Interface ILocalAudioTrack

LocalAudioTrack is the basic interface for local audio tracks, providing main methods of local audio tracks.

You can create a local audio track by calling AgoraRTC.createCustomAudioTrack.

The following interfaces are inherited from LocalAudioTrack:

  • MicrophoneAudioTrack, the interface for the audio sampled by a local microphone, which adds several microphone-related functions.
  • BufferSourceAudioTrack, the interface for the audio from a local audio file, which adds several audio-file-related functions.





isPlaying: boolean

Whether a media track is playing on the webpage:

  • true: The media track is playing on the webpage.
  • false: The media track is not playing on the webpage.


trackMediaType: "audio" | "video"

The type of a media track:

  • "audio": Audio track.
  • "video": Video track.



  • close(): void
  • Closes a local track and releases the audio and video resources that it occupies.

    Once you close a local track, you can no longer reuse it.

    Returns void


  • getListeners(event: string): Function[]
  • Gets all the listeners for a specified event.


    • event: string

      The event name.

    Returns Function[]


  • getMediaStreamTrack(): MediaStreamTrack



  • getTrackId(): string
  • Gets the ID of a media track, a unique identifier generated by the SDK.

    Returns string

    The media track ID.


  • getTrackLabel(): string
  • Gets the label of a local track.

    Returns string

    The label that the SDK returns may include:

    • The MediaDeviceInfo.label property, if the track is created by calling createMicrophoneAudioTrack or createCameraVideoTrack.
    • The sourceId property, if the track is created by calling createScreenVideoTrack.
    • The MediaStreamTrack.label property, if the track is created by calling createCustomAudioTrack or createCustomVideoTrack.


  • getVolumeLevel(): number
  • Gets the audio level of a local audio track.

    Returns number

    The audio level. The value range is [0,1]. 1 is the highest audio level.


  • off(event: string, listener: Function): void
  • Removes the listener for a specified event.


    • event: string

      The event name.

    • listener: Function

      The callback that corresponds to the event listener.

    Returns void



  • once(event: string, listener: Function): void
  • Listens for a specified event once.

    When the specified event happens, the SDK triggers the callback that you pass and then removes the listener.


    • event: string

      The event name.

    • listener: Function

      The callback to trigger.

    Returns void


  • play(): void
  • Plays a local audio track.

    When playing a audio track, you do not need to pass any DOM element.

    Returns void


  • removeAllListeners(event?: undefined | string): void
  • Removes all listeners for a specified event.


    • Optional event: undefined | string

      The event name. If left empty, all listeners for all events are removed.

    Returns void


  • setAudioFrameCallback(audioFrameCallback: null | function, frameSize?: undefined | number): void
  • Sets the callback for getting raw audio data in PCM format.

    After you successfully set the callback, the SDK constantly returns the audio frames of a local audio track in this callback by using AudioBuffer.

    You can set the frameSize parameter to determine the frame size in each callback, which affects the interval between the callbacks. The larger the frame size, the longer the interval between them.

    track.setAudioFrameCallback((buffer) => {
      for (let channel = 0; channel < buffer.numberOfChannels; channel += 1) {
        // Float32Array with PCM data
        const currentChannelData = buffer.getChannelData(channel);
        console.log("PCM data in channel", channel, currentChannelData);
    }, 2048);
    // ....
    // Stop getting the raw audio data


    • audioFrameCallback: null | function

      The callback function for receiving the AudioBuffer object. If you set audioBufferCallback as null, the SDK stops getting raw audio data.

    • Optional frameSize: undefined | number

      The number of samples of each audio channel that an AudioBuffer object contains. You can set frameSize as 256, 512, 1024, 2048, 4096, 8192, or 16384. The default value is 4096.

    Returns void


  • setEnabled(enabled: boolean): Promise<void>
  • Since

    Enables/Disables the track.

    After a track is disabled, the SDK stops playing and publishing the track.


    • enabled: boolean

      Whether to enable the track:

      • true: Enable the track.
      • false: Disable the track.

    Returns Promise<void>


  • setPlaybackDevice(deviceId: string): Promise<void>
  • Since

    Sets the audio playback device, for example, the speaker.

    This method supports Chrome only. Other browsers throw a 'NOT_SUPPORTED error when calling this method.


    Returns Promise<void>


  • setVolume(volume: number): void
  • Sets the volume of a local audio track.


    • volume: number

      The volume. The value ranges from 0 (mute) to 1000 (maximum). A value of 100 is the original volume.

    Returns void


  • stop(): void
  • Stops playing the media track.

    Returns void