// Copyright (c) 2002-2009 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\mmf\common\mmfutilities.h

// 

//

#ifndef __MMF_COMMON_HELPER_H__

#define __MMF_COMMON_HELPER_H__

#include <e32base.h>

#include <mmf/server/mmfdatabuffer.h>

#include <mmf/common/mmffourcc.h>

/**

@internalAll

Base utility class to change the sample rate of audio data in a buffer

*/

class CMMFChannelAndSampleRateConverter : public CBase

	{

public:

	/**

	Reads the audio data from the source buffer,

	converts the number of channels and the sample rate

	and copies the result to the destination buffer

	@param  aSrcBuffer

	        A pointer to a source buffer containing the audio data to convert.

	@param  aDstBuffer

	        A pointer to a destination buffer.

	@return The length of the destination buffer.

	*/

	virtual TInt Convert(const CMMFDataBuffer& aSrcBuffer, CMMFDataBuffer& aDstBuffer) =0;

	virtual void Reset() {};

	/*

	Indicates what buffer size is required to hold the converted data.

	*/

	virtual TUint MaxConvertBufferSize(TUint aSrcBufferSize) {return aSrcBufferSize;}

	void SetRates(TInt aSrcRate,TInt aSrcChannels,TInt aDstRate,TInt aDstChannels);

public:

	/*

	The sample rate of the data in the source buffer

	*/

	TInt iFromRate;

	/*

	The sample rate of the data in the destination buffer

	*/

	TInt iToRate;

	/*

	The number of channels of data in the source buffer

	*/

	TInt iFromChannels;

	/*

	The number of channels of data in the destination buffer

	*/

	TInt iToChannels;

protected:

	TReal iRatio;

	TInt iFraction;

	TInt iIndex;

	};

/**

@internalAll

*/

class CMMFStereoToMonoRateConverter : public CMMFChannelAndSampleRateConverter

	{

	public:

		virtual TInt Convert(const CMMFDataBuffer& aSrcBuffer, CMMFDataBuffer& aDstBuffer);

		virtual TUint MaxConvertBufferSize(TUint aSrcBufferSize);

	};

/**

@internalAll

*/

class CMMFStereoToMonoConverter : public CMMFChannelAndSampleRateConverter

	{

	public:

		virtual TInt Convert(const CMMFDataBuffer& aSrcBuffer, CMMFDataBuffer& aDstBuffer);

		virtual TUint MaxConvertBufferSize(TUint aSrcBufferSize);

	};

/**

@internalAll

*/

class CMMFStereoToStereoRateConverter : public CMMFChannelAndSampleRateConverter

	{

	public:

		virtual TInt Convert(const CMMFDataBuffer& aSrcBuffer, CMMFDataBuffer& aDstBuffer);

	};

/**

@internalAll

*/

class CMMFMonoToMonoRateConverter : public CMMFChannelAndSampleRateConverter

	{

	public:

		virtual TInt Convert(const CMMFDataBuffer& aSrcBuffer, CMMFDataBuffer& aDstBuffer);

	};

/**

@internalAll

*/

class CMMFMonoToStereoConverter : public CMMFChannelAndSampleRateConverter

	{

	public:

		virtual TInt Convert(const CMMFDataBuffer& aSrcBuffer, CMMFDataBuffer& aDstBuffer);

		virtual TUint MaxConvertBufferSize(TUint aSrcBufferSize);

	};

/**

@internalAll

*/

class CMMFMonoToStereoRateConverter : public CMMFChannelAndSampleRateConverter

	{

	public:

		virtual TInt Convert(const CMMFDataBuffer& aSrcBuffer, CMMFDataBuffer& aDstBuffer);

		virtual TUint MaxConvertBufferSize(TUint aSrcBufferSize);

	};

/**

@internalAll

Factory class to create the appropriate CMMFChannelAndSampleRateConverter-derived

class depending on the supplied number of channels and bit rate

*/

class CMMFChannelAndSampleRateConverterFactory : public CBase

	{

public:

	IMPORT_C CMMFChannelAndSampleRateConverter* CreateConverterL(TInt aFromRate,TInt aFromChannels,

												 TInt aToRate,TInt aToChannels);

	IMPORT_C CMMFChannelAndSampleRateConverter* CreateConverterL();

	CMMFChannelAndSampleRateConverter* Converter() {return iConverter;}

	IMPORT_C ~CMMFChannelAndSampleRateConverterFactory();

	TInt Rate() {return iToRate;}

	TInt Channels() {return iToChannels;}

public:

	/**

	The sample rate of the data in the source buffer

	*/

	TInt iFromRate;

	/**

	The sample rate of the data in the destination buffer

	*/

	TInt iToRate;

	/**

	The number of channels of data in the source buffer

	*/

	TInt iFromChannels;

	/**

	The number of channels of data in the destination buffer

	*/

	TInt iToChannels;

private:

	CMMFChannelAndSampleRateConverter* iConverter;

	};

#endif //__MMF_COMMON_HELPER_H__