sl@0: // Copyright (c) 2002-2009 Nokia Corporation and/or its subsidiary(-ies).
sl@0: // All rights reserved.
sl@0: // This component and the accompanying materials are made available
sl@0: // under the terms of "Eclipse Public License v1.0"
sl@0: // which accompanies this distribution, and is available
sl@0: // at the URL "http://www.eclipse.org/legal/epl-v10.html".
sl@0: //
sl@0: // Initial Contributors:
sl@0: // Nokia Corporation - initial contribution.
sl@0: //
sl@0: // Contributors:
sl@0: //
sl@0: // Description:
sl@0: // include\mmf\utils\rateconvert.h
sl@0: // 
sl@0: //
sl@0: 
sl@0: #ifndef RATECONVERT_H
sl@0: #define RATECONVERT_H
sl@0: 
sl@0: /**
sl@0: @internalTechnology
sl@0: @file
sl@0: */
sl@0: 
sl@0: #include <e32base.h>
sl@0: 
sl@0: /**
sl@0: Base utility class to change the sample rate of audio data in a buffer
sl@0: */
sl@0: class CChannelAndSampleRateConverter : public CBase
sl@0: 	{
sl@0: protected:
sl@0: 	CChannelAndSampleRateConverter();
sl@0: 	
sl@0: public:
sl@0: 	/*
sl@0: 	Create a converter that will do rate and channel conversion as requested
sl@0: 	*/
sl@0: 	IMPORT_C static CChannelAndSampleRateConverter* CreateL(TInt aFromRate,TInt aFromChannels,
sl@0: 												 TInt aToRate,TInt aToChannels);
sl@0: 	/**
sl@0: 	Reads the audio data from the source buffer,
sl@0: 	converts the number of channels and the sample rate
sl@0: 	and copies the result to the destination buffer
sl@0: 
sl@0: 	@param  aSrcBuffer
sl@0: 	        The source buffer containing the audio data to convert.
sl@0: 	@param  aDstBuffer
sl@0: 	        The destination buffer - assumed big enough
sl@0: 
sl@0: 	@return The length of the source buffer that was consumed.
sl@0: 	*/
sl@0: 	virtual TInt Convert(const TDesC8& aSrcBuffer, TDes8& aDstBuffer)=0;
sl@0: 	virtual void Reset()=0;
sl@0: 
sl@0: 	/*
sl@0: 	Indicates what buffer size is required to hold the converted data.
sl@0: 	Support size of original buffer. 
sl@0: 	aRoundUpToPower means give next power of 2 size up from raw size.
sl@0: 	NB. May be bigger than strictly necessary.
sl@0: 	*/
sl@0: 	virtual TInt MaxConvertBufferSize(TInt aSrcBufferSize, TBool aRoundUpToPower=EFalse)=0;
sl@0: 	};
sl@0: 
sl@0: 
sl@0: #endif
sl@0: