1 // Copyright (c) 2005-2009 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 #include "MmfBtPcm16ToAlawHwDevice.h"

    17 #include "../../MmfBtFileDependencyUtil.h"

    18 

    19 /**

    20 *

    21 * NewL

    22 *

    23 */

    24 CMMFPcm16ToAlawHwDevice* CMMFPcm16ToAlawHwDevice::NewL()

    25 	{

    26 	CMMFPcm16ToAlawHwDevice* self=new(ELeave) CMMFPcm16ToAlawHwDevice();

    27 	CleanupStack::PushL(self);

    28 	self->ConstructL();

    29 	CleanupStack::Pop(self);

    30 	return self;

    31 	}

    32 

    33 /**

    34 *

    35 * ~CMMFPcm16ToAlawHwDevice

    36 *

    37 */

    38 CMMFPcm16ToAlawHwDevice::~CMMFPcm16ToAlawHwDevice()

    39 	{

    40 	}

    41 

    42 /**

    43 *

    44 * ConstructL

    45 *

    46 */

    47 void CMMFPcm16ToAlawHwDevice::ConstructL()

    48 	{

    49 	iCodec = new (ELeave) CMMFPcm16ToALawCodec();

    50 	}

    51 

    52 

    53 /**

    54 *

    55 * Codec

    56 *

    57 */

    58 CMMFSwCodec &CMMFPcm16ToAlawHwDevice::Codec()

    59 	{

    60 	return *iCodec;

    61 	}

    62 

    63 /**

    64 *

    65 * ProcessL

    66 * @param aSrc

    67 * @param aDst

    68 * @pre position of buffer aSrc is 0

    69 * @pre position of buffer aDst is 0

    70 * @pre sufficient bytes in output to consume input

    71 * @return TCodecProcessResult

    72 *

    73 */

    74 CMMFSwCodec::TCodecProcessResult CMMFPcm16ToALawCodec::ProcessL(const CMMFBuffer& aSrc, CMMFBuffer& aDst)

    75 	{

    76 	CMMFSwCodec::TCodecProcessResult result;

    77 	result.iCodecProcessStatus = 	result.iCodecProcessStatus = TCodecProcessResult::EProcessComplete;

    78 	

    79 	//convert from generic CMMFBuffer to CMMFDataBuffer

    80 	const CMMFDataBuffer* src = STATIC_CAST(const CMMFDataBuffer*, &aSrc);

    81 	CMMFDataBuffer* dst = STATIC_CAST(CMMFDataBuffer*, &aDst);

    82 	

    83     if( !CheckPreconditions( src, dst ))

    84 		{

    85 		//[ precondition violation ]

    86 		User::Leave( KErrArgument );

    87 		}

    88 	

    89 	//we need to cast away CONST even on the source, as the TClass needs a TUint8*

    90 	TUint8* pSrc = CONST_CAST(TUint8*,src->Data().Ptr());

    91 	pSrc += src->Position();

    92 	TUint8* pDst = CONST_CAST(TUint8*,dst->Data().Ptr());

    93 	pDst += dst->Position();

    94 	

    95 	TUint destUse = src->Data().Length()/2;

    96 	

    97 	//compress TWO bytes (16-bit PCM word) into a to 1 byte sample

    98 	iPcm16ToALaw.Convert(pSrc, pDst, destUse );

    99 	

   100 	result.iCodecProcessStatus = TCodecProcessResult::EProcessComplete;

   101 	result.iSrcBytesProcessed  = src->Data().Length();

   102 	result.iDstBytesAdded      = destUse;

   103 	

   104 	dst->Data().SetLength(result.iDstBytesAdded);

   105 	

   106 	//[ post condition evaluation here ]

   107 	__ASSERT_DEBUG( (src->Position() == 0), TMmfAudioCodecPanicsNameSpace::Panic( 	TMmfAudioCodecPanicsNameSpace::EPostConditionViolation ));

   108 	__ASSERT_DEBUG( (dst->Position() == 0), TMmfAudioCodecPanicsNameSpace::Panic( 	TMmfAudioCodecPanicsNameSpace::EPostConditionViolation ));

   109 	__ASSERT_DEBUG( src->Data().Length()/2 == dst->Data().Length(), TMmfAudioCodecPanicsNameSpace::Panic( 	TMmfAudioCodecPanicsNameSpace::EPostConditionViolation ));

   110 		

   111 	return result;

   112 	}

   113 

   114 /**

   115 *

   116 * Preconditions

   117 * This methos tests the preconditions of the ProcessL method

   118 * @return TBool ETrue for sucess and EFalse for failure of the preconditions

   119 *

   120 **/

   121 TBool CMMFPcm16ToALawCodec::CheckPreconditions( const CMMFDataBuffer* aSrcBuffer, CMMFDataBuffer* aDestBuffer )

   122 	{

   123 	TBool result = EFalse;

   124 	

   125 	if(! aSrcBuffer )

   126 		{

   127 		return result;

   128 		}

   129 	

   130 	if( ! aDestBuffer )

   131 		{

   132 		return result;

   133 		}

   134 	

   135 	// Check position of src and dest are 0

   136 	if( aSrcBuffer->Position() )

   137 		{

   138 		return result;

   139 		}

   140 	

   141 	// Check position of src and dest are 0

   142 	if( aDestBuffer->Position() )

   143 		{

   144 		return result;

   145 		}

   146 	

   147 	// check there are sufficient bytes in the output to consume the input

   148 	if( ( aSrcBuffer->Data().Length()/2 > aDestBuffer->Data().MaxLength()) ||

   149 		( aSrcBuffer->Data().Length() % 2 != 0 ))

   150 		{

   151 		return result;

   152 		}

   153 	

   154 	result = ETrue;  // preconditions have been satisfied

   155 	

   156 	return result;

   157 	}