1 /*

     2 * Copyright (c) 2008 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description:  Downscales images when necessary

    15  *

    16 */

    17 

    18 

    19 #ifndef CPIMIMAGESCALER_H

    20 #define CPIMIMAGESCALER_H

    21 

    22 //  INCLUDES

    23 #include <e32base.h>

    24 #include <imageconversion.h>

    25 #include <bitmaptransforms.h>

    26 

    27 // CONSTANTS

    28 const TInt KThumbHeight = 96;

    29 const TInt KThumbWidth = 80;

    30 const TInt KMaxJpegSize = 23296; // 80*96*3+256

    31 

    32 // CLASS DECLARATION

    33 

    34 /**

    35  *  Scales bitmaps when necessary.

    36  *  The purpose of this class is to resize given bitmaps to thumbnail size

    37  * (80x96). If the given image is already smaller than 80x96, it is not scaled.

    38  *

    39  */

    40 NONSHARABLE_CLASS(CPIMImageScaler): public CActive

    41 {

    42 public: // type definitions

    43     enum TState

    44     {

    45         EReady,

    46         EOpening,

    47         EScaling,

    48         EEncoding,

    49         ECompleted,

    50         // Error state

    51         EError

    52     };

    53 

    54 public: // Constructors and destructor

    55 

    56     /**

    57      * Two-phased constructor.

    58      */

    59     static CPIMImageScaler* NewL();

    60 

    61     /**

    62      * Destructor.

    63      */

    64     virtual ~CPIMImageScaler();

    65 

    66 public: // New functions

    67 

    68     /**

    69      * Scales the bitmap to thumbnail size (80x96) if necessary.

    70      * The image is not scaled, if it already is smaller than necessary.

    71      *

    72      * @param aSrcImage Source image.

    73      * @return thumbnail sized full color JPEG as a descriptor. Caller takes

    74      * the ownership.

    75      */

    76     HBufC8* ScaleL(TDesC8& aSrcImage);

    77 

    78 public: // CActive

    79     void RunL();

    80     void DoCancel();

    81 

    82 private:

    83 

    84     /**

    85      * C++ default constructor.

    86      */

    87     CPIMImageScaler();

    88 

    89     /**

    90      * Second phase constructor

    91      */

    92     void ConstructL();

    93 

    94     /**

    95      * Completes the operation

    96      * @param aError Error status or KErrNone if no error

    97      */

    98     void Complete(TInt aError);

    99 

   100     /**

   101      * Checks the given size. If the size is larger than required,

   102      * returns true

   103      */

   104     TBool CheckSize(TSize aSize);

   105 

   106     /**

   107      * Encodes the image

   108      */

   109     void Encode();

   110 

   111 private: // Data

   112 

   113     // Opens JPEG images from a descriptor, owned

   114     CImageDecoder* iImageReader;

   115 

   116     // Converts bitmap to a JPEG image, owned

   117     CImageEncoder* iImageWriter;

   118 

   119     // Scales bitmaps,owned

   120     CBitmapScaler* iBitmapScaler;

   121 

   122     // Holds the encoded image. Owned while processing the image

   123     // when the image is returned, this pointer is changed to NULL.

   124     HBufC8* iImage;

   125 

   126     // Holds the bitmap. Owned.

   127     CFbsBitmap* iBitmap;

   128 

   129     // Waits for the operation to complete. Owned.

   130     CActiveSchedulerWait* iWait;

   131 

   132     // Current state

   133     TState iState;

   134 

   135     // Error code, propagated upwards on error

   136     TInt iError;

   137 

   138     // Do we have a connection to Font and Bitmap Server

   139     TBool iFbsSessionConnected;

   140 

   141     RFs iFileServer;

   142 

   143 };

   144 

   145 #endif // CPIMIMAGESCALER_H

   146 // End of File