williamr@2: // Copyright (c) 2006-2009 Nokia Corporation and/or its subsidiary(-ies).
williamr@2: // All rights reserved.
williamr@2: // This component and the accompanying materials are made available
williamr@2: // under the terms of the License "Symbian Foundation License v1.0" to Symbian Foundation members and "Symbian Foundation End User License Agreement v1.0" to non-members
williamr@2: // which accompanies this distribution, and is available
williamr@2: // at the URL "http://www.symbianfoundation.org/legal/licencesv10.html".
williamr@2: //
williamr@2: // Initial Contributors:
williamr@2: // Nokia Corporation - initial contribution.
williamr@2: //
williamr@2: // Contributors:
williamr@2: //
williamr@2: // Description:
williamr@2: //
williamr@2: 
williamr@2: #ifndef __LOOKUPTABLE_H__
williamr@2: #define __LOOKUPTABLE_H__
williamr@2: 
williamr@2: #include <e32std.h>
williamr@2: 
williamr@2: /**
williamr@2: @internalTechnology
williamr@2: */
williamr@2:  IMPORT_C const TUint16* Convert16to32bppLow();
williamr@2:  IMPORT_C const TUint32* Convert16to32bppHigh();
williamr@2: 
williamr@2: /**
williamr@2: Returns the pointer to the table of 16-bit normalisation table.
williamr@2: The table is currently used for performing un-multiplying Premultiplied Alpha color channels.
williamr@2: Use: Let x be c * a/255, and y = c, then y = (x/a)*255, where a is in 0-255 range.
williamr@2: 		To use this table, use y = (x * Table[a])>>8. i.e, the inaccurate division is converted 
williamr@2: 		to more accurate multiplication and shift.
williamr@2: 		
williamr@2: @return pointer to the normalisation table.
williamr@2: @internalTechnology
williamr@2: 
williamr@2: */
williamr@2: IMPORT_C const TUint16* PtrTo16BitNormalisationTable();
williamr@2: 
williamr@2: 
williamr@2: 
williamr@2: #endif