Try to tidy up channel mapping a bit.

1 files changed, 14 insertions, 1 deletions

diff --git a/src/lib/util.h b/src/lib/util.h
index b76aead41..22c6ea95b 100644
--- a/src/lib/util.h
+++ b/src/lib/util.h
@@ -29,6 +29,7 @@
 #include <vector>
 #include <boost/shared_ptr.hpp>
 #include <boost/asio.hpp>
+#include <boost/optional.hpp>
 #include <libdcp/util.h>
 extern "C" {
 #include <libavcodec/avcodec.h>
@@ -179,7 +180,6 @@ struct Rect
 
 extern std::string crop_string (Position, libdcp::Size);
 extern int dcp_audio_sample_rate (int);
-extern int dcp_audio_channels (int);
 extern std::string colour_lut_index_to_name (int index);
 extern int stride_round_up (int, int const *, int);
 extern int stride_lookup (int c, int const * stride);
@@ -269,6 +269,19 @@ private:
 	float** _data;
 };
 
+class AudioMapping
+{
+public:
+	AudioMapping (int);
+
+	boost::optional<libdcp::Channel> source_to_dcp (int c) const;
+	boost::optional<int> dcp_to_source (libdcp::Channel c) const;
+	int dcp_channels () const;
+
+private:
+	int _source_channels;
+};
+
 extern int64_t video_frames_to_audio_frames (SourceFrame v, float audio_sample_rate, float frames_per_second);
 extern bool still_image_file (std::string);
 extern std::pair<std::string, int> cpu_info ();