/****************************************************************************+
−
**+
−
** 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 ENGINE_H+
−
#define ENGINE_H+
−
+
−
#include "spectrum.h"+
−
#include "spectrumanalyser.h"+
−
#include "wavfile.h"+
−
+
−
#include <QObject>+
−
#include <QByteArray>+
−
#include <QBuffer>+
−
#include <QVector>+
−
#include <QtMultimedia/QAudioDeviceInfo>+
−
#include <QtMultimedia/QAudioFormat>+
−
+
−
#ifdef DUMP_CAPTURED_AUDIO+
−
#define DUMP_DATA+
−
#endif+
−
+
−
#ifdef DUMP_SPECTRUM+
−
#define DUMP_DATA+
−
#endif+
−
+
−
#ifdef DUMP_DATA+
−
#include <QDir>+
−
#endif+
−
+
−
class FrequencySpectrum;+
−
QT_FORWARD_DECLARE_CLASS(QAudioInput)+
−
QT_FORWARD_DECLARE_CLASS(QAudioOutput)+
−
QT_FORWARD_DECLARE_CLASS(QFile)+
−
+
−
/**+
−
 * This class interfaces with the QtMultimedia audio classes, and also with+
−
 * the SpectrumAnalyser class.  Its role is to manage the capture and playback+
−
 * of audio data, meanwhile performing real-time analysis of the audio level+
−
 * and frequency spectrum.+
−
 */+
−
class Engine : public QObject {+
−
    Q_OBJECT+
−
public:+
−
    Engine(QObject *parent = 0);+
−
    ~Engine();+
−
+
−
    const QList<QAudioDeviceInfo>& availableAudioInputDevices() const+
−
                                    { return m_availableAudioInputDevices; }+
−
+
−
    const QList<QAudioDeviceInfo>& availableAudioOutputDevices() const+
−
                                    { return m_availableAudioOutputDevices; }+
−
+
−
    QAudio::Mode mode() const       { return m_mode; }+
−
    QAudio::State state() const     { return m_state; }+
−
+
−
    /**+
−
     * \return Reference to internal audio buffer+
−
     * \note This reference is valid for the lifetime of the Engine+
−
     */+
−
    const QByteArray& buffer() const    { return m_buffer; }+
−
+
−
    /**+
−
     * \return Current audio format+
−
     * \note May be QAudioFormat() if engine is not initialized+
−
     */+
−
    const QAudioFormat& format() const  { return m_format; }+
−
+
−
    /**+
−
     * Stop any ongoing recording or playback, and reset to ground state.+
−
     */+
−
    void reset();+
−
+
−
    /**+
−
     * Load data from WAV file+
−
     */+
−
    bool loadFile(const QString &fileName);+
−
+
−
    /**+
−
     * Generate tone+
−
     */+
−
    bool generateTone(const Tone &tone);+
−
+
−
    /**+
−
     * Generate tone+
−
     */+
−
    bool generateSweptTone(qreal amplitude);+
−
+
−
    /**+
−
     * Initialize for recording+
−
     */+
−
    bool initializeRecord();+
−
+
−
    /**+
−
     * Position of the audio input device.+
−
     * \return Position in microseconds.+
−
     */+
−
    qint64 recordPosition() const   { return m_recordPosition; }+
−
+
−
    /**+
−
     * RMS level of the most recently processed set of audio samples.+
−
     * \return Level in range (0.0, 1.0)+
−
     */+
−
    qreal rmsLevel() const          { return m_rmsLevel; }+
−
+
−
    /**+
−
     * Peak level of the most recently processed set of audio samples.+
−
     * \return Level in range (0.0, 1.0)+
−
     */+
−
    qreal peakLevel() const         { return m_peakLevel; }+
−
+
−
    /**+
−
     * Position of the audio output device.+
−
     * \return Position in microseconds.+
−
     */+
−
    qint64 playPosition() const     { return m_playPosition; }+
−
+
−
    /**+
−
     * Length of the internal engine buffer.+
−
     * \return Buffer length in microseconds.+
−
     */+
−
    qint64 bufferDuration() const;+
−
+
−
    /**+
−
     * Amount of data held in the buffer.+
−
     * \return Data duration in microseconds.+
−
     */+
−
    qint64 dataDuration() const;+
−
+
−
    /**+
−
     * Returns the size of the underlying audio buffer in bytes.+
−
     * This should be an approximation of the capture latency.+
−
     */+
−
    qint64 audioBufferLength() const;+
−
+
−
    /**+
−
     * Set window function applied to audio data before spectral analysis.+
−
     */+
−
    void setWindowFunction(WindowFunction type);+
−
+
−
public slots:+
−
    void startRecording();+
−
    void startPlayback();+
−
    void suspend();+
−
    void setAudioInputDevice(const QAudioDeviceInfo &device);+
−
