- Qt 5.5
- Qt Multimedia
- Audio Input Example
- audioinput.h Example File
- Qt 5.5.1 Reference Documentation

# audioinput.h Example File

audioinput/audioinput.h

    /****************************************************************************
    **
    ** Copyright (C) 2015 The Qt Company Ltd.
    ** Contact: http://www.qt.io/licensing/
    **
    ** This file is part of the examples of the Qt Toolkit.
    **
    ** $QT_BEGIN_LICENSE:BSD$
    ** You may use this file under the terms of the BSD license as follows:
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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);
        qint64 writeData(const char *data, qint64 len);

    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);

    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