- Qt 5.5
- Qt Multimedia
- Spectrum Example
- frequencyspectrum.h Example File
- Qt 5.5.1 Reference Documentation

# frequencyspectrum.h Example File

spectrum/app/frequencyspectrum.h

    /****************************************************************************
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    ** This file is part of the examples of the Qt Toolkit.
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    #ifndef FREQUENCYSPECTRUM_H
    #define FREQUENCYSPECTRUM_H

    #include <QtCore/QVector>

    /**
     * Represents a frequency spectrum as a series of elements, each of which
     * consists of a frequency, an amplitude and a phase.
     */
    class FrequencySpectrum {
    public:
        FrequencySpectrum(int numPoints = 0);

        struct Element {
            Element()
            :   frequency(0.0), amplitude(0.0), phase(0.0), clipped(false)
            { }

            /**
             * Frequency in Hertz
             */
            qreal frequency;

            /**
             * Amplitude in range [0.0, 1.0]
             */
            qreal amplitude;

            /**
             * Phase in range [0.0, 2*PI]
             */
            qreal phase;

            /**
             * Indicates whether value has been clipped during spectrum analysis
             */
            bool clipped;
        };

        typedef QVector<Element>::iterator iterator;
        typedef QVector<Element>::const_iterator const_iterator;

        void reset();

        int count() const;
        Element& operator[](int index);
        const Element& operator[](int index) const;
        iterator begin();
        iterator end();
        const_iterator begin() const;
        const_iterator end() const;

    private:
        QVector<Element> m_elements;

    };

    #endif // FREQUENCYSPECTRUM_H