1 // Copyright (c) 1997-2009 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 "MMFPcm16ToMuLawCodec.h"

    17 

    18 

    19 // __________________________________________________________________________

    20 // Implementation

    21 

    22 CMMFCodec* CMMFPcm16MulawCodec::NewL(TAny* aInitParams)

    23 	{

    24 	CMMFPcm16MulawCodec* self=new(ELeave) CMMFPcm16MulawCodec();

    25 	CleanupStack::PushL(self);

    26 	self->ConstructL(aInitParams);

    27 	CleanupStack::Pop(self);

    28 	return STATIC_CAST( CMMFCodec*, self );

    29 	}

    30 

    31 CMMFPcm16MulawCodec::~CMMFPcm16MulawCodec()

    32 	{

    33 	}

    34 

    35 CMMFPcm16MulawCodec::CMMFPcm16MulawCodec()

    36 	{

    37 	}

    38 

    39 void CMMFPcm16MulawCodec::ConstructL(TAny*  /*aInitParams*/)

    40 	{

    41 	}

    42 

    43 

    44 //this codec converts 2 bytes into 1

    45 TCodecProcessResult CMMFPcm16MulawCodec::ProcessL(const CMMFBuffer& aSrc, CMMFBuffer& aDst)

    46 	{

    47 

    48 	TCodecProcessResult result;

    49 	result.iStatus = TCodecProcessResult::EProcessIncomplete;

    50 

    51 	//convert from generic CMMFBuffer to CMMFDataBuffer

    52 	iSrc = STATIC_CAST(const CMMFDataBuffer*, &aSrc);

    53 	iDst = STATIC_CAST(CMMFDataBuffer*, &aDst);

    54 

    55 	const TUint dstMaxLen = iDst->Data().MaxLength();

    56 

    57 	if (!dstMaxLen)

    58 		User::Leave(KErrArgument);

    59 

    60 	//don't scribble Destination (pDst) by only consuming enough source to fill pDst

    61 	TUint srcUse = (dstMaxLen - iDst->Position()) * 2;

    62 	const TUint srcLen = iSrc->Data().Length();

    63 	const TUint sourceRemain = srcLen - iSrc->Position();

    64 

    65 	//make sure we don't blow source by checking against remaining

    66 	//and clipping to minimum remaining if necessary

    67 	srcUse = (srcUse<sourceRemain ? srcUse : sourceRemain);

    68 

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

    70 	TUint8* pSrc = CONST_CAST(TUint8*,iSrc->Data().Ptr());

    71 	pSrc += iSrc->Position();

    72 	TUint8* pDst = CONST_CAST(TUint8*,iDst->Data().Ptr());

    73 	pDst += iDst->Position();

    74 

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

    76 	i16PcmToMulaw.Convert(pSrc, pDst, srcUse / 2);

    77 

    78 	TUint dstBytesAdded = srcUse / 2;

    79 

    80 	if (dstBytesAdded + iDst->Position() < dstMaxLen)

    81 		result.iStatus = TCodecProcessResult::EDstNotFilled;

    82 

    83 	else if (srcUse + iSrc->Position() >= srcLen)

    84 		result.iStatus = TCodecProcessResult::EProcessComplete;

    85 

    86 	result.iSrcBytesProcessed = srcUse;

    87 	result.iDstBytesAdded = dstBytesAdded;

    88 

    89 	iDst->Data().SetLength(iDst->Position() + result.iDstBytesAdded);

    90 

    91 	return result;

    92 

    93 	}