/*

* Copyright (c) 2006 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:    PayloadFormat plugin capable to read RTP payload containing

*                Amr audio.

*

*/

// INCLUDE FILES

#include "amrpayloadheader.h"

#include "streamformatter.h"

// CONSTANTS

// ============================= LOCAL FUNCTIONS ===============================

// ============================ MEMBER FUNCTIONS ===============================

// ---------------------------------------------------------------------------

// CAmrPayloadHeader::CAmrPayloadHeader

// C++ default constructor can NOT contain any code, that

// might leave.

// ---------------------------------------------------------------------------

//

CAmrPayloadHeader::CAmrPayloadHeader() :iCmr( EAmrModeReqNone )

    {

    DP_AMR_ENCODE( "CAmrPayloadHeader::CAmrPayloadHeader" );        

    }

// ---------------------------------------------------------------------------

// CAmrPayloadHeader::NewL

// Two-phased constructor.

// ---------------------------------------------------------------------------

//

CAmrPayloadHeader* CAmrPayloadHeader::NewL()

    {

    DP_AMR_ENCODE( "CAmrPayloadHeader::NewL" );

    CAmrPayloadHeader* self = new( ELeave ) CAmrPayloadHeader( );

    return self;

    }

// Destructor

CAmrPayloadHeader::~CAmrPayloadHeader()

    {

    DP_AMR_ENCODE( "CAmrPayloadHeader::~CAmrPayloadHeader" );

    }

// ---------------------------------------------------------------------------

// CAmrPayloadHeader::Encode

// Encode the payload header fields into a given buffer at the given position.

// ---------------------------------------------------------------------------

//

void CAmrPayloadHeader::Encode( TUint8* aBuffer,

        TInt& aByteIndex, TInt& aBitIndex )

    {

    DP_AMR_ENCODE( "CAmrPayloadHeader::Encode" );

    TStreamEncoder encoder;

    encoder.Initialize( aBuffer, aByteIndex, aBitIndex );

    //In bandwidth-efficient mode, the payload header simply consists of a

    //4 bit codec mode request:

    //  0 1 2 3

    // +-+-+-+-+

    // |  CMR  |

    // +-+-+-+-+

    encoder.Encode( iCmr, KCMRFieldBits );

    // Update Byte and Bit positions

    aByteIndex = encoder.ByteIndex( ); 

    aBitIndex = encoder.BitIndex( );

    }

// ---------------------------------------------------------------------------

// CAmrPayloadHeader::Decode

// Decode the payload header from a given buffer at the given position.

// ---------------------------------------------------------------------------

//

void CAmrPayloadHeader::Decode( const TUint8* aBuffer,

        TInt& aByteIndex, TInt& aBitIndex )

    {

    DP_AMR_ENCODE( "CAmrPayloadHeader::Decode" );

    TStreamDecoder decoder;

    decoder.Initialize( aBuffer, aByteIndex, aBitIndex );

    iCmr = TAmrModeRequest( decoder.Decode( KCMRFieldBits ) );

    // Update Byte and Bit positions

    aByteIndex = decoder.ByteIndex( );

    aBitIndex = decoder.BitIndex( );

    }