--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mmlibs/mmfw/Codecs/Src/MMFCodecCommon/MMFAudioPcm16ToImaAdpcmCodec.cpp	Tue Feb 02 01:56:55 2010 +0200
@@ -0,0 +1,165 @@
+// 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 "MMFAudioPcm16ToImaAdpcmCodec.h"
+
+
+EXPORT_C void TMMFAudioPcm16ToImaAdpcmCodec::SetState(const TMMFImaAdpcmCodecState& aState)
+	{
+     iState = aState ;
+	}
+
+EXPORT_C const TMMFImaAdpcmCodecState& TMMFAudioPcm16ToImaAdpcmCodec::GetState()
+	{
+	return iState;
+	}
+
+/**
+*
+* Convert
+* @param aSrc
+* @param aDst
+* @param aSamples
+*
+*/
+EXPORT_C void TMMFAudioPcm16ToImaAdpcmCodec::Convert(TUint8* aSrc, TUint8* aDst, TInt aSamples)
+	{
+	TInt val;			// Current input sample value 
+    TInt sign;			// Current adpcm sign bit 
+    TInt delta;			// Current adpcm output value 
+	TInt diff;			// Difference between val and valprev 
+	TInt step;			// Stepsize
+    TInt valpred;		// Predicted value 
+    TInt vpdiff;		// Current change to valpred 
+    TInt index;			// Current step change index 
+	
+	TInt16* srcPtr=REINTERPRET_CAST(TInt16*, aSrc);
+	TInt16* src=srcPtr;
+	
+	iState.iPredicted = *aSrc++;
+	iState.iPredicted |= STATIC_CAST(TInt16, ((*aSrc++) << 8));
+	
+    valpred = iState.iPredicted;
+    index = iState.iIndex;
+    ASSERT(index >= 0);
+    step = KStepSizeTable[index];
+	
+	//Write block header
+	*aDst++ = STATIC_CAST( TUint8, valpred);
+	*aDst++ = STATIC_CAST( TUint8, valpred >> 8);
+	*aDst++ = STATIC_CAST( TUint8, index);
+	*aDst++ = 0; //reserved byte
+	src++;
+	aSamples --;	
+	
+	for (; aSamples > 0; aSamples--) 
+		{ 
+		val = *src;
+		src++;
+		
+		step = KStepSizeTable[index];
+		
+		// Step 1 - compute difference with previous value 
+		diff = val - valpred;
+		sign = (diff < 0) ? 8 : 0;
+		if ( sign ) diff = (-diff);
+		
+		// Step 2 - Divide and clamp 
+		// Note:
+		// This code *approximately* computes:
+		//    delta = diff*4/step;
+		//    vpdiff = (delta+0.5)*step/4;
+		// but in shift step bits are dropped. The net result of this is
+		// that even if you have fast mul/div hardware you cannot put it to
+		// good use since the fixup would be too expensive.
+		//
+		delta = 0;
+		vpdiff = (step >> 3);
+		
+		if ( diff >= step ) 
+			{
+			delta = 4;
+			diff -= step;
+			vpdiff += step;
+			}
+		step >>= 1;
+		if ( diff >= step  ) 
+			{
+			delta |= 2;
+			diff -= step;
+			vpdiff += step;
+			}
+		step >>= 1;
+		if ( diff >= step ) 
+			{
+			delta |= 1;
+			vpdiff += step;
+			}
+		
+		// Step 3 - Update previous value 
+		if ( sign )
+			valpred -= vpdiff;
+		else
+			valpred += vpdiff;
+		
+		// Step 4 - Clamp previous value to 16 bits 
+		if ( valpred > KClamp - 1 )
+			valpred = KClamp - 1;
+		else if ( valpred < - KClamp )
+			valpred = - KClamp;
+		
+		// Step 5 - Assemble value, update index and step values 
+		delta |= sign;
+		
+		index += KIndexTable[delta];
+		if ( index < 0 ) index = 0;
+		if ( index > 88 ) index = 88;
+		
+		// Step 6 - Output value 
+		if (iBufferStep) 
+			iBuffer = delta & 0x0f;
+		else 
+			*aDst++ = STATIC_CAST( TInt8, ((delta << 4) & 0xf0) | iBuffer);
+		
+		iBufferStep = !iBufferStep;
+		}
+	
+	iState.iPredicted = STATIC_CAST(TInt16, valpred);
+	iState.iIndex = STATIC_CAST(TUint8, index);
+	}
+
+// IMA-ADPCM step variation table 
+const TInt TMMFAudioPcm16ToImaAdpcmCodec::KIndexTable[] =
+	{
+	-1, -1, -1, -1, 2, 4, 6, 8,
+	-1, -1, -1, -1, 2, 4, 6, 8
+	};
+	
+const TInt TMMFAudioPcm16ToImaAdpcmCodec::KStepSizeTable[] = 
+	{
+	7, 8, 9, 10, 11, 12, 13, 14, 16, 17,
+	19, 21, 23, 25, 28, 31, 34, 37, 41, 45,
+	50, 55, 60, 66, 73, 80, 88, 97, 107, 118,
+	130, 143, 157, 173, 190, 209, 230, 253, 279, 307,
+	337, 371, 408, 449, 494, 544, 598, 658, 724, 796,
+	876, 963, 1060, 1166, 1282, 1411, 1552, 1707, 1878, 2066,
+	2272, 2499, 2749, 3024, 3327, 3660, 4026, 4428, 4871, 5358,
+	5894, 6484, 7132, 7845, 8630, 9493, 10442, 11487, 12635, 13899,
+	15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794, 32767
+	};
+	
+
+
+