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video.js/docs/guides/setup.md

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Video.js Setup

Table of Contents

Getting Video.js

Video.js is officially available via CDN and npm.

Video.js works out of the box with not only HTML <script> and <link> tags, but also all major bundlers/packagers/builders, such as Browserify, Node, WebPack, etc.

Please refer to the Getting Started document for details.

Creating a Player

Note: Video.js works with <video> and <audio> elements, but for simplicity we'll refer only to <video> elements going forward.

Once you have Video.js loaded on your page, you're ready to create a player!

The core strength of Video.js is that it decorates a standard <video> element and emulates its associated events and APIs, while providing a customizable DOM-based UI.

Video.js supports all attributes of the <video> element (such as controls, preload, etc), but it also supports its own options. There are two ways to create a Video.js player and pass it options, but they both start with a standard <video> element with the attribute class="video-js":

<video class="video-js">
  <source src="//vjs.zencdn.net/v/oceans.mp4" type="video/mp4">
  <source src="//vjs.zencdn.net/v/oceans.webm" type="video/webm">
</video>

You can use a <video-js> element instead of <video>. Using a <video> element is undesirable in some circumstances, as the browser may show unstyled controls or try to load a source in the moments before the player initialises, which does not happen with the <video-js> custom element.

<video-js>
  <source src="//vjs.zencdn.net/v/oceans.mp4" type="video/mp4">
  <source src="//vjs.zencdn.net/v/oceans.webm" type="video/webm">
</video-js>

For a high-level overview of all the various embed options, check out the embeds page, then follow the rest of this page.

Automatic Setup

By default, when your web page finishes loading, Video.js will scan for media elements that have the data-setup attribute. The data-setup attribute is used to pass options to Video.js. A minimal example looks like this:

<video class="video-js" data-setup='{}'>
  <source src="//vjs.zencdn.net/v/oceans.mp4" type="video/mp4">
  <source src="//vjs.zencdn.net/v/oceans.webm" type="video/webm">
</video>

Note: You must use single-quotes with data-setup as it is expected to contain JSON.

Manual Setup

On the modern web, a <video> element often does not exist when the page finishes loading. In these cases, automatic setup is not possible, but manual setup is available via the videojs function.

One way to call this function is by providing it a string matching a <video> element's id attribute:

<video id="my-player" class="video-js">
  <source src="//vjs.zencdn.net/v/oceans.mp4" type="video/mp4">
  <source src="//vjs.zencdn.net/v/oceans.webm" type="video/webm">
</video>
videojs('my-player');

However, using an id attribute isn't always practical; so, the videojs function accepts a DOM element instead:

<video class="video-js">
  <source src="//vjs.zencdn.net/v/oceans.mp4" type="video/mp4">
  <source src="//vjs.zencdn.net/v/oceans.webm" type="video/webm">
</video>
videojs(document.querySelector('.video-js'));

Getting References to Players

Once players are created, Video.js keeps track of them internally. There are a few ways to get references to pre-existing players.

Using videojs

Calling videojs() with the ID of element of an already-existing player will return that player and will not create another one.

If there is no player matching the argument, it will attempt to create one.

Using videojs.getPlayer()

Sometimes, you want to get a reference to a player without the potential side effects of calling videojs(). This can be acheived by calling videojs.getPlayer() with either a string matching the element's ID or the element itself.

Using videojs.getPlayers() or videojs.players

The videojs.players property exposes all known players. The method, videojs.getPlayers() simply returns the same object.

Players are stored on this object with keys matching their IDs.

Note: A player created from an element without an ID will be assigned an automatically-generated ