engine.h Example File

multimedia/spectrum/app/engine.h
/**************************************************************************** ** ** Copyright (C) 2017 The Qt Company Ltd. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the examples of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:BSD$ ** Commercial License Usage ** Licensees holding valid commercial Qt licenses may use this file in ** accordance with the commercial license agreement provided with the ** Software or, alternatively, in accordance with the terms contained in ** a written agreement between you and The Qt Company. For licensing terms ** and conditions see https://www.qt.io/terms-conditions. For further ** information use the contact form at https://www.qt.io/contact-us. ** ** BSD License Usage ** Alternatively, 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 The Qt Company Ltd 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 <QAudioDeviceInfo> #include <QAudioFormat> #include <QBuffer> #include <QByteArray> #include <QDir> #include <QObject> #include <QVector> #ifdef DUMP_CAPTURED_AUDIO #define DUMP_DATA #endif #ifdef DUMP_SPECTRUM #define DUMP_DATA #endif class FrequencySpectrum; class QAudioInput; class QAudioOutput; /** * This class interfaces with the Qt Multimedia 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: explicit 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 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 bytes. */ 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 bytes. */ qint64 playPosition() const { return m_playPosition; } /** * Length of the internal engine buffer. * \return Buffer length in bytes. */ qint64 bufferLength() const; /** * Amount of data held in the buffer. * \return Data length in bytes. */ qint64 dataLength() const { return m_dataLength; } /** * 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 bufferLengthChanged(qint64 duration); /** * Amount of data in buffer has changed. * \param Length of data in bytes */ void dataLengthChanged(qint64 duration); /** * Position of the audio input device has changed. * \param position Position in bytes */ void recordPositionChanged(qint64 position); /** * Position of the audio output device has changed. * \param position Position in bytes */ 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 analyzed */ void levelChanged(qreal rmsLevel, qreal peakLevel, int numSamples); /** * Spectrum has changed. * \param position Position of start of window in bytes * \param length Length of window in bytes * \param spectrum Resulting frequency spectrum */ void spectrumChanged(qint64 position, qint64 length, const FrequencySpectrum &spectrum); /** * Buffer containing audio data has changed. * \param position Position of start of buffer in bytes * \param buffer Buffer */ void bufferChanged(qint64 position, qint64 length, const QByteArray &buffer); private slots: void audioNotify(); void audioStateChanged(QAudio::State state); void audioDataReady(); void spectrumChanged(const FrequencySpectrum &spectrum); private: void resetAudioDevices(); 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; WavFile* m_file; // We need a second file handle via which to read data into m_buffer // for analysis WavFile* m_analysisFile; 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; QString m_audioOutputCategory; qint64 m_playPosition; QBuffer m_audioOutputIODevice; QByteArray m_buffer; qint64 m_bufferPosition; qint64 m_bufferLength; qint64 m_dataLength; int m_levelBufferLength; qreal m_rmsLevel; qreal m_peakLevel; int m_spectrumBufferLength; QByteArray m_spectrumBuffer; SpectrumAnalyser m_spectrumAnalyser; qint64 m_spectrumPosition; int m_count; #ifdef DUMP_DATA QDir m_outputDir; #endif }; #endif // ENGINE_H

© 2021 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners. The documentation provided herein is licensed under the terms of the GNU Free Documentation License version 1.3 as published by the Free Software Foundation. Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners.