RTCEncodedAudioFrame: RTCEncodedAudioFrame() constructor

Baseline 2025

Newly available

Since November 2025, this feature works across the latest devices and browser versions. This feature might not work in older devices or browsers.

Note: This feature is available in Dedicated Web Workers.

The RTCEncodedAudioFrame() constructor creates a new and fully independent RTCEncodedAudioFrame object.

The new object is a deep clone of the original object data and metadata, with any metadata specified in the options parameter overwriting the copied values.

Syntax

js
new RTCEncodedAudioFrame(originalFrame);
new RTCEncodedAudioFrame(originalFrame, options);

Parameters

originalFrame

The frame to be copied.

options Optional

This is an object with the following property:

metadata Optional

An object setting the frame metadata. This is an object with the same properties as the object returned by RTCEncodedAudioFrame.getMetadata().

Exceptions

TypeError
- The source buffer is detached.
RangeError
- The allocation is too large.

Examples

Cloning a frame with modified metadata

This snippet shows how you might copy a frame and modify its metadata. In this case we just update the capture time.

js
// Frame is an incoming RTCEncodedAudioFrame
frame.getMetadata();

const newFrame = new RTCEncodedAudioFrame(frame, {
  metadata: {
    captureTime: frame.metadata.captureTime + 3,
  },
});

This kind of modification might be useful if you need to create multiple outgoing frames from a single incoming frame; for example, in order to relay media to another peer on the network. Generally you will not need to modify the metadata for a frame.