2 files changed, 11 insertions, 0 deletions
diff --git a/src/lib/film.cc b/src/lib/film.cc
index e8a23377d..b92d8d2fa 100644
--- a/src/lib/film.cc
+++ b/src/lib/film.cc
@@ -1076,6 +1076,16 @@ Film::set_dcp_frames (int f)
 }
 
 void
+Film::unset_dcp_frames ()
+{
+	{
+		boost::mutex::scoped_lock lm (_state_mutex);
+		_dcp_frames = boost::none;
+	}
+	signal_changed (DCP_FRAMES);
+}
+
+void
 Film::set_dcp_trim_action (TrimAction a)
 {
 	{
diff --git a/src/lib/film.h b/src/lib/film.h
index 131891706..3eff9e3da 100644
--- a/src/lib/film.h
+++ b/src/lib/film.h
@@ -349,6 +349,7 @@ public:
 	void set_filters (std::vector<Filter const *>);
 	void set_scaler (Scaler const *);
 	void set_dcp_frames (int);
+	void unset_dcp_frames ();
 	void set_dcp_trim_action (TrimAction);
 	void set_dcp_ab (bool);
 	void set_audio_stream (int);