Fix up AudioMapping confusions with respect to number of content channels.

5 files changed, 38 insertions, 20 deletions

diff --git a/src/lib/audio_mapping.cc b/src/lib/audio_mapping.cc
index 4630f17c1..7a5da7d2a 100644
--- a/src/lib/audio_mapping.cc
+++ b/src/lib/audio_mapping.cc
@@ -32,6 +32,7 @@ using boost::lexical_cast;
 using boost::dynamic_pointer_cast;
 
 AudioMapping::AudioMapping ()
+	: _content_channels (0)
 {
 
 }
@@ -40,13 +41,20 @@ AudioMapping::AudioMapping ()
  *  @param c Number of channels.
  */
 AudioMapping::AudioMapping (int c)
+	: _content_channels (c)
 {
-	if (c == 1) {
+
+}
+
+void
+AudioMapping::make_default ()
+{
+	if (_content_channels == 1) {
 		/* Mono -> Centre */
 		add (0, libdcp::CENTRE);
 	} else {
 		/* 1:1 mapping */
-		for (int i = 0; i < c; ++i) {
+		for (int i = 0; i < _content_channels; ++i) {
 			add (i, static_cast<libdcp::Channel> (i));
 		}
 	}
@@ -54,6 +62,8 @@ AudioMapping::AudioMapping (int c)
 
 AudioMapping::AudioMapping (shared_ptr<const cxml::Node> node)
 {
+	_content_channels = node->number_child<int> ("ContentChannels");
+	
 	list<shared_ptr<cxml::Node> > const c = node->node_children ("Map");
 	for (list<shared_ptr<cxml::Node> >::const_iterator i = c.begin(); i != c.end(); ++i) {
 		add ((*i)->number_child<int> ("ContentIndex"), static_cast<libdcp::Channel> ((*i)->number_child<int> ("DCP")));
@@ -79,22 +89,11 @@ AudioMapping::dcp_to_content (libdcp::Channel d) const
 	return c;
 }
 
-list<int>
-AudioMapping::content_channels () const
-{
-	list<int> c;
-	for (list<pair<int, libdcp::Channel> >::const_iterator i = _content_to_dcp.begin(); i != _content_to_dcp.end(); ++i) {
-		if (find (c.begin(), c.end(), i->first) == c.end ()) {
-			c.push_back (i->first);
-		}
-	}
-
-	return c;
-}
-
 list<libdcp::Channel>
 AudioMapping::content_to_dcp (int c) const
 {
+	assert (c < _content_channels);
+	
 	list<libdcp::Channel> d;
 	for (list<pair<int, libdcp::Channel> >::const_iterator i = _content_to_dcp.begin(); i != _content_to_dcp.end(); ++i) {
 		if (i->first == c) {
@@ -108,6 +107,8 @@ AudioMapping::content_to_dcp (int c) const
 void
 AudioMapping::as_xml (xmlpp::Node* node) const
 {
+	node->add_child ("ContentChannels")->add_child_text (lexical_cast<string> (_content_channels));
+	
 	for (list<pair<int, libdcp::Channel> >::const_iterator i = _content_to_dcp.begin(); i != _content_to_dcp.end(); ++i) {
 		xmlpp::Node* t = node->add_child ("Map");
 		t->add_child ("ContentIndex")->add_child_text (lexical_cast<string> (i->first));
diff --git a/src/lib/audio_mapping.h b/src/lib/audio_mapping.h
index ed2c3f28d..9a507b550 100644
--- a/src/lib/audio_mapping.h
+++ b/src/lib/audio_mapping.h
@@ -32,6 +32,11 @@ namespace cxml {
 	class Node;
 }
 
+/** A many-to-many mapping from some content channels to DCP channels.
+ *  The number of content channels is set on construction and fixed,
+ *  and then each of those content channels can be mapped to zero or
+ *  more DCP channels.
+ */
 class AudioMapping
 {
 public:
@@ -44,16 +49,21 @@ public:
 	void as_xml (xmlpp::Node *) const;
 
 	void add (int, libdcp::Channel);
+	void make_default ();
 
 	std::list<int> dcp_to_content (libdcp::Channel) const;
 	std::list<std::pair<int, libdcp::Channel> > content_to_dcp () const {
 		return _content_to_dcp;
 	}
 
