examples/ForumNokia/AudioStreamExample/inc/AudioStreamEngine.h

/*
 * Copyright © 2008 Nokia Corporation.
 */

#ifndef AUDIOSTREAMENGINE_H
#define AUDIOSTREAMENGINE_H

// INCLUDES
#include <e32base.h>
#include <aknviewappui.h> 

#include <mda\common\audio.h>
#include <MdaAudioInputStream.h>    // audio input stream
#include <MdaAudioOutputStream.h>   // audio output stream

#include "AudioStream.hrh"
#include "AudioStreamView.h"    
#include "AudioStreamAppUi.h"   

// FORWARD DECLARATIONS
class CAudioStreamView;

// CLASS DECLARATION

class CAudioStreamEngine : public CBase, MMdaAudioInputStreamCallback, 
    MMdaAudioOutputStreamCallback
{
public:
    static CAudioStreamEngine* NewL(CAudioStreamAppUi* /* aAppUi */);

    static CAudioStreamEngine* NewLC(CAudioStreamAppUi* /* aAppUi */);


    ~CAudioStreamEngine();
        

public: // New functions
    
    void Play();
    void Record();
    void Stop();
    
    void LoadAudioFileL();
    void SaveAudioFileL();

    void SetEncodingL(TBool aAmr);
    
private: // in-class methods

    TPtr8& CAudioStreamEngine::GetFrame(TUint aFrameIdx);
    TPtr8& CAudioStreamEngine::GetPlaybackFrames(TUint aLastFrame);

    void ShowMessage(const TDesC& /* aMsg */, TBool /* aReset=false */);
    
    virtual void MaiscOpenComplete(TInt aError);
    virtual void MaiscBufferCopied(TInt aError, const TDesC8& aBuffer);
    virtual void MaiscRecordComplete(TInt aError);

    virtual void MaoscOpenComplete(TInt aError);
    virtual void MaoscBufferCopied(TInt aError, const TDesC8& aBuffer);
    
    virtual void MaoscPlayComplete(TInt aError);

    static TInt BackgroundStop( TAny *aStream );
    
public: // Functions from base classes

private: // Basic two-phase EPOC constructors

    void ConstructL();
 
    CAudioStreamEngine(CAudioStreamAppUi* /* aAppUi */);

private:    

    // enumeration of input/output stream status
    enum TStatus
        {
        ENotReady,
        EOpen
        };

        
private:    // data members

    // application UI object reference
    CAudioStreamAppUi* iAppUi;
    // audio input stream object reference
    CMdaAudioInputStream* iInputStream;
    // audio output stream object reference
    CMdaAudioOutputStream* iOutputStream;

    // Handle to CCoeEnv's file server
    RFs iFs;

    // Do we use AMR-NB encoding?
    TBool iUseAMR;
    // The path to the sample audio file (sample.aud or sample.amr)
    TFileName iAudioFilePath;
    // The audio file to be used (sample.aud or sample.amr)
    TFileName iAudioFile;   
    // The frame size for the current encoding
    TUint iFrameSize;
    // The number of frames to be buffered
    TUint iFrameCount;

    // A buffer containing the audio frames
    HBufC8* iStreamBuffer;  
    // Modifiable pointer used to reference a single frame in iStreamBuffer 
    // while recording, and all the valid frames in iStreamBuffer while playback (the
    // iStreamBuffer might not always be fully recorded in this example).
    TPtr8 iFramePtr;
    // Buffer status (does it contain valid audio data)
    TBool iBufferOK;
    // The default encoding used by the platform
    TFourCC iDefaultEncoding;
    // The encoding we are currently using
    TFourCC iCurrentEncoding;

    // Audio data stream settings for input and output streams
    TMdaAudioDataSettings iStreamSettings;
    // Status enumeration of input stream
    TStatus iInputStatus;
    // Status enumeration of output stream  
    TStatus iOutputStatus;
    // Index of audio data block currently being played/recorded on the buffer
    TUint iStreamIdx;
    // Application status message displayed to user
    TBuf<255> iMsg;
    // Stream start (first audio block in buffer) and end index
    TUint iStreamStart;
    TUint iStreamEnd;
    
    CIdle* iStop;
    
};

#endif // AUDIOSTREAMENGINE_H

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