diff --git a/src/openalpr/config.h b/src/openalpr/config.h
index 2a1105c..ebcab63 100644
--- a/src/openalpr/config.h
+++ b/src/openalpr/config.h
@@ -119,7 +119,7 @@ namespace alpr
       bool debugShowImages;
       bool debugPauseOnFrame;
 
-      void debugOff(bool value);
+      void debugOff(bool value = true);
 
       std::string getKeypointsRuntimeDir();
       std::string getCascadeRuntimeDir();