EncodedAudioChunk: EncodedAudioChunk() constructor

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

Note: This feature is available in Dedicated Web Workers.

The EncodedAudioChunk() constructor creates a new EncodedAudioChunk object representing a chunk of encoded audio.

Syntax

js
new EncodedAudioChunk(options)

Parameters

options

An object containing the following members:

type

Indicates if the chunk is a key chunk that does not rely on other frames for encoding. One of:

"key"

The data is a key chunk.

"delta"

The data is not a key chunk.

timestamp

An integer representing the timestamp of the audio in microseconds.

duration

An integer representing the length of the audio in microseconds.

data

An ArrayBuffer, a TypedArray, or a DataView containing the audio data.

transfer

An array of ArrayBuffers that EncodedAudioChunk will detach and take ownership of. If the array contains the ArrayBuffer backing data, EncodedAudioChunk will use that buffer directly instead of copying from it.

Examples

In the following example a new EncodedAudioChunk is created.

js
const init = {
  type: "key",
  data: audioBuffer,
  timestamp: 23000000,
  duration: 2000000,
  transfer: [audioBuffer],
};
chunk = new EncodedAudioChunk(init);

Specifications

Specification
WebCodecs
# dom-encodedaudiochunk-encodedaudiochunk

Browser compatibility

desktop mobile
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
EncodedAudioChunk() constructor
Chrome – Full support
Chrome 94 (Release date: 2021-09-21)
footnote Full support
Edge – Full support
Edge 94 (Release date: 2021-09-24)
footnote Full support
Firefox – Full support
Firefox 130 (Release date: 2024-09-03)
footnote Full support
Opera – Full support
Opera 80 (Release date: 2021-10-05)
footnote Full support
Safari – Full support
Safari 26 (Release date: 2025-09-15)
footnote Full support
Chrome Android – Full support
Chrome Android 94 (Release date: 2021-09-21)
footnote Full support
Firefox for Android – No support
Firefox for Android
footnote No support
Opera Android – Full support
Opera Android 66 (Release date: 2021-12-15)
footnote Full support
Safari on iOS – Full support
Safari on iOS 26 (Release date: 2025-09-15)
footnote Full support
Samsung Internet – Full support
Samsung Internet 17 (Release date: 2022-05-04)
footnote Full support
WebView Android – Full support
WebView Android 94 (Release date: 2021-09-21)
footnote Full support
WebView on iOS – Full support
WebView on iOS 26 (Release date: 2025-09-15)
footnote Full support

Legend

Tip: you can click/tap on a cell for more information.

Full support
Full support
No support
No support