Interface TextTrackDescription

Describes the configuration of a side-loaded text track.

interface TextTrackDescription {
    default?: boolean;
    format?: string;
    kind?: string;
    label?: string;
    src: string;
    srclang?: string;


default?: boolean

Whether the text track should be enabled by default.


- Only one text track per TextTrack.kind may be marked as default.

Default Value


format?: string

The format of the track, represented by a value from the following list:
- 'srt'
- 'ttml'
- 'webvtt'
- 'emsg'
- 'eventstream'
- 'id3'
- 'cea608'
- 'daterange'

Default Value


kind?: string

The kind of the text track, represented by a value from the following list:
- 'subtitles': The track provides subtitles, used to display subtitles in a video.
- 'captions': The track provides a translation of dialogue and sound effects (suitable for users with a hearing impairment).
- 'descriptions': The track provides a textual description of the video (suitable for users with a vision impairment).
- 'chapters': The track provides chapter titles (suitable for navigating the media resource).
- 'metadata': The track provides content used by scripts and is not visible for users.


- If an unrecognized value is provided, the player will interpret it as 'metadata'.

Default Value


label?: string

A label for the text track.


- This will be used as an identifier on the player API and in the UI.

src: string

The source URL of the text track.

srclang?: string

The language of the text track.