diff -r 5dc02b23752f -r 3e2da88830cd src/gui/image/qimage_p.h
--- a/src/gui/image/qimage_p.h	Tue Jul 06 15:10:48 2010 +0300
+++ b/src/gui/image/qimage_p.h	Wed Aug 18 10:37:55 2010 +0300
@@ -63,6 +63,8 @@
 
 QT_BEGIN_NAMESPACE
 
+class QImageWriter;
+
 struct Q_GUI_EXPORT QImageData {        // internal image data
     QImageData();
     ~QImageData();
@@ -96,6 +98,9 @@
 
     bool checkForAlphaPixels() const;
 
+    // Convert the image in-place, minimizing memory reallocation
+    // Return false if the conversion cannot be done in-place.
+    bool convertInPlace(QImage::Format newFormat, Qt::ImageConversionFlags);
 
 #ifndef QT_NO_IMAGE_TEXT
     QMap<QString, QString> text;
@@ -105,6 +110,8 @@
     QPaintEngine *paintEngine;
 };
 
+void qInitImageConversions();
+
 QT_END_NAMESPACE
 
 #endif