// Copyright (c) 1997-2009 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 "MMFCodecBaseDefinitions.h"

#include "MMFAudioCodecBase.h"

#include <mmf/common/mmfpaniccodes.h>

// Base of Audio codecs

// These T Classes are "wrapped" by derived MMFCodecs, not exposed directly.

void Panic(TInt aPanicCode)

	{

	_LIT(KMMFCodecBaseDefinitionsPanicCategory, "MMFCodecBaseDefinitions");

	User::Panic(KMMFCodecBaseDefinitionsPanicCategory, aPanicCode);

	}

void TMMFImaAdpcmBaseCodecOld::ResetBuffer()

	{

	iBufferStep = ETrue;

	iBuffer = 0;

	}

TBool TMMFImaAdpcmBaseCodecOld::OutputStep()

	{

	return !iBufferStep;

	}

void TMMFImaAdpcmTo16PcmCodecOld::Convert(TUint8* aSrc, TUint8* aDst, TInt aSamples)

	{

    TInt delta;			// Current adpcm output value 

    TInt step;			// Stepsize

    TInt valpred;		// Predicted value 

    TInt vpdiff;		// Current change to valpred 

    TInt index;			// Current step change index 

	TInt channelCount=16;//for stereo only

	aSamples*=iChannels;

	//Read first sample and index from block header

	iState[0].iPredicted = *aSrc++;

	iState[0].iPredicted |= STATIC_CAST(TInt16, ((*aSrc++) << 8));

	iState[0].iIndex = *aSrc++;

	aSrc++; //skip reserved header byte

	valpred = iState[0].iPredicted;

	index = iState[0].iIndex;

	TUint8* dst=aDst;

	//Write first sample to dest

	*aDst++ = STATIC_CAST( TUint8, valpred);

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

	dst += 2;

	aSamples --;

	if (iChannels==2)

		{

		iState[1].iPredicted = *aSrc++;

		iState[1].iPredicted |= STATIC_CAST(TInt16, ((*aSrc++) << 8));

		iState[1].iIndex = *aSrc++;

		aSrc++;

		*aDst++ = STATIC_CAST( TUint8, iState[1].iPredicted);

		*aDst++ = STATIC_CAST( TUint8, iState[1].iPredicted >> 8);

		dst += 2;

		aSamples --;

		}

    for ( ; aSamples > 0 ; aSamples-- ) 

		{ 

		// Step 1 - get the delta value

		if (iBufferStep) 

			{

			iBuffer = *aSrc++;

			delta = iBuffer & 0xf;

			} 

		else 

			{

			delta = (iBuffer >> 4) & 0xf;

			}

		iBufferStep = !iBufferStep;

		ASSERT(index >= 0);

		step = iStepSizeTable[index];

		vpdiff = step>>3;

		if ( delta & 4 ) 

			vpdiff += step;

		if ( delta & 2 ) 

			vpdiff += step>>1;

		if ( delta & 1 ) 

			vpdiff += step>>2;

		if ( delta & 8 )

			valpred -= vpdiff;

		else

			valpred += vpdiff;

		if ( valpred > (KClamp - 1) )

			valpred = (KClamp - 1);

		else if ( valpred < -KClamp )

			valpred = -KClamp;

		index += iIndexTable[delta];

		if ( index < 0 ) 

			index = 0;

		if ( index > KMaxImaAdpcmTableEntries ) 

			index = KMaxImaAdpcmTableEntries;

		*dst++ = STATIC_CAST( TUint8, valpred&KAndMask8bit);

		*dst++ = STATIC_CAST( TUint8, (valpred>>8)&KAndMask8bit);

		if (iChannels==2)

			{

			dst+=2;

			if (--channelCount == 8)

				{

				dst=aDst+2;	//right channel

				iState[0].iPredicted=STATIC_CAST(TInt16, valpred);

				iState[0].iIndex=STATIC_CAST(TUint8,index);

				valpred = iState[1].iPredicted;

				index = iState[1].iIndex;

				}

			else

				{

				if (!channelCount)

					{

					aDst+=32;

					dst=aDst;

					channelCount=16;

					iState[1].iPredicted=STATIC_CAST(TInt16, valpred);

					iState[1].iIndex=STATIC_CAST(TUint8, index);

					valpred = iState[0].iPredicted;

					index = iState[0].iIndex;

					}

				}

			}

		}

	if (iChannels==1)

		{

		iState[0].iPredicted=STATIC_CAST(TInt16,valpred);

		iState[0].iIndex=STATIC_CAST(TUint8,index);

		}

	}

void TMMF16PcmToImaAdpcmCodecOld::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;

	TInt bufferCount=16;//for stereo only

	if (iChannels==2)

		{

		aSamples*=2;

		iBufferStep=ETrue;

		}

	iState[0].iPredicted = *aSrc++;

	iState[0].iPredicted |= STATIC_CAST(TInt16, ((*aSrc++) << 8));

    valpred = iState[0].iPredicted;

    index = iState[0].iIndex;

    ASSERT(index >= 0);

    step = iStepSizeTable[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 --;	

	if (iChannels==2)

		{

		iState[1].iPredicted = *aSrc++;

		iState[1].iPredicted |= STATIC_CAST(TInt16, ((*aSrc++) << 8));

		//Write header for second channel

		*aDst++ = STATIC_CAST( TUint8, iState[1].iPredicted);

		*aDst++ = STATIC_CAST( TUint8, iState[1].iPredicted >> 8);

		*aDst++ = STATIC_CAST( TUint8, iState[1].iIndex);

		*aDst++ = 0;

		src ++;

		aSamples --;

		}

	for (; aSamples > 0; aSamples--) 

		{ 

		val = *src;

		src += iChannels;

		ASSERT(index >= 0);

	    step = iStepSizeTable[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 += iIndexTable[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;

		if (iChannels==2)

			{

			if (--bufferCount==8)

				{

				src=srcPtr+1;	//right channel

				iState[0].iPredicted = STATIC_CAST(TInt16, valpred);

				iState[0].iIndex = STATIC_CAST(TUint8, index);

				valpred = iState[1].iPredicted;

				index = iState[1].iIndex;

				}

			else

				{

				if (!bufferCount)

					{

					iState[1].iPredicted = STATIC_CAST(TInt16, valpred);

					iState[1].iIndex = STATIC_CAST(TUint8, index);

					valpred = iState[0].iPredicted;

					index = iState[0].iIndex;

					bufferCount=16;

					srcPtr+=16;//32bytes

					src=srcPtr;

					}

				}

			}

		}

	if (iChannels==1)

		{

		iState[0].iPredicted = STATIC_CAST(TInt16, valpred);

		iState[0].iIndex = STATIC_CAST(TUint8, index);

		}

	}

// IMA-ADPCM step variation table 

const TInt TMMFImaAdpcmBaseCodecOld::iIndexTable[16] =

 	{

    -1, -1, -1, -1, 2, 4, 6, 8,

    -1, -1, -1, -1, 2, 4, 6, 8

	};

const TInt TMMFImaAdpcmBaseCodecOld::iStepSizeTable[89] = 

	{

    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

	};