source: trunk/demos/spectrum/app/engine.h@ 858

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#ifndef ENGINE_H
#define ENGINE_H

#include "spectrum.h"
#include "spectrumanalyser.h"
#include "wavfile.h"

#include <QObject>
#include <QByteArray>
#include <QBuffer>
#include <QVector>
#include <QtMultimedia/QAudioDeviceInfo>
#include <QtMultimedia/QAudioFormat>

#ifdef DUMP_CAPTURED_AUDIO
#define DUMP_DATA
#endif

#ifdef DUMP_SPECTRUM
#define DUMP_DATA
#endif

#ifdef DUMP_DATA
#include <QDir>
#endif

class FrequencySpectrum;
QT_FORWARD_DECLARE_CLASS(QAudioInput)
QT_FORWARD_DECLARE_CLASS(QAudioOutput)
QT_FORWARD_DECLARE_CLASS(QFile)

/**
 * This class interfaces with the QtMultimedia audio classes, and also with
 * the SpectrumAnalyser class.  Its role is to manage the capture and playback
 * of audio data, meanwhile performing real-time analysis of the audio level
 * and frequency spectrum.
 */
class Engine : public QObject {
    Q_OBJECT
public:
    Engine(QObject *parent = 0);
    ~Engine();

    const QList<QAudioDeviceInfo>& availableAudioInputDevices() const
                                    { return m_availableAudioInputDevices; }

    const QList<QAudioDeviceInfo>& availableAudioOutputDevices() const
                                    { return m_availableAudioOutputDevices; }

    QAudio::Mode mode() const       { return m_mode; }
    QAudio::State state() const     { return m_state; }

    /**
     * \return Current audio format
     * \note May be QAudioFormat() if engine is not initialized
     */
    const QAudioFormat& format() const  { return m_format; }

    /**
     * Stop any ongoing recording or playback, and reset to ground state.
     */
    void reset();

    /**
     * Load data from WAV file
     */
    bool loadFile(const QString &fileName);

    /**
     * Generate tone
     */
    bool generateTone(const Tone &tone);

    /**