    void setAudioOutputDevice(const QAudioDeviceInfo &device);+
−
+
−
signals:+
−
    void stateChanged(QAudio::Mode mode, QAudio::State state);+
−
+
−
    /**+
−
     * Informational message for non-modal display+
−
     */+
−
    void infoMessage(const QString &message, int durationMs);+
−
+
−
    /**+
−
     * Error message for modal display+
−
     */+
−
    void errorMessage(const QString &heading, const QString &detail);+
−
+
−
    /**+
−
     * Format of audio data has changed+
−
     */+
−
    void formatChanged(const QAudioFormat &format);+
−
+
−
    /**+
−
     * Length of buffer has changed.+
−
     * \param duration Duration in microseconds+
−
     */+
−
    void bufferDurationChanged(qint64 duration);+
−
+
−
    /**+
−
     * Amount of data in buffer has changed.+
−
     * \param duration Duration of data in microseconds+
−
     */+
−
    void dataDurationChanged(qint64 duration);+
−
+
−
    /**+
−
     * Position of the audio input device has changed.+
−
     * \param position Position in microseconds+
−
     */+
−
    void recordPositionChanged(qint64 position);+
−
+
−
    /**+
−
     * Position of the audio output device has changed.+
−
     * \param position Position in microseconds+
−
     */+
−
    void playPositionChanged(qint64 position);+
−
+
−
    /**+
−
     * Level changed+
−
     * \param rmsLevel RMS level in range 0.0 - 1.0+
−
     * \param peakLevel Peak level in range 0.0 - 1.0+
−
     * \param numSamples Number of audio samples analysed+
−
     */+
−
    void levelChanged(qreal rmsLevel, qreal peakLevel, int numSamples);+
−
+
−
    /**+
−
     * Spectrum has changed.+
−
     * \param position Position of start of window in microseconds+
−
     * \param length   Length of window in microseconds+
−
     * \param spectrum Resulting frequency spectrum+
−
     */+
−
    void spectrumChanged(qint64 position, qint64 length, const FrequencySpectrum &spectrum);+
−
+
−
private slots:+
−
    void audioNotify();+
−
    void audioStateChanged(QAudio::State state);+
−
    void audioDataReady();+
−
    void spectrumChanged(const FrequencySpectrum &spectrum);+
−
+
−
private:+
−
    bool initialize();+
−
    bool selectFormat();+
−
    void stopRecording();+
−
    void stopPlayback();+
−
    void setState(QAudio::State state);+
−
    void setState(QAudio::Mode mode, QAudio::State state);+
−
    void setFormat(const QAudioFormat &format);+
−
    void setRecordPosition(qint64 position, bool forceEmit = false);+
−
    void setPlayPosition(qint64 position, bool forceEmit = false);+
−
    void calculateLevel(qint64 position, qint64 length);+
−
    void calculateSpectrum(qint64 position);+
−
    void setLevel(qreal rmsLevel, qreal peakLevel, int numSamples);+
−
+
−
#ifdef DUMP_DATA+
−
    void createOutputDir();+
−
    QString outputPath() const { return m_outputDir.path(); }+
−
#endif+
−
+
−
#ifdef DUMP_CAPTURED_AUDIO+
−
    void dumpData();+
−
#endif+
−
+
−
private:+
−
    QAudio::Mode        m_mode;+
−
    QAudio::State       m_state;+
−
+
−
    bool                m_generateTone;+
−
    SweptTone           m_tone;+
−
+
−
    QFile*              m_file;+
−
    WavFile             m_wavFile;+
−
+
−
    QAudioFormat        m_format;+
−
+
−
    const QList<QAudioDeviceInfo> m_availableAudioInputDevices;+
−
    QAudioDeviceInfo    m_audioInputDevice;+
−
    QAudioInput*        m_audioInput;+
−
    QIODevice*          m_audioInputIODevice;+
−
    qint64              m_recordPosition;+
−
+
−
    const QList<QAudioDeviceInfo> m_availableAudioOutputDevices;+
−
    QAudioDeviceInfo    m_audioOutputDevice;+
−
    QAudioOutput*       m_audioOutput;+
−
    qint64              m_playPosition;+
−
    QBuffer             m_audioOutputIODevice;+
−
+
−
    QByteArray          m_buffer;+
−
    qint64              m_dataLength;+
−
+
−
    qreal               m_rmsLevel;+
−
    qreal               m_peakLevel;+
−
+
−
    int                 m_spectrumLengthBytes;+
−
    QByteArray          m_spectrumBuffer;+
−
    SpectrumAnalyser    m_spectrumAnalyser;+
−
    qint64              m_spectrumPosition;+
−
+
−
    int                 m_count;+
−
+
−
#ifdef DUMP_DATA+
−
    QDir                m_outputDir;+
−
#endif+
−
+
−
};+
−
+
−
#endif // ENGINE_H+
−