os/mm/mmlibs/mmfw/src/Plugin/Codec/audio/Mmfpcm16Tomulawcodec.cpp
author sl@SLION-WIN7.fritz.box
Fri, 15 Jun 2012 03:10:57 +0200
changeset 0 bde4ae8d615e
permissions -rw-r--r--
First public contribution.
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// Copyright (c) 1997-2009 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 "Eclipse Public License v1.0"
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// which accompanies this distribution, and is available
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// at the URL "http://www.eclipse.org/legal/epl-v10.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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#include "MMFPcm16ToMuLawCodec.h"
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// __________________________________________________________________________
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// Implementation
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CMMFCodec* CMMFPcm16MulawCodec::NewL(TAny* aInitParams)
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	{
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	CMMFPcm16MulawCodec* self=new(ELeave) CMMFPcm16MulawCodec();
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	CleanupStack::PushL(self);
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	self->ConstructL(aInitParams);
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	CleanupStack::Pop(self);
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	return STATIC_CAST( CMMFCodec*, self );
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	}
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CMMFPcm16MulawCodec::~CMMFPcm16MulawCodec()
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	{
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	}
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CMMFPcm16MulawCodec::CMMFPcm16MulawCodec()
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	{
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	}
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void CMMFPcm16MulawCodec::ConstructL(TAny*  /*aInitParams*/)
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	{
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	}
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//this codec converts 2 bytes into 1
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TCodecProcessResult CMMFPcm16MulawCodec::ProcessL(const CMMFBuffer& aSrc, CMMFBuffer& aDst)
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	{
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	TCodecProcessResult result;
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	result.iStatus = TCodecProcessResult::EProcessIncomplete;
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	//convert from generic CMMFBuffer to CMMFDataBuffer
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	iSrc = STATIC_CAST(const CMMFDataBuffer*, &aSrc);
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	iDst = STATIC_CAST(CMMFDataBuffer*, &aDst);
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	const TUint dstMaxLen = iDst->Data().MaxLength();
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	if (!dstMaxLen)
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		User::Leave(KErrArgument);
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	//don't scribble Destination (pDst) by only consuming enough source to fill pDst
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	TUint srcUse = (dstMaxLen - iDst->Position()) * 2;
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	const TUint srcLen = iSrc->Data().Length();
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	const TUint sourceRemain = srcLen - iSrc->Position();
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	//make sure we don't blow source by checking against remaining
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	//and clipping to minimum remaining if necessary
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	srcUse = (srcUse<sourceRemain ? srcUse : sourceRemain);
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	//we need to cast away CONST even on the source, as the TClass needs a TUint8*
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	TUint8* pSrc = CONST_CAST(TUint8*,iSrc->Data().Ptr());
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	pSrc += iSrc->Position();
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	TUint8* pDst = CONST_CAST(TUint8*,iDst->Data().Ptr());
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	pDst += iDst->Position();
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	//compress TWO bytes (16-bit PCM word) into a to 1 byte sample
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	i16PcmToMulaw.Convert(pSrc, pDst, srcUse / 2);
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	TUint dstBytesAdded = srcUse / 2;
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	if (dstBytesAdded + iDst->Position() < dstMaxLen)
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		result.iStatus = TCodecProcessResult::EDstNotFilled;
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	else if (srcUse + iSrc->Position() >= srcLen)
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		result.iStatus = TCodecProcessResult::EProcessComplete;
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	result.iSrcBytesProcessed = srcUse;
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	result.iDstBytesAdded = dstBytesAdded;
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	iDst->Data().SetLength(iDst->Position() + result.iDstBytesAdded);
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	return result;
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	}