Add header guards.

diff --git a/src/lib/audio_filter_graph.h b/src/lib/audio_filter_graph.h
index e749d0ec98bf27a918ebc9cfb1b1540544563e59..e5c55fa273b22009564b98fcce92f0f92bee3157 100644 (file)
--- a/src/lib/audio_filter_graph.h
+++ b/src/lib/audio_filter_graph.h
@@ -18,6 +18,11 @@
 
 */
 
+
+#ifndef DCPOMATIC_AUDIO_FILTER_GRAPH_H
+#define DCPOMATIC_AUDIO_FILTER_GRAPH_H
+
+
 #include "filter_graph.h"
 extern "C" {
 #include <libavfilter/buffersink.h>
@@ -45,3 +50,7 @@ private:
        int64_t _channel_layout;
        AVFrame* _in_frame;
 };
+
+
+#endif
+