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".
8 // Initial Contributors:
9 // Nokia Corporation - initial contribution.
16 #ifndef __LOOKUPTABLE_H__
17 #define __LOOKUPTABLE_H__
24 IMPORT_C const TUint16* Convert16to32bppLow();
25 IMPORT_C const TUint32* Convert16to32bppHigh();
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.
34 @return pointer to the normalisation table.
38 IMPORT_C const TUint16* PtrTo16BitNormalisationTable();