Qt Reference Documentation

# audioinput.h Example File

multimedia/audioinput/audioinput.h

     /****************************************************************************
     **
     ** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
     ** All rights reserved.
     ** Contact: Nokia Corporation (qt-info@nokia.com)
     **
     ** 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:
     **
     ** "Redistribution and use in source and binary forms, with or without
     ** modification, are permitted provided that the following conditions are
     ** met:
     **   * Redistributions of source code must retain the above copyright
     **     notice, this list of conditions and the following disclaimer.
     **   * Redistributions in binary form must reproduce the above copyright
     **     notice, this list of conditions and the following disclaimer in
     **     the documentation and/or other materials provided with the
     **     distribution.
     **   * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
     **     the names of its contributors may be used to endorse or promote
     **     products derived from this software without specific prior written
     **     permission.
     **
     ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
     ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
     ** $QT_END_LICENSE$
     **
     ****************************************************************************/

     #ifndef AUDIOINPUT_H
     #define AUDIOINPUT_H

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

     #include <qaudioinput.h>

     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;
         quint16 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 notified();
         void readMore();
         void toggleMode();
         void toggleSuspend();
         void stateChanged(QAudio::State state);
         void deviceChanged(int index);

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

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

         static const QString PushModeLabel;
         static const QString PullModeLabel;
         static const QString SuspendLabel;
         static const QString ResumeLabel;
     };

     #endif