index.md

---

title: AudioData
slug: Web/API/AudioData
page-type: web-api-interface
status:
  - experimental
browser-compat: api.AudioData

---

{{APIRef("WebCodecs API")}}{{SeeCompatTable}}

The AudioData interface of the WebCodecs API represents an audio sample.

AudioData is a transferable object.

Description

An audio track consists of a stream of audio samples, each sample representing a captured moment of sound. An AudioData object is a representation of such a sample. Working alongside the interfaces of the Insertable Streams API, you can break a stream into individual AudioData objects with {{domxref("MediaStreamTrackProcessor")}}, or construct an audio track from a stream of frames with {{domxref("MediaStreamTrackGenerator")}}.

Note: Find out more about audio on the web in Digital audio concepts.

The media resource

An AudioData object contains a reference to an attached media resource. This media resource contains the actual audio sample data described by the object. A media resource is maintained by the user agent until it is no longer referenced by an AudioData object, for example when {{domxref("AudioData.close()")}} is called.

Planes and audio format

To return the sample format of an AudioData use the {{domxref("AudioData.format")}} property. The format may be described as interleaved or planar. In interleaved formats, the audio samples from the different channels are laid out in a single buffer, described as a plane. This plane contains a number of elements equal to {{domxref("AudioData.numberOfFrames")}} * {{domxref("AudioData.numberOfChannels")}}.

In planar format, the number of planes is equal to {{domxref("AudioData.numberOfChannels")}}, and each plane is a buffer containing a number of elements equal to {{domxref("AudioData.numberOfFrames")}}.

Constructor

• {{domxref("AudioData.AudioData", "AudioData()")}} {{Experimental_Inline}}

  • : Creates a new AudioData object.

Instance properties

• {{domxref("AudioData.format")}} {{ReadOnlyInline}} {{Experimental_Inline}}

  • : Returns the sample format of the audio.

• {{domxref("AudioData.sampleRate")}} {{ReadOnlyInline}} {{Experimental_Inline}}

  • : Returns the sample rate of the audio in Hz.

• {{domxref("AudioData.numberOfFrames")}} {{ReadOnlyInline}} {{Experimental_Inline}}

  • : Returns the number of frames.

• {{domxref("AudioData.numberOfChannels")}} {{ReadOnlyInline}} {{Experimental_Inline}}

  • : Returns the number of audio channels.

• {{domxref("AudioData.duration")}} {{ReadOnlyInline}} {{Experimental_Inline}}

  • : Returns the duration of the audio in microseconds.

• {{domxref("AudioData.timestamp")}} {{ReadOnlyInline}} {{Experimental_Inline}}

  • : Returns the timestamp of the audio in microseconds.

Instance methods

• {{domxref("AudioData.allocationSize()")}} {{Experimental_Inline}}

  • : Returns the number of bytes required to hold the sample as filtered by options passed into the method.

• {{domxref("AudioData.copyTo()")}} {{Experimental_Inline}}

  • : Copies the samples from the specified plane of the AudioData object to the destination.

• {{domxref("AudioData.clone()")}} {{Experimental_Inline}}

  • : Creates a new AudioData object with reference to the same media resource as the original.

• {{domxref("AudioData.close()")}} {{Experimental_Inline}}

  • : Clears all states and releases the reference to the media resource.

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}