// Copyright (c) 2003-2009 Nokia Corporation and/or its subsidiary(-ies).

 // All rights reserved.

 // This component and the accompanying materials are made available

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

 // which accompanies this distribution, and is available

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

 //

 // Initial Contributors:

 // Nokia Corporation - initial contribution.

 //

 // Contributors:

 //

 // Description:

 //

 #include "MMFAudioALawToS16PcmCodec.h"

 /***

 *

 * Convert

 *

 */

 EXPORT_C void TMMFAudioALawToS16PcmCodec::Convert(TUint8* aSrc, TUint8* aDst, TInt aSamples)

 	{

 	ASSERT(aSrc);

 	ASSERT(aDst);

 	TInt pcm;

 	while (aSamples--)

 		{

 		pcm = AlawSampleToPcm(*aSrc++);

 		*aDst++ = STATIC_CAST( TUint8, pcm&KAndMask8bit);

 		*aDst++ = STATIC_CAST( TUint8, pcm>>8);

 		}

 	}

 /***

 *

 * AlawSampleToPcm

 * @param aLaw

 * @return TInt

 *

 */

 TInt TMMFAudioALawToS16PcmCodec::AlawSampleToPcm(TUint8 aAlaw)

 	{

     TInt sign, exponent, mantissa, sample;

     aAlaw ^= 0x55;	//will leave this as is, more readable

     sign = ( aAlaw & KMaskSign8bit );

     aAlaw &= 0x7f;			/* get magnitude */

     if (aAlaw >= 16)

 		{

 		exponent = (aAlaw >> 4 ) & 0x07;

 		mantissa = aAlaw & 0x0F;

 		sample = KExpLut[exponent] + ( mantissa << ( exponent + 3 ) );

 		}

     else

 		sample = (aAlaw << 4) + 8;

     if ( sign == 0 )

 		sample = -sample;

     return sample;

 	}

 const TInt TMMFAudioALawToS16PcmCodec::KExpLut[] = 

 	{

 	0, 264, 528, 1056, 2112, 4224, 8448, 16896

 	};