--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/vtprotocolplugins/DisplaySink/inc/CVtImageScalerImpl.h	Mon Nov 23 14:47:47 2009 +0200
@@ -0,0 +1,151 @@
+/*
+* Copyright (c) 2004 Nokia Corporation and/or its subsidiary(-ies).
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of "Eclipse Public License v1.0"
+* which accompanies this distribution, and is available
+* at the URL "http://www.eclipse.org/legal/epl-v10.html".
+*
+* Initial Contributors:
+* Nokia Corporation - initial contribution.
+*
+* Contributors:
+*
+* Description:    Image Transforms subsystem.
+*
+*/
+
+
+
+
+#ifndef CVTIMAGESCALERIMPL_H
+#define CVTIMAGESCALERIMPL_H
+
+// INCLUDE FILES
+
+#include <e32base.h>
+#include <bitmaptransforms.h>
+
+// FORWARD DECLARATIONS
+
+class CVtImage;
+
+// CLASS DECLARATIONS
+
+/**
+*  Image scaler implementation.
+*
+*  @lib videosource.lib
+*/
+class CVtImageScalerImpl : public CActive
+    {
+    protected:
+
+        /**
+         * Constructor.
+         */
+        CVtImageScalerImpl();
+
+    public:
+
+        /**
+         * Destructor.
+         */
+        ~CVtImageScalerImpl();
+
+        /**
+        * Sets scaler params.
+        * @param "aParams" Scaling params, including source and target images.
+        * @exception In error situation leaves with one of the system wide
+        * error codes.
+        */
+        void SetSourceTargetL( const CVtImage& aSource, CVtImage& aTarget );
+
+        /**
+        * Method to check whether bitmap heap locking is needed or not during
+        * scaling process.
+        * @exception In error situation leaves with one of the system wide
+        * error codes.
+        * @return ETrue if bitmap heap lock is needed, EFalse otherwise.
+        */
+        TBool NeedHeapLock() const;
+
+        /**
+        * Pure virtual scaling method.
+        * @param "aContinue" When method returns, this parameter will contain
+        * ETrue if new call is needed (i.e. scaling is not yet finished) or
+        * EFalse if scaling is complete.
+        * @return KErrNone or one of the system wide error codes.
+        */
+        virtual TInt Scale( TBool& aContinue ) = 0;
+
+    protected:
+
+        /**
+         * Scales using CBitmapScaler, which is slow but works with any
+         * Symbian color mode.
+         * @param aQuality Scaling quality @see CBitmapScaler::TQualityAlgorithm
+         * @exception In error situation leaves with one of the system wide
+         * error codes.
+         */
+        void ScaleWithBitmapScalerL(
+            const CBitmapScaler::TQualityAlgorithm aQuality );
+
+    private:
+
+        /**
+        * Pure virtual source and target image validation method.
+        * @param "aSource" Constant reference to source image.
+        * @param "aTarget" Constant reference to target image.
+        * @exception If source or target is not valid, this method leaves
+        * with KErrNotSupported.
+        */
+        virtual void ValidateSourceTargetL(
+            const CVtImage& aSource,
+            CVtImage& aTarget ) = 0;
+
+        /**
+        * Method for validating image size.
+        * @param "aSize" Size to be validated.
+        * @param "aMinSize" Minimum allowed size. If this is not given a default
+        * size of TSize( 1, 1 ) is used.
+        * @exception If size is not valid within given parameters, this
+        * method leaves with KErrNotSupported.
+        */
+        void LeaveIfNotValidSizeL(
+            const TSize& aSize,
+            const TSize aMinSize = TSize( 1, 1 ) );
+
+    private: // from CActive
+
+        /**
+         * @see CActive::RunL
+         */
+        void RunL();
+
+        /**
+         * @see CActive::DoCancel
+         */
+        void DoCancel();
+
+    protected:
+
+        // Source for scaling
+        const CVtImage* iSource; // not owned
+
+        // Target image (will hold scaled source)
+        CVtImage* iTarget; // not owned
+
+        // Bitmap scaler instance
+        CBitmapScaler* iScaler;
+
+        // Active scheduler waiter object
+        CActiveSchedulerWait iActiveSchedulerWait;
+
+    };
+
+#endif // CVTIMAGESCALERIMPL_H
+
+// End of File
+
+