diff --git a/src/images/image.h b/src/images/image.h
index eb287db9..3081b831 100644
--- a/src/images/image.h
+++ b/src/images/image.h
@@ -1,100 +1,104 @@
 /***************************************************************************
     Copyright (C) 2003-2009 Robby Stephenson <robby@periapsis.org>
  ***************************************************************************/
 
 /***************************************************************************
  *                                                                         *
  *   This program is free software; you can redistribute it and/or         *
  *   modify it under the terms of the GNU General Public License as        *
  *   published by the Free Software Foundation; either version 2 of        *
  *   the License or (at your option) version 3 or any later version        *
  *   accepted by the membership of KDE e.V. (or its successor approved     *
  *   by the membership of KDE e.V.), which shall act as a proxy            *
  *   defined in Section 14 of version 3 of the license.                    *
  *                                                                         *
  *   This program is distributed in the hope that it will be useful,       *
  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  *   GNU General Public License for more details.                          *
  *                                                                         *
  *   You should have received a copy of the GNU General Public License     *
  *   along with this program.  If not, see <http://www.gnu.org/licenses/>. *
  *                                                                         *
  ***************************************************************************/
 
 #ifndef TELLICO_IMAGE_H
 #define TELLICO_IMAGE_H
 
 #include <QImage>
 #include <QString>
 #include <QByteArray>
 #include <QPixmap>
 
+#if (QT_VERSION < QT_VERSION_CHECK(5, 10, 0))
+using qsizetype = QIntegerForSizeof<std::size_t>::Signed;
+#endif
+
 namespace Tellico {
   class ImageFactory;
   class ImageDirectory;
   class ImageZipArchive;
   class FileHandler;
   class ImageJob;
 
   namespace Data {
 
 /**
  * @author Robby Stephenson
  */
 class Image : public QImage {
 
 friend class Tellico::ImageFactory;
 friend class Tellico::ImageDirectory;
 friend class Tellico::ImageZipArchive;
 friend class Tellico::FileHandler;
 friend class Tellico::ImageJob;
 
 public:
   ~Image();
 
   const QString& id() const { return m_id; };
   const QByteArray& format() const { return m_format; };
   QByteArray byteArray() const;
   bool isNull() const;
   bool linkOnly() const { return m_linkOnly; }
   void setLinkOnly(bool l) { m_linkOnly = l; }
   qsizetype byteSize() const;
 
   QPixmap convertToPixmap() const;
   QPixmap convertToPixmap(int width, int height) const;
 
   static QByteArray outputFormat(const QByteArray& inputFormat);
   static QByteArray byteArray(const QImage& img, const QByteArray& outputFormat);
   static QString idClean(const QString& id);
   static QString calculateID(const QByteArray& data, const QString& format);
 
   static const Image null;
 
 private:
   Image();
   Image(const Image& image);
   Image& operator=(const Image&);
   explicit Image(const QString& filename, const QString& id = QString());
   Image(const QImage& image, const QString& format);
   Image(const QByteArray& data, const QString& format, const QString& id);
 
   void setID(const QString& id);
   void setFormat(const QByteArray& format_) { m_format = format_; }
   void calculateID();
 
   QString m_id;
   QByteArray m_format;
   bool m_linkOnly : 1;
 
   static QList<QByteArray> s_outputFormats;
 };
 
   } // end namespace
 } // end namespace
 
 inline bool operator== (const Tellico::Data::Image& img1, const Tellico::Data::Image& img2) {
   return img1.id() == img2.id();
 }
 
 #endif