diff --git a/openbr/plugins/gui.cpp b/openbr/plugins/gui.cpp
index ff5cf4b..11df368 100644
--- a/openbr/plugins/gui.cpp
+++ b/openbr/plugins/gui.cpp
@@ -136,7 +136,7 @@ public:
             QMouseEvent *mouseEvent = (QMouseEvent*)event;
 
             if (mouseEvent->button() == Qt::LeftButton) points.append(mouseEvent->pos());
-            else if (mouseEvent->button() == Qt::RightButton) points.removeLast();
+            else if (mouseEvent->button() == Qt::RightButton && !points.isEmpty()) points.removeLast();
 
             QPixmap pixmapBuffer = pixmap;