--- src/filter/facebl0r/facebl0r.cpp.orig    2018-07-14 20:49:01.564511495 +1000
+++ src/filter/facebl0r/facebl0r.cpp 2018-07-14 18:47:44.430685507 +1000
@@ -19,6 +19,7 @@
 #include <stdlib.h>
 #include <opencv/cv.h>
 #include <opencv/highgui.h>
+#include <opencv2/imgproc.hpp>
 
 
 #include <frei0r.hpp>