Qt 5.9 | Qt Multimedia | Audio Input Example | audioinput.h Example File

Qt 5.9.4 Reference Documentation

# audioinput.h Example File

multimedia/audioinput/audioinput.h

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      #ifndef AUDIOINPUT_H
      #define AUDIOINPUT_H

      #include <QAudioInput>
      #include <QByteArray>
      #include <QComboBox>
      #include <QMainWindow>
      #include <QObject>
      #include <QPixmap>
      #include <QPushButton>
      #include <QSlider>
      #include <QWidget>

      class AudioInfo : public QIODevice
      {
          Q_OBJECT

      public:
          AudioInfo(const QAudioFormat &format, QObject *parent);
          ~AudioInfo();

          void start();
          void stop();

          qreal level() const { return m_level; }

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

      private:
          const QAudioFormat m_format;
          quint32 m_maxAmplitude;
          qreal m_level; // 0.0 <= m_level <= 1.0

      signals:
          void update();
      };

      class RenderArea : public QWidget
      {
          Q_OBJECT

      public:
          RenderArea(QWidget *parent = 0);

          void setLevel(qreal value);

      protected:
          void paintEvent(QPaintEvent *event) override;

      private:
          qreal m_level;
          QPixmap m_pixmap;
      };

      class InputTest : public QMainWindow
      {
          Q_OBJECT

      public:
          InputTest();
          ~InputTest();

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

      private slots:
          void refreshDisplay();
          void readMore();
          void toggleMode();
          void toggleSuspend();
          void deviceChanged(int index);
          void sliderChanged(int value);

      private:
          // Owned by layout
          RenderArea *m_canvas;
          QPushButton *m_modeButton;
          QPushButton *m_suspendResumeButton;
          QComboBox *m_deviceBox;
          QSlider *m_volumeSlider;

          QAudioDeviceInfo m_device;
          AudioInfo *m_audioInfo;
          QAudioFormat m_format;
          QAudioInput *m_audioInput;
          QIODevice *m_input;
          bool m_pullMode;
          QByteArray m_buffer;
      };

      #endif // AUDIOINPUT_H