diff --git a/src/Gui/BitmapFactory.cpp b/src/Gui/BitmapFactory.cpp
index 3fbfbf84a3..32dc01b75f 100644
--- a/src/Gui/BitmapFactory.cpp
+++ b/src/Gui/BitmapFactory.cpp
@@ -621,7 +621,11 @@ void BitmapFactoryInst::convert(const QImage& p, SoSFImage& img) const
     size[0] = p.width();
     size[1] = p.height();
 
+#if QT_VERSION >= QT_VERSION_CHECK(5, 10, 0)
+    int buffersize = static_cast<int>(p.sizeInBytes());
+#else
     int buffersize = p.byteCount();
+#endif
     int numcomponents = 0;
     QVector<QRgb> table = p.colorTable();
     if (!table.isEmpty()) {