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VTTCue

The VTTCue interface—part of the API for handling WebVTT (text tracks on media presentations)—describes and controls the text track associated with a particular <track> element.

Constructor

VTTCue(): Returns a newly created VTTCue object that covers the given time range and has the given text.

Instance properties

This interface also inherits properties from TextTrackCue.

VTTCue.region: A VTTRegion object describing the video's sub-region that the cue will be drawn onto, or null if none is assigned.
VTTCue.vertical: Returns an enum representing the cue writing direction.
VTTCue.snapToLines: Returns true if the VTTCue.line attribute is an integer number of lines or a percentage of the video size.
VTTCue.line: Returns the line positioning of the cue. This can be the string auto or a number whose interpretation depends on the value of VTTCue.snapToLines.
VTTCue.lineAlign: Returns an enum representing the alignment of the VTTCue.line.
VTTCue.position: Returns the indentation of the cue within the line. This can be the string auto or a number representing the percentage of the VTTCue.region, or the video size if VTTCue.region is null.
VTTCue.positionAlign: Returns an enum representing the alignment of the cue. This is used to determine what the VTTCue.position is anchored to. The default is auto.
VTTCue.size: Returns a double representing the size of the cue, as a percentage of the video size.
VTTCue.align: Returns an enum representing the alignment of all the lines of text within the cue box.
VTTCue.text: Returns a string with the contents of the cue.

Instance methods

getCueAsHTML(): Returns the cue text as a DocumentFragment.

Example

HTML

The following example adds a new TextTrack to the video, then adds cues using the TextTrack.addCue() method, with a VTTCue object as the value.

html

<video
  controls
  src="https://interactive-examples.mdn.mozilla.net/media/cc0-videos/friday.mp4"></video>

CSS

css

video {
  width: 420px;
  height: 300px;
}

JavaScript

let video = document.querySelector("video");
let track = video.addTextTrack("captions", "Captions", "en");
track.mode = "showing";
track.addCue(new VTTCue(0, 0.9, "Hildy!"));
track.addCue(new VTTCue(1, 1.4, "How are you?"));
track.addCue(new VTTCue(1.5, 2.9, "Tell me, is the lord of the universe in?"));
track.addCue(new VTTCue(3, 4.2, "Yes, he's in - in a bad humor"));
track.addCue(new VTTCue(4.3, 6, "Somebody must've stolen the crown jewels"));
console.log(track.cues);

Result

Specifications

Specification
WebVTT: The Web Video Text Tracks Format # the-vttcue-interface

Browser compatibility

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	WebView Android	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet
`VTTCue`	33	79	31	No	20	8	4.4.3	33	31	20	8	2.0
`VTTCue`	23	12	31	10	≤12.1	6	4.4	25	31	≤12.1	8	1.5
`align`	23	79	31	No	≤12.1	6	4.4	25	31	≤12.1	8	1.5
`getCueAsHTML`	23	12	31	10	≤12.1	6	4.4	25	31	≤12.1	8	1.5
`line`	23	79	31	No	≤12.1	6	4.4	25	31	≤12.1	8	1.5
`lineAlign`	No	No	31	No	No	14.1	No	No	31	No	14.5	No
`position`	23	79	31	No	≤12.1	6	4.4	25	31	≤12.1	8	1.5
`positionAlign`	No	No	31	No	No	14.1	No	No	31	No	14.5	No
`region`	No	No	59	No	No	14.1	No	No	59	No	14.5	No
`size`	23	79	31	No	≤12.1	6	4.4	25	31	≤12.1	8	1.5
`snapToLines`	23	79	31	No	≤12.1	6	4.4	25	31	≤12.1	8	1.5
`text`	23	12	31	10	≤12.1	6	4.4	25	31	≤12.1	8	1.5
`vertical`	23	79	31	No	15	6	4.4	25	31	14	8	1.5

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/VTTCue