
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(sc.subtitles().front()));
-	BOOST_CHECK_EQUAL (dynamic_pointer_cast<dcp::SubtitleString>(sc.subtitles().front())->text(), "Noch mal.");
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(sc.subtitles().front()));
+	BOOST_CHECK_EQUAL (dynamic_pointer_cast<const dcp::SubtitleString>(sc.subtitles().front())->text(), "Noch mal.");
 	BOOST_CHECK_EQUAL (sc.subtitles().front()->in(), dcp::Time (0, 0, 25, 12, 25));
 	BOOST_CHECK_EQUAL (sc.subtitles().front()->out(), dcp::Time (0, 0, 26, 4, 25));
-	BOOST_REQUIRE (dynamic_pointer_cast<dcp::SubtitleString>(sc.subtitles().back()));
-	BOOST_CHECK_EQUAL (dynamic_pointer_cast<dcp::SubtitleString>(sc.subtitles().back())->text(), "Prochainement");
+	BOOST_REQUIRE (dynamic_pointer_cast<const dcp::SubtitleString>(sc.subtitles().back()));
+	BOOST_CHECK_EQUAL (dynamic_pointer_cast<const dcp::SubtitleString>(sc.subtitles().back())->text(), "Prochainement");
 	BOOST_CHECK_EQUAL (sc.subtitles().back()->in(), dcp::Time (0, 1, 57, 17, 25));
 	BOOST_CHECK_EQUAL (sc.subtitles().back()->out(), dcp::Time (0, 1, 58, 12, 25));
 }
@@ -88,34 +88,35 @@ BOOST_AUTO_TEST_CASE (read_smpte_subtitle_test2)
 {
 	dcp::SMPTESubtitleAsset sc (private_test / "olsson.xml");
 
-	BOOST_REQUIRE_EQUAL (sc.subtitles().size(), 6);
-	auto i = sc.subtitles().begin();
-	shared_ptr<dcp::SubtitleString> is = dynamic_pointer_cast<dcp::SubtitleString>(*i);
+	auto subs = sc.subtitles();
+	BOOST_REQUIRE_EQUAL (subs.size(), 6);
+	auto i = 0;
+	auto is = dynamic_pointer_cast<const dcp::SubtitleString>(subs[i]);
 	BOOST_REQUIRE (is);
 	BOOST_CHECK_EQUAL (is->text(), "Testing is ");
 	BOOST_CHECK (!is->italic());
 	++i;
-	is = dynamic_pointer_cast<dcp::SubtitleString>(*i);
+	is = dynamic_pointer_cast<const dcp::SubtitleString>(subs[i]);
 	BOOST_REQUIRE (is);
 	BOOST_CHECK_EQUAL (is->text(), "really");
 	BOOST_CHECK (is->italic());
 	++i;
-	is = dynamic_pointer_cast<dcp::SubtitleString>(*i);
+	is = dynamic_pointer_cast<const dcp::SubtitleString>(subs[i]);
 	BOOST_REQUIRE (is);
 	BOOST_CHECK_EQUAL (is->text(), " fun!");
 	BOOST_CHECK (!is->italic());
 	++i;
-	is = dynamic_pointer_cast<dcp::SubtitleString>(*i);
+	is = dynamic_pointer_cast<const dcp::SubtitleString>(subs[i]);
 	BOOST_REQUIRE (is);
 	BOOST_CHECK_EQUAL (is->text(), "This is the ");
 	BOOST_CHECK (!is->italic());
 	++i;
-	is = dynamic_pointer_cast<dcp::SubtitleString>(*i);
+	is = dynamic_pointer_cast<const dcp::SubtitleString>(subs[i]);
 	BOOST_REQUIRE (is);
 	BOOST_CHECK_EQUAL (is->text(), "second");
 	BOOST_CHECK (is->italic());
 	++i;
-	is = dynamic_pointer_cast<dcp::SubtitleString>(*i);
+	is = dynamic_pointer_cast<const dcp::SubtitleString>(subs[i]);
 	BOOST_REQUIRE (is);
 	BOOST_CHECK_EQUAL (is->text(), " line!");
 	BOOST_CHECK (!is->italic());
@@ -127,7 +128,7 @@ BOOST_AUTO_TEST_CASE (read_smpte_subtitle_test3)
 	dcp::SMPTESubtitleAsset subs ("test/data/subs.mxf");
 
 	BOOST_REQUIRE_EQUAL (subs.subtitles().size(), 1);
-	shared_ptr<dcp::SubtitleImage> si = dynamic_pointer_cast<dcp::SubtitleImage>(subs.subtitles().front());
+	auto si = dynamic_pointer_cast<const dcp::SubtitleImage>(subs.subtitles()[0]);
 	BOOST_REQUIRE (si);
 	BOOST_CHECK (si->png_image() == dcp::ArrayData("test/data/sub.png"));
 }
diff --git a/tools/dcpinfo.cc b/tools/dcpinfo.cc
index 18ed7886..5ca9b24f 100644
--- a/tools/dcpinfo.cc
+++ b/tools/dcpinfo.cc
@@ -259,14 +259,14 @@ main_subtitle (vector<string> const& only, shared_ptr<Reel> reel, bool list_subt
 			OUTPUT_SUBTITLE(" in %1\n", smpte->language().get());
 		}
 		if (list_subtitles) {
-			BOOST_FOREACH (shared_ptr<Subtitle> k, subs) {
-				shared_ptr<SubtitleString> ks = dynamic_pointer_cast<SubtitleString> (k);
+			for (auto k: subs) {
+				auto ks = dynamic_pointer_cast<const SubtitleString>(k);
 				if (ks) {
 					stringstream s;
 					s << *ks;
 					OUTPUT_SUBTITLE("%1\n", s.str());
 				}
-				shared_ptr<SubtitleImage> is = dynamic_pointer_cast<SubtitleImage> (k);
+				auto is = dynamic_pointer_cast<const SubtitleImage>(k);
 				if (is) {
 					stringstream s;
 					s << *is;