diff --git a/openbr/plugins/gui.cpp b/openbr/plugins/gui.cpp
index d7bdd74..d3af3b2 100644
--- a/openbr/plugins/gui.cpp
+++ b/openbr/plugins/gui.cpp
@@ -176,6 +176,10 @@ public:
         setFixedSize(200,200);
         QApplication::instance()->installEventFilter(this);
     }
+    ~DisplayWindow()
+    {
+        QApplication::instance()->removeEventFilter(this);
+    }
 
 public slots:
     void showImage(const QPixmap & input)
@@ -193,7 +197,6 @@ public slots:
         setFixedSize(temp);
     }
 
-
     bool eventFilter(QObject * obj, QEvent * event)
     {
         if (event->type() == QEvent::KeyPress)
@@ -420,7 +423,10 @@ public:
     ~ShowTransform()
     {
         delete displayBuffer;
-        delete window;
+        if (QThread::currentThread() == QCoreApplication::instance()->thread())
+            delete window;
+        else
+            emit destroyWindow();
     }
 
     void train(const TemplateList &data) { (void) data; }
@@ -494,6 +500,7 @@ public:
         connect(this, SIGNAL(updateImage(QPixmap)), window,SLOT(showImage(QPixmap)));
         connect(this, SIGNAL(changeTitle(QString)), window, SLOT(setWindowTitle(QString)));
         connect(this, SIGNAL(hideWindow()), window, SLOT(hide()));
+        connect(this, SIGNAL(destroyWindow()), window, SLOT(deleteLater()), Qt::BlockingQueuedConnection);
     }
 
 protected:
@@ -506,6 +513,7 @@ signals:
     void updateImage(const QPixmap & input);
     void changeTitle(const QString & input);
     void hideWindow();
+    void destroyWindow();
 };
 BR_REGISTER(Transform, ShowTransform)