Qt Reference Documentation

spectrograph.h Example File

demos/spectrum/app/spectrograph.h
 /****************************************************************************
 **
 ** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
 ** All rights reserved.
 ** Contact: Nokia Corporation ([email protected])
 **
 ** 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 SPECTROGRAPH_H
 #define SPECTROGRAPH_H

 #include <QWidget>
 #include "frequencyspectrum.h"

 QT_FORWARD_DECLARE_CLASS(QMouseEvent)

 /**
  * Widget which displays a spectrograph showing the frequency spectrum
  * of the window of audio samples most recently analysed by the Engine.
  */
 class Spectrograph : public QWidget {
     Q_OBJECT
 public:
     Spectrograph(QWidget *parent = 0);
     ~Spectrograph();

     void setParams(int numBars, qreal lowFreq, qreal highFreq);

     // QObject
     void timerEvent(QTimerEvent *event);

     // QWidget
     void paintEvent(QPaintEvent *event);
     void mousePressEvent(QMouseEvent *event);

 signals:
     void infoMessage(const QString &message, int intervalMs);

 public slots:
     void reset();
     void spectrumChanged(const FrequencySpectrum &spectrum);

 private:
     int barIndex(qreal frequency) const;
     QPair<qreal, qreal> barRange(int barIndex) const;
     void updateBars();

     void selectBar(int index);

 private:
     struct Bar {
         Bar() : value(0.0), clipped(false) { }
         qreal   value;
         bool    clipped;
     };

     QVector<Bar>        m_bars;
     int                 m_barSelected;
     int                 m_timerId;
     qreal               m_lowFreq;
     qreal               m_highFreq;
     FrequencySpectrum   m_spectrum;

 };

 #endif // SPECTROGRAPH_H
X

Thank you for giving your feedback.

Make sure it is related to this specific page. For more general bugs and requests, please use the Qt Bug Tracker.