audioEncoder

Encode audioBuffer to wave or mp3 from the browser, using an unified API

USAGE:

Import the library as script: (Copy the dist/audioEncoder.js file in your project)

<script src="audioEncoder.js" type="text/javascript"></script>

Or require as a module:

var audioEncoder = require('audio-encoder');

Encode an AudioBuffer instance:

audioEncoder(audioBuffer, encoding, onProgress, onComplete);

encoding is either:

• 'WAV' or 0 or null -> will encode to a wave file
• any valid mp3 bitrate: 320, 256, 192, 128, 96, 64, 56, 48, 40, 32

onComplete gets called with a Blob instance as result.

NOTE:

Bitrate lower that 96 will force audio to be MONO. On top of that, the sample rate will be degraded according to the following table:

bitrate	sample rate	force to mono
96 kBps and higher	44.1 kHz	false
64 kBps	44.1 kHz	true
56 kBps	32 kHz	true
48 kBps	32 kHz	true
40 kBps	24 kHz	true
32 kBps	22 kHz	true

Example

const audioEncoder = require('audio-encoder');
const fileSaver    = require('file-saver');

// create audioBuffer
const audioContext = new AudioContext();
const length = 44100; // one second @ 44.1KHz
const audioBuffer = audioContext.createBuffer(1, length, 44100);
const channelData = audioBuffer.getChannelData(0);

// fill some audio
for (let i = 0; i < length; i++) {
	channelData[i] = Math.sin(i * 0.03);
}

// convert as mp3 and save file using file-saver
audioEncoder(audioBuffer, 128, null, function onComplete(blob) {
	fileSaver.saveAs(blob, 'sound.mp3');
});