diff --git a/core/dplugins/dimg/pgf/dimgpgfloader.h b/core/dplugins/dimg/pgf/dimgpgfloader.h
index 7bd48e22a2..c08e2f538b 100644
--- a/core/dplugins/dimg/pgf/dimgpgfloader.h
+++ b/core/dplugins/dimg/pgf/dimgpgfloader.h
@@ -1,69 +1,71 @@
 /* ============================================================
  *
  * This file is a part of digiKam project
  * https://www.digikam.org
  *
  * Date        : 2009-06-03
  * Description : A PGF IO file for DImg framework
  *
  * Copyright (C) 2009-2019 by Gilles Caulier <caulier dot gilles at gmail dot com>
  *
  * This implementation use LibPGF API <http://www.libpgf.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, or (at your option)
  * any later version.
  *
  * 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.
  *
  * ============================================================ */
 
 #ifndef DIGIKAM_DIMG_PGF_LOADER_H
 #define DIGIKAM_DIMG_PGF_LOADER_H
 
 // Local includes
 
 #include "dimg.h"
 #include "dimgloader.h"
 #include "digikam_export.h"
 
 using namespace Digikam;
 
 namespace Digikam
 {
 
 class DIGIKAM_EXPORT DImgPGFLoader : public DImgLoader
 {
 
 public:
 
     explicit DImgPGFLoader(DImg* const image);
     ~DImgPGFLoader();
 
     bool load(const QString& filePath, DImgLoaderObserver* const observer) override;
     bool save(const QString& filePath, DImgLoaderObserver* const observer) override;
 
-    virtual bool hasAlpha()   const override;
-    virtual bool sixteenBit() const override;
-    virtual bool isReadOnly() const override;
+    bool hasAlpha()   const override;
+    bool sixteenBit() const override;
+    bool isReadOnly() const override;
+
+private:
 
     bool progressCallback(double percent, bool escapeAllowed);
 
     static bool CallbackForLibPGF(double percent, bool escapeAllowed, void* data);
 
 private:
 
     bool                m_sixteenBit;
     bool                m_hasAlpha;
 
     DImgLoaderObserver* m_observer;
 };
 
 } // namespace Digikam
 
 #endif // DIGIKAM_DIMG_PGF_LOADER_H