author | William Roberts <williamr@symbian.org> |
Tue, 16 Mar 2010 16:12:26 +0000 | |
branch | Symbian2 |
changeset 2 | 2fe1408b6811 |
permissions | -rw-r--r-- |
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// Copyright (c) 2006-2009 Nokia Corporation and/or its subsidiary(-ies). |
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// All rights reserved. |
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// This component and the accompanying materials are made available |
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// 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 |
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// which accompanies this distribution, and is available |
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// at the URL "http://www.symbianfoundation.org/legal/licencesv10.html". |
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// |
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// Initial Contributors: |
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// Nokia Corporation - initial contribution. |
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// |
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// Contributors: |
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// |
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// Description: |
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// |
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|
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#ifndef __LOOKUPTABLE_H__ |
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#define __LOOKUPTABLE_H__ |
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|
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#include <e32std.h> |
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|
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/** |
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@internalTechnology |
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*/ |
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IMPORT_C const TUint16* Convert16to32bppLow(); |
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IMPORT_C const TUint32* Convert16to32bppHigh(); |
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|
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/** |
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Returns the pointer to the table of 16-bit normalisation table. |
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The table is currently used for performing un-multiplying Premultiplied Alpha color channels. |
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Use: Let x be c * a/255, and y = c, then y = (x/a)*255, where a is in 0-255 range. |
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To use this table, use y = (x * Table[a])>>8. i.e, the inaccurate division is converted |
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to more accurate multiplication and shift. |
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|
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@return pointer to the normalisation table. |
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@internalTechnology |
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|
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*/ |
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IMPORT_C const TUint16* PtrTo16BitNormalisationTable(); |
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#endif |