diff --git a/Code/Common/mvdQuicklookViewManipulator.h b/Code/Common/mvdQuicklookViewManipulator.h
index 43d840609ef1ae5cb5b3aaacea0934e1770470da..2aaf45118db9b65f924f06e378c3c9955f0a0b33 100644
--- a/Code/Common/mvdQuicklookViewManipulator.h
+++ b/Code/Common/mvdQuicklookViewManipulator.h
@@ -128,7 +128,7 @@ public slots:
 //
 // Signals.
 signals:
-  void ViewportRegionChanged(double Xpc, double Xpc);
+  void ViewportRegionChanged(double Xpc, double Ypc);
 
   /*-[ PROTECTED SECTION ]---------------------------------------------------*/