1 // Copyright (c) 2006-2009 Nokia Corporation and/or its subsidiary(-ies).

     2 // All rights reserved.

     3 // This component and the accompanying materials are made available

     4 // under the terms of "Eclipse Public License v1.0"

     5 // which accompanies this distribution, and is available

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

     7 //

     8 // Initial Contributors:

     9 // Nokia Corporation - initial contribution.

    10 //

    11 // Contributors:

    12 //

    13 // Description:

    14 //

    15 

    16 #ifndef __LOOKUPTABLE_H__

    17 #define __LOOKUPTABLE_H__

    18 

    19 #include <e32std.h>

    20 

    21 /**

    22 @internalTechnology

    23 */

    24  IMPORT_C const TUint16* Convert16to32bppLow();

    25  IMPORT_C const TUint32* Convert16to32bppHigh();

    26 

    27 /**

    28 Returns the pointer to the table of 16-bit normalisation table.

    29 The table is currently used for performing un-multiplying Premultiplied Alpha color channels.

    30 Use: Let x be c * a/255, and y = c, then y = (x/a)*255, where a is in 0-255 range.

    31 		To use this table, use y = (x * Table[a])>>8. i.e, the inaccurate division is converted 

    32 		to more accurate multiplication and shift.

    33 		

    34 @return pointer to the normalisation table.

    35 @internalTechnology

    36 

    37 */

    38 IMPORT_C const TUint16* PtrTo16BitNormalisationTable();

    39 

    40 

    41 

    42 #endif