diff --git a/spectrogramplot.cpp b/spectrogramplot.cpp
index 6c03b5d..edf76d7 100644
--- a/spectrogramplot.cpp
+++ b/spectrogramplot.cpp
@@ -26,7 +26,7 @@
 #include <QPixmapCache>
 #include <QRect>
 #include <liquid/liquid.h>
-
+#include <functional>
 #include <cstdlib>
 #include "util.h"