diff --git a/src/calibre/gui2/widgets.py b/src/calibre/gui2/widgets.py
index 6bc08aea3a..7cf363453a 100644
--- a/src/calibre/gui2/widgets.py
+++ b/src/calibre/gui2/widgets.py
@@ -343,9 +343,9 @@ class ImageView(QWidget, ImageDropMixin):  # {{{
         cw, ch = self.rect().width(), self.rect().height()
         scaled, nw, nh = fit_image(w, h, cw, ch)
         if scaled:
-            pmap = pmap.scaled(nw*pmap.devicePixelRatio(), nh*pmap.devicePixelRatio(), Qt.IgnoreAspectRatio,
+            pmap = pmap.scaled(int(nw*pmap.devicePixelRatio()), int(nh*pmap.devicePixelRatio()), Qt.IgnoreAspectRatio,
                     Qt.SmoothTransformation)
-        w, h = pmap.width()/pmap.devicePixelRatio(), pmap.height()/pmap.devicePixelRatio()
+        w, h = int(pmap.width()/pmap.devicePixelRatio()), int(pmap.height()/pmap.devicePixelRatio())
         x = int(abs(cw - w)/2.)
         y = int(abs(ch - h)/2.)
         target = QRect(x, y, w, h)