// 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\utils\rateconvert.h

 // 

 //

 #ifndef RATECONVERT_H

 #define RATECONVERT_H

 /**

 @internalTechnology

 @file

 */

 #include <e32base.h>

 /**

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

 */

 class CChannelAndSampleRateConverter : public CBase

 	{

 protected:

 	CChannelAndSampleRateConverter();

 public:

 	/*

 	Create a converter that will do rate and channel conversion as requested

 	*/

 	IMPORT_C static CChannelAndSampleRateConverter* CreateL(TInt aFromRate,TInt aFromChannels,

 												 TInt aToRate,TInt aToChannels);

 	/**

 	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

 	        The source buffer containing the audio data to convert.

 	@param  aDstBuffer

 	        The destination buffer - assumed big enough

 	@return The length of the source buffer that was consumed.

 	*/

 	virtual TInt Convert(const TDesC8& aSrcBuffer, TDes8& aDstBuffer)=0;

 	virtual void Reset()=0;

 	/*

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

 	Support size of original buffer. 

 	aRoundUpToPower means give next power of 2 size up from raw size.

 	NB. May be bigger than strictly necessary.

 	*/

 	virtual TInt MaxConvertBufferSize(TInt aSrcBufferSize, TBool aRoundUpToPower=EFalse)=0;

 	};

 #endif