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Diffstat (limited to 'examples/multimedia/spectrum/engine.h')
| -rw-r--r-- | examples/multimedia/spectrum/engine.h | 289 |
1 files changed, 289 insertions, 0 deletions
diff --git a/examples/multimedia/spectrum/engine.h b/examples/multimedia/spectrum/engine.h new file mode 100644 index 000000000..9e8ba51d0 --- /dev/null +++ b/examples/multimedia/spectrum/engine.h @@ -0,0 +1,289 @@ +// Copyright (C) 2017 The Qt Company Ltd. +// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause + +#ifndef ENGINE_H +#define ENGINE_H + +#include "spectrum.h" +#include "spectrumanalyser.h" + +#include <QAudioDevice> +#include <QAudioFormat> +#include <QBuffer> +#include <QByteArray> +#include <QDir> +#include <QList> +#include <QMediaDevices> +#include <QObject> +#include <QTimer> +#include <QWaveDecoder> + +#ifdef DUMP_CAPTURED_AUDIO +# define DUMP_DATA +#endif + +#ifdef DUMP_SPECTRUM +# define DUMP_DATA +#endif + +class FrequencySpectrum; +QT_BEGIN_NAMESPACE +class QAudioSource; +class QAudioSink; +QT_END_NAMESPACE + +/** + * 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 = nullptr); + ~Engine(); + + const QList<QAudioDevice> &availableAudioInputDevices() const + { + return m_availableAudioInputDevices; + } + + const QList<QAudioDevice> &availableAudioOutputDevices() const + { + return m_availableAudioOutputDevices; + } + + QAudioDevice::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 QAudioDevice &device); + void setAudioOutputDevice(const QAudioDevice &device); + +signals: + void stateChanged(QAudioDevice::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 initAudioDevices(); + 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(QAudioDevice::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); + void emitError(QAudio::Error error); + +#ifdef DUMP_DATA + void createOutputDir(); + QString outputPath() const + { + return m_outputDir.path(); + } +#endif + +#ifdef DUMP_CAPTURED_AUDIO + void dumpData(); +#endif + +private: + QAudioDevice::Mode m_mode; + QAudio::State m_state; + QMediaDevices *m_devices; + + bool m_generateTone; + SweptTone m_tone; + + QWaveDecoder *m_file; + // We need a second file handle via which to read data into m_buffer + // for analysis + QWaveDecoder *m_analysisFile; + + QAudioFormat m_format; + + QList<QAudioDevice> m_availableAudioInputDevices; + QAudioDevice m_audioInputDevice; + QAudioSource *m_audioInput; + QIODevice *m_audioInputIODevice; + qint64 m_recordPosition; + + QList<QAudioDevice> m_availableAudioOutputDevices; + QAudioDevice m_audioOutputDevice; + QAudioSink *m_audioOutput; + 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; + QTimer *m_notifyTimer = nullptr; + +#ifdef DUMP_DATA + QDir m_outputDir; +#endif +}; + +#endif // ENGINE_H |