audiooutput.h Example File

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  #ifndef AUDIOOUTPUT_H
  #define AUDIOOUTPUT_H

  #include <math.h>

  #include <QAudioOutput>
  #include <QByteArray>
  #include <QComboBox>
  #include <QIODevice>
  #include <QLabel>
  #include <QMainWindow>
  #include <QObject>
  #include <QPushButton>
  #include <QSlider>
  #include <QTimer>

  class Generator : public QIODevice
  {
      Q_OBJECT

  public:
      Generator(const QAudioFormat &format, qint64 durationUs, int sampleRate, QObject *parent);
      ~Generator();

      void start();
      void stop();

      qint64 readData(char *data, qint64 maxlen);
      qint64 writeData(const char *data, qint64 len);
      qint64 bytesAvailable() const;

  private:
      void generateData(const QAudioFormat &format, qint64 durationUs, int sampleRate);

  private:
      qint64 m_pos;
      QByteArray m_buffer;
  };

  class AudioTest : public QMainWindow
  {
      Q_OBJECT

  public:
      AudioTest();
      ~AudioTest();

  private:
      void initializeWindow();
      void initializeAudio();
      void createAudioOutput();

  private:
      QTimer *m_pushTimer;

      // Owned by layout
      QPushButton *m_modeButton;
      QPushButton *m_suspendResumeButton;
      QComboBox *m_deviceBox;
      QLabel *m_volumeLabel;
      QSlider *m_volumeSlider;

      QAudioDeviceInfo m_device;
      Generator *m_generator;
      QAudioOutput *m_audioOutput;
      QIODevice *m_output; // not owned
      QAudioFormat m_format;

      bool m_pullMode;
      QByteArray m_buffer;

  private slots:
      void pushTimerExpired();
      void toggleMode();
      void toggleSuspendResume();
      void deviceChanged(int index);
      void volumeChanged(int);
  };

  #endif // AUDIOOUTPUT_H