HTMLMedia​Element​.textTracks

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The read-only textTracks property on HTMLMediaElement objects returns a TextTrackList object listing all of the TextTrack objects representing the media element's text tracks, in the same order as in the list of text tracks.

You can detect when tracks are added to and removed from an <audio> or <video> element using the addtrack and removetrack events. However, these events aren't sent directly to the media element itself. Instead, they're sent to the track list object of the HTMLMediaElement that corresponds to the type of track that was added to the element

The returned list is live; that is, as tracks are added to and removed from the media element, the list's contents change dynamically. Once you have a reference to the list, you can monitor it for changes to detect when new text tracks are added or existing ones removed.

Syntax

var textTracks = mediaElement.textTracks;

Value

A TextTrackList object representing the list of text tracks included in the media element. The list of tracks can be accessed using array notation, or using the object's getTrackById() method.

Each track is represented by a TextTrack object which provides information about the track.

Examples

We start with a <video> that has several <track> children 

<video controls poster="/images/sample.gif"> 
  <source src="sample.mp4" type="video/mp4"> 
  <source src="sample.ogv" type="video/ogv"> 
  <track kind="captions" src="sampleCaptions.vtt" srclang="en"> 
  <track kind="descriptions" src="sampleDescriptions.vtt" srclang="en"> 
  <track kind="chapters" src="sampleChapters.vtt" srclang="en"> 
  <track kind="subtitles" src="sampleSubtitles_de.vtt" srclang="de"> 
  <track kind="subtitles" src="sampleSubtitles_en.vtt" srclang="en"> 
  <track kind="subtitles" src="sampleSubtitles_ja.vtt" srclang="ja"> 
  <track kind="subtitles" src="sampleSubtitles_oz.vtt" srclang="oz"> 
  <track kind="metadata" src="keyStage1.vtt" srclang="en" label="Key Stage 1"> 
  <track kind="metadata" src="keyStage2.vtt" srclang="en" label="Key Stage 2"> 
  <track kind="metadata" src="keyStage3.vtt" srclang="en" label="Key Stage 3"> 
</video>

The HTMLMediaElement.textTracks returns a textTracksList thru which we can iterate.  Here we print all the properties of each English track to the console.

var tracks = document.querySelector('video').textTracks; 

for (var i = 0, L = tracks.length; i < L; i++) { /* tracks.length == 10 */
   if (tracks[i].language == 'en') {
      console.dir(tracks[i]);
   }
}

Properties & Methods

properties

length
Returns the number of text tracks in TextTrackList object.

methods

getTrackById()
The getTrackById(id) method returns the first TextTrack in the TextTrackList object that matches the id, or null if there is no match.

Specifications

Specification Status Comment
HTML Living Standard
The definition of 'HTMLMediaElement.textTracks' in that specification.
Living Standard No change from HTML5
HTML5
The definition of 'HTMLMediaElement.textTracks' in that specification.
Recommendation Initial definition.

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
textTracksChrome Full support YesEdge Full support 12Firefox Full support YesIE ? Opera Full support YesSafari Full support YesWebView Android ? Chrome Android ? Firefox Android ? Opera Android ? Safari iOS ? Samsung Internet Android ?

Legend

Full support  
Full support
Compatibility unknown  
Compatibility unknown

See also