diff --git a/app/openbr-gui/imageviewer.h b/app/openbr-gui/imageviewer.h
index 43328bf..2e2d194 100644
--- a/app/openbr-gui/imageviewer.h
+++ b/app/openbr-gui/imageviewer.h
@@ -36,7 +36,6 @@ class BR_EXPORT_GUI ImageViewer : public QLabel
     Q_OBJECT
     QMutex mutex;
     QString defaultText;
-    QImage src;
 
 public:
     explicit ImageViewer(QWidget *parent = 0);
@@ -48,6 +47,9 @@ public:
     int imageWidth() const { return src.width(); }
     int imageHeight() const { return src.height(); }
 
+protected:
+    QImage src;
+
 protected slots:
     void keyPressEvent(QKeyEvent *event);
     void mouseMoveEvent(QMouseEvent *event);