-	std::list<int> content_channels () const;
+	int content_channels () const {
+		return _content_channels;
+	}
+	
 	std::list<libdcp::Channel> content_to_dcp (int) const;
 
 private:
+	int _content_channels;
 	std::list<std::pair<int, libdcp::Channel> > _content_to_dcp;
 };
 
diff --git a/src/lib/ffmpeg_content.cc b/src/lib/ffmpeg_content.cc
index 4c9b1d166..ebad8c8bd 100644
--- a/src/lib/ffmpeg_content.cc
+++ b/src/lib/ffmpeg_content.cc
@@ -281,12 +281,12 @@ operator== (FFmpegAudioStream const & a, FFmpegAudioStream const & b)
 }
 
 FFmpegAudioStream::FFmpegAudioStream (shared_ptr<const cxml::Node> node)
+	: mapping (node->node_child ("Mapping"))
 {
 	name = node->string_child ("Name");
 	id = node->number_child<int> ("Id");
 	frame_rate = node->number_child<int> ("FrameRate");
 	channels = node->number_child<int64_t> ("Channels");
-	mapping = AudioMapping (node->node_child ("Mapping"));
 	first_audio = node->optional_number_child<double> ("FirstAudio");
 }
 
diff --git a/src/lib/ffmpeg_content.h b/src/lib/ffmpeg_content.h
index bf550942a..1af586a71 100644
--- a/src/lib/ffmpeg_content.h
+++ b/src/lib/ffmpeg_content.h
@@ -24,6 +24,7 @@
 #include "video_content.h"
 #include "audio_content.h"
 #include "subtitle_content.h"
+#include "audio_mapping.h"
 
 class Filter;
 class ffmpeg_pts_offset_test;
@@ -37,7 +38,9 @@ public:
 		, frame_rate (f)
 		, channels (c)
 		, mapping (c)
-	{}
+	{
+		mapping.make_default ();
+	}
 
 	FFmpegAudioStream (boost::shared_ptr<const cxml::Node>);
 
@@ -52,8 +55,11 @@ public:
 
 private:
 	friend class ffmpeg_pts_offset_test;
+
 	/* Constructor for tests */
-	FFmpegAudioStream () {}
+	FFmpegAudioStream ()
+		: mapping (1)
+	{}
 };
 
 extern bool operator== (FFmpegAudioStream const & a, FFmpegAudioStream const & b);
diff --git a/src/lib/sndfile_content.cc b/src/lib/sndfile_content.cc
index 2dd7d8f67..7e6d56a9e 100644
--- a/src/lib/sndfile_content.cc
+++ b/src/lib/sndfile_content.cc
@@ -44,11 +44,11 @@ SndfileContent::SndfileContent (shared_ptr<const Film> f, boost::filesystem::pat
 SndfileContent::SndfileContent (shared_ptr<const Film> f, shared_ptr<const cxml::Node> node)
 	: Content (f, node)
 	, AudioContent (f, node)
+	, _audio_mapping (node->node_child ("AudioMapping"))
 {
 	_audio_channels = node->number_child<int> ("AudioChannels");
 	_audio_length = node->number_child<AudioContent::Frame> ("AudioLength");
 	_audio_frame_rate = node->number_child<int> ("AudioFrameRate");
-	_audio_mapping = AudioMapping (node->node_child ("AudioMapping"));
 }
 
 string
@@ -109,6 +109,7 @@ SndfileContent::examine (shared_ptr<Job> job)
 
 	/* XXX: do this in signal_changed...? */
 	_audio_mapping = AudioMapping (_audio_channels);
+	_audio_mapping.make_default ();
 	signal_changed (AudioContentProperty::AUDIO_MAPPING);
 }