diff --git a/YACReaderLibrary/properties_dialog.cpp b/YACReaderLibrary/properties_dialog.cpp
index 3d872496..5dee384e 100644
--- a/YACReaderLibrary/properties_dialog.cpp
+++ b/YACReaderLibrary/properties_dialog.cpp
@@ -305,7 +305,7 @@ void PropertiesDialog::createButtonBox()
 QImage blurred(const QImage &image, const QRect &rect, int radius, bool alphaOnly = false)
 {
     int tab[] = { 14, 10, 8, 6, 5, 5, 4, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2 };
-    int alpha = (radius < 1) ? 16 : (radius > 17) ? 1 : tab[radius - 1];
+    int alpha = (radius < 1) ? 16 : ((radius > 17) ? 1 : tab[radius - 1]);
 
     QImage result = image.convertToFormat(QImage::Format_ARGB32_Premultiplied);
     int r1 = rect.top();