--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/demos/spectrum/app/spectrograph.h	Fri Jun 11 14:24:45 2010 +0300
@@ -0,0 +1,96 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 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 SPECTROGRAPH_H
+#define SPECTROGRAPH_H
+
+#include <QWidget>
+#include "frequencyspectrum.h"
+
+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