multimediacommscontroller/mmccjitterbuffer/inc/mcccngenerator.h
changeset 0 1bce908db942
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/multimediacommscontroller/mmccjitterbuffer/inc/mcccngenerator.h	Tue Feb 02 01:04:58 2010 +0200
@@ -0,0 +1,156 @@
+/*
+* Copyright (c) 2004-2006 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:    Provides a comfort noise generator class
+*
+*/
+
+
+
+
+#ifndef MCCCNGENERATOR_H
+#define MCCCNGENERATOR_H
+
+#include <e32base.h>
+#include <mmf/common/mmfutilities.h>
+
+// FORWARD DECLARATIONS
+class CMMFDevSound;
+class CErrorConcealmentIntfc;
+
+/**
+* MCC Comfort noise generator
+*
+* @lib MMccJitterBuffer.lib
+* @since Series 60 3.0
+*/
+NONSHARABLE_CLASS( CMccCnGenerator ) : public CBase
+    {
+    public:  // Constructors and destructor 
+        
+        /**
+        * Two phased constructor
+        */
+        static CMccCnGenerator* NewL( const TFourCC& aAudioType, 
+                CMMFDevSound& aDevSound );
+
+        /**
+        * Destructor
+        */
+        virtual ~CMccCnGenerator();
+
+    public: // New functions
+
+        /**
+        * Generates an SID packet to given buffer
+        * @since Series 60 3.0
+        * @param aPayload Buffer to be filled with SID data
+        * @param aRequestSize Amount of data to be generated to buffer.
+        * @return void
+        */
+        void GenerateSidPacket( TDes8& aPayload, TInt aRequestSize );
+        
+        /**
+        * Jitterbuffer has noted that frames were missing, so error concealment
+        * needs to be done to some frames. This function calls the error 
+        * concealment interface's error concealment function.
+        * @since Series 60 3.0
+        * @param None
+        * @return void
+        */
+        void ConcealErrorForNextFrame() const;
+        
+        /**
+        * Returns the current DTX status
+        * @since Series 60 3.0
+        * @param None
+        * @return TBool ETrue if DTX period ongoing
+        */
+        inline TBool DtxPeriodStatus() const
+            {
+            return ( iDtxPeriodStarted );
+            }
+        
+        /**
+        * Decide whether we are in DTX period or in normal speech period
+        * @since Series 60 3.0
+        * @param aData Buffer containing the data
+        * @return void
+        */
+        void DoDtxDecision( const TDesC8& aData );
+        
+        /**
+        * Check if the given databuffer is a SID frame for current codec
+        * @since Series 60 3.0
+        * @param aData Buffer containing the data
+        * @return TBool ETrue if the aBuffer is a SID for current codec
+        */
+        TBool IsSidBuffer( const TDesC8& aData ) const;
+
+    private: // New functions
+
+        /**
+        * Generates an AMR CN packet into aPayload
+        * @since Series 60 3.0
+        * @param aPayload
+        * @return void
+        */
+        void GenerateAmrNoDataPacket( TDes8& aPayload ) const;
+        
+        /**
+        * Generates an VoIP NO_DATA frame into aPayload
+        * @since Series 60 3.0
+        * @param aPayload Buffer to be filled with VoIP NO_DATA information
+        * @param aRequestSize Amount of data to be generated to buffer.
+        * @return void
+        */
+        void GenerateVoIPNoDataPacket( TDes8& aPayload, TInt aRequestSize ) const;
+
+    private: //Constructors
+
+        /**
+        * C++ default constructor.
+        */
+        CMccCnGenerator( const TFourCC& aAudioType, CMMFDevSound& aDevSound );
+
+        /**
+        * By default Symbian 2nd phase constructor is private.
+        */
+        void ConstructL();
+           
+    private:    // Data
+                
+        // Audio type
+        TFourCC iAudioType;
+        
+        // Sound device for Error Concealment IF creation
+        CMMFDevSound& iDevSound;
+        
+        // Error concealment interface
+        CErrorConcealmentIntfc* iErrorConcealer;
+        
+        // Generated CN frames
+        TInt iGeneratedCnFrames;
+        
+        // DTX period started
+        TBool iDtxPeriodStarted;
+      
+    private:    // Friend classes
+    
+    // Friend class for EUNIT tests
+    #ifdef TEST_EUNIT
+        friend class UT_CMccCnGenerator;
+    #endif
+    };
+
+#endif  // MCCCNGENERATOR_H