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diff --git a/digikam/libs/dimg/dcolorblend.h b/digikam/libs/dimg/dcolorblend.h
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+/* ============================================================
+ *
+ * This file is a part of digiKam project
+ * http://www.digikam.org
+ *
+ * Date        : 2006-03-01
+ * Description : DColor methods for blending
+ *
+ * Copyright (C) 2006-2007 by Marcel Wiesweg <marcel.wiesweg@gmx.de>
+ *
+ * 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.
+ *
+ * ============================================================ */
+
+// Inspired by DirectFB, src/gfx/generic/generic.c:
+
+/*
+   (c) Copyright 2000-2002  convergence integrated media GmbH <curanz@convergence.de>
+   (c) Copyright 2002-2005  convergence GmbH.
+
+   All rights reserved.
+
+   Written by Denis Oliver Kropp <dok@directfb.org>,
+              Andreas Hundt <andi@fischlustig.de>,
+              Sven Neumann <neo@directfb.org>,
+              Ville Syrjälä <syrjala@sci.fi> and
+              Claudio Ciccani <klan@users.sf.net>.
+
+*/
+
+#ifndef DCOLORBLEND_H
+#define DCOLORBLEND_H
+
+namespace Digikam
+{
+
+inline void DColor::premultiply()
+{
+    if (sixteenBit())
+        premultiply16(alpha());
+    else
+        premultiply8(alpha());
+}
+
+inline void DColor::demultiply()
+{
+    if (sixteenBit())
+    {
+        demultiply16(alpha());
+        blendClamp16();
+    }
+    else
+    {
+        demultiply8(alpha());
+        blendClamp8();
+    }
+}
+
+inline void DColor::blendZero()
+{
+    setAlpha(0);
+    setRed(0);
+    setGreen(0);
+    setBlue(0);
+}
+
+inline void DColor::blendAlpha16(int alphaValue)
+{
+    uint Sa = alphaValue + 1;
+
+    setRed  ((Sa * (uint)red()) >> 16);
+    setGreen((Sa * (uint)green()) >> 16);
+    setBlue ((Sa * (uint)blue()) >> 16);
+    setAlpha((Sa * (uint)alpha()) >> 16);
+}
+
+inline void DColor::blendAlpha8(int alphaValue)
+{
+    uint Sa = alphaValue + 1;
+
+    setRed  ((Sa * red()) >> 8);
+    setGreen((Sa * green()) >> 8);
+    setBlue ((Sa * blue()) >> 8);
+    setAlpha((Sa * alpha()) >> 8);
+}
+
+inline void DColor::blendInvAlpha16(int alphaValue)
+{
+    uint Sa = 65536 - alphaValue;
+
+    setRed  ((Sa * (uint)red()) >> 16);
+    setGreen((Sa * (uint)green()) >> 16);
+    setBlue ((Sa * (uint)blue()) >> 16);
+    setAlpha((Sa * (uint)alpha()) >> 16);
+}
+
+inline void DColor::blendInvAlpha8(int alphaValue)
+{
+    uint Sa = 256 - alphaValue;
+
+    setRed  ((Sa * red()) >> 8);
+    setGreen((Sa * green()) >> 8);
+    setBlue ((Sa * blue()) >> 8);
+    setAlpha((Sa * alpha()) >> 8);
+}
+
+inline void DColor::premultiply16(int alphaValue)
+{
+    uint Da = alphaValue + 1;
+
+    setRed  ((Da * (uint)red()) >> 16);
+    setGreen((Da * (uint)green()) >> 16);
+    setBlue ((Da * (uint)blue()) >> 16);
+}
+
+inline void DColor::premultiply8(int alphaValue)
+{
+    uint Da = alphaValue + 1;
+
+    setRed  ((Da * red()) >> 8);
+    setGreen((Da * green()) >> 8);
+    setBlue ((Da * blue()) >> 8);
+}
+
+inline void DColor::demultiply16(int alphaValue)
+{
+    uint Da = alphaValue + 1;
+
+    setRed  (((uint)red()   << 16) / Da);
+    setGreen(((uint)green() << 16) / Da);
+    setBlue (((uint)blue()  << 16) / Da);
+}
+
+inline void DColor::demultiply8(int alphaValue)
+{
+    uint Da = alphaValue + 1;
+
+    setRed  ((red()   << 8) / Da);
+    setGreen((green() << 8) / Da);
+    setBlue ((blue()  << 8) / Da);
+}
+
+inline void DColor::blendAdd(const DColor &src)
+{
+    setRed  (red()   + src.red());
+    setGreen(green() + src.green());
+    setBlue (blue()  + src.blue());
+    setAlpha(alpha() + src.alpha());
+}
+
+inline void DColor::blendClamp16()
+{
+    if (0xFFFF0000 & red())   setRed(65535);
+    if (0xFFFF0000 & green()) setGreen(65535);
+    if (0xFFFF0000 & blue())  setBlue(65535);
+    if (0xFFFF0000 & alpha()) setAlpha(65535);
+}
+
+inline void DColor::blendClamp8()
+{
+    if (0xFF00 & red())   setRed(255);
+    if (0xFF00 & green()) setGreen(255);
+    if (0xFF00 & blue())  setBlue(255);
+    if (0xFF00 & alpha()) setAlpha(255);
+}
+
+} // namespace Digikam
+
+#endif  // DCOLORBLEND_H
+