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📄 AudioAnalyser.js

📊 Analysis Summary

Metric	Count
🔧 Functions	2
🧱 Classes	1
📊 Variables & Constants	1

📚 Table of Contents

• Variables & Constants
• Functions
• Classes

🛠️ File Location:

📂 src/audio/AudioAnalyser.js

Variables & Constants

Name	Type	Kind	Value	Exported
value	number	let/var	0	✗

---

Functions

AudioAnalyser.getFrequencyData(): Uint8Array<ArrayBufferLike>

JSDoc:

/**
     * Returns an array with frequency data of the audio.
     *
     * Each item in the array represents the decibel value for a specific frequency.
     * The frequencies are spread linearly from 0 to 1/2 of the sample rate.
     * For example, for 48000 sample rate, the last item of the array will represent
     * the decibel value for 24000 Hz.
     *
     * @return {Uint8Array} The frequency data.
     */

Returns: Uint8Array<ArrayBufferLike>

Calls:

• this.analyser.getByteFrequencyData

Code

getFrequencyData() {

        this.analyser.getByteFrequencyData( this.data );

        return this.data;

    }

AudioAnalyser.getAverageFrequency(): number

JSDoc:

/**
     * Returns the average of the frequencies returned by {@link AudioAnalyser#getFrequencyData}.
     *
     * @return {number} The average frequency.
     */

Returns: number

Calls:

• this.getFrequencyData

Code

getAverageFrequency() {

        let value = 0;
        const data = this.getFrequencyData();

        for ( let i = 0; i < data.length; i ++ ) {

            value += data[ i ];

        }

        return value / data.length;

    }

---

Classes

AudioAnalyser

Class Code

class AudioAnalyser {

    /**
     * Constructs a new audio analyzer.
     *
     * @param {Audio} audio - The audio to analyze.
     * @param {number} [fftSize=2048] - The window size in samples that is used when performing a Fast Fourier Transform (FFT) to get frequency domain data.
     */
    constructor( audio, fftSize = 2048 ) {

        /**
         * The global audio listener.
         *
         * @type {AnalyserNode}
         */
        this.analyser = audio.context.createAnalyser();
        this.analyser.fftSize = fftSize;

        /**
         * Holds the analyzed data.
         *
         * @type {Uint8Array}
         */
        this.data = new Uint8Array( this.analyser.frequencyBinCount );

        audio.getOutput().connect( this.analyser );

    }

    /**
     * Returns an array with frequency data of the audio.
     *
     * Each item in the array represents the decibel value for a specific frequency.
     * The frequencies are spread linearly from 0 to 1/2 of the sample rate.
     * For example, for 48000 sample rate, the last item of the array will represent
     * the decibel value for 24000 Hz.
     *
     * @return {Uint8Array} The frequency data.
     */
    getFrequencyData() {

        this.analyser.getByteFrequencyData( this.data );

        return this.data;

    }

    /**
     * Returns the average of the frequencies returned by {@link AudioAnalyser#getFrequencyData}.
     *
     * @return {number} The average frequency.
     */
    getAverageFrequency() {

        let value = 0;
        const data = this.getFrequencyData();

        for ( let i = 0; i < data.length; i ++ ) {

            value += data[ i ];

        }

        return value / data.length;

    }

}

Methods

getFrequencyData(): Uint8Array<ArrayBufferLike>

Code

getFrequencyData() {

        this.analyser.getByteFrequencyData( this.data );

        return this.data;

    }

getAverageFrequency(): number

Code

getAverageFrequency() {

        let value = 0;
        const data = this.getFrequencyData();

        for ( let i = 0; i < data.length; i ++ ) {

            value += data[ i ];

        }

        return value / data.length;

    }

---