audiovisualize
v1.1.1
Published
AudioVisualize is a JavaScript module that leverages the power of the Web Audio API to visualize and analyze audio in your web applications. It provides an easy-to-use interface for loading audio, extracting audio data, and creating visualizations.
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AudioVisualize
AudioVisualize is a 3 kB JavaScript module that leverages the power of the Web Audio API to visualize and analyze audio in your web applications. It provides an easy-to-use interface for loading audio, extracting audio data, and creating visualizations. Check out these examples to learn how to bring your audio data to life with some simple visuals.
Possibilities
- Real-time Visualization: Create real-time visualizations of audio, including frequency spectrum analysis.
- Customizable: Adjust the audio analysis parameters to focus on the aspects that matter most to your application.
Installation
Easily install AudioVisualize via npm…
npm i audiovisualize
…or import the script from a CDN.
<script type="module">
import { AudioVisualize } from "https://unpkg.com/audiovisualize";
</script>
<script type="module">
import { AudioVisualize } from "https://cdn.jsdelivr.net/npm/[email protected]/audiovisualize.min.js"
</script>
Usage
You can create an instance of the AudioVisualize object and use its methods to load, analyze, and visualize audio. Use the loading method to load an audio file and set up event listeners for loading progress and playback events. Call the initialize method to set up the audio nodes for analysis.
// Create an instance of the AudioVisualize object.
const av = AudioVisualize;
av.loading(
// Path to your audio file
'path-to-your-audio-file.mp3',
() => {
// Audio loaded callback
console.log('Audio loaded');
},
(event) => {
// Progress update callback
console.log('Update event:', event);
},
() => {
// Audio ended callback
console.log('Audio ended');
}
);
// Create your custom audio visualizations here
When the AudioVisualize object is initialized, av.element
is created as an instance of an HTML <audio>
element that serves as the core component for loading, playing, and controlling audio files within a web page.
You can use the getFrequencies method to get the frequency data of the audio at any given moment. It returns an array of frequency values within a specified range.
const lowFrequency = 20; // Minimum frequency in Hz
const highFrequency = 20000; // Maximum frequency in Hz
const frequencies = av.getFrequencies(lowFrequency, highFrequency); // `frequencies` is an array of frequency data.
If you want to get the average frequency range over the entire audio track, you can use the getAverageRange method. This method will analyze the audio frame by frame and calculate the average over the specified frequency range.
const averageLowFrequency = 100; // Minimum frequency in Hz
const averageHighFrequency = 2000; // Maximum frequency in Hz
av.getAverageRange(averageLowFrequency, averageHighFrequency).then((average) => {
console.log('Average range over time:', average);
});
Adjust the frequency resolution, the FFT size, used for audio analysis. Default value is 2048
av.fftSize = 512;
Retrieve the sample rate of the audio context used, providing essential information about the rate at which audio data is processed. This value can be used to ensure accurate audio analysis and visualizations in your web applications.
console.log(av.audioContext.sampleRate);
Examples
Example 1
<canvas id="canvasElement"></canvas>
<script type="module">
import { AudioVisualize } from 'https://unpkg.com/audiovisualize';
const av = AudioVisualize;
av.loading(
'path-to-your-audio-file.mp3',
() => {
console.log('Audio duration', av.element.duration);
// Add the audio element to the body
document.body.appendChild(av.element);
av.element.setAttribute('controls', 'controls');
},
() => {
console.log('Buffered', av.element.buffered);
console.log('Current time', av.element.currentTime);
},
() => {
console.log('Audio ended', av.element.currentTime, av.element.duration);
}
);
const canvas = document.getElementById('canvasElement');
const ctx = canvas.getContext("2d");
function draw() {
if(!av.element.paused){
av.getFrequencies();
// Clear the canvas
ctx.clearRect(0, 0, canvas.width, canvas.height);
// Draw the waveform
ctx.strokeStyle = "black";
ctx.lineWidth = 1;
ctx.beginPath();
for (let i = 0; i < av.spectrum.length; i++) {
const x = (canvas.width / av.spectrum.length) * i;
const y = canvas.height - (canvas.height * av.spectrum[i]) / 255;
if (i === 0) {
ctx.moveTo(x, y);
} else {
ctx.lineTo(x, y);
}
}
ctx.stroke();
}
// Request the next animation frame
requestAnimationFrame(draw);
}
// Start the animation loop
draw();
</script>
Example 2
<canvas id="canvasElement"></canvas>
<script type="module">
import { AudioVisualize } from 'https://unpkg.com/audiovisualize';
const av = AudioVisualize;
av.loading(
'path-to-your-audio-file.mp3',
() => {
console.log('Audio duration', av.element.duration);
// Add the audio element to the body
document.body.appendChild(av.element);
av.element.setAttribute('controls', 'controls');
},
() => {
console.log('Buffered', av.element.buffered);
console.log('Current time', av.element.currentTime);
},
() => {
console.log('Audio ended', av.element.currentTime, av.element.duration);
}
);
const canvas = document.getElementById('canvasElement');
const ctx = canvas.getContext("2d");
function draw() {
if (!av.element.paused) {
// Calculate the average frequencies for bass, mids, and treble
const bassFrequency = av.getAverageBetweenFrequencies(20, 250); // Adjust the range for bass
const midFrequency = av.getAverageBetweenFrequencies(250, 1500); // Adjust the range for mids
const trebleFrequency = av.getAverageBetweenFrequencies(1500, 20000); // Adjust the range for treble
// Clear the canvas
ctx.clearRect(0, 0, canvas.width, canvas.height);
// Draw the bass line
ctx.strokeStyle = "blue";
ctx.lineWidth = 1;
ctx.beginPath();
const x1 = canvas.width / 4; // Position for bass
const y1 = canvas.height - (canvas.height * (bassFrequency / 255));
ctx.moveTo(x1, canvas.height);
ctx.lineTo(x1, y1);
ctx.stroke();
// Draw the mid line
ctx.strokeStyle = "green";
ctx.lineWidth = 1;
ctx.beginPath();
const x2 = canvas.width / 2; // Position for mids
const y2 = canvas.height - (canvas.height * (midFrequency / 255));
ctx.moveTo(x2, canvas.height);
ctx.lineTo(x2, y2);
ctx.stroke();
// Draw the treble line
ctx.strokeStyle = "red";
ctx.lineWidth = 1;
ctx.beginPath();
const x3 = (canvas.width * 3) / 4; // Position for treble
const y3 = canvas.height - (canvas.height * (trebleFrequency / 255));
ctx.moveTo(x3, canvas.height);
ctx.lineTo(x3, y3);
ctx.stroke();
}
// Request the next animation frame
requestAnimationFrame(draw);
}
// Start the animation loop
draw();
</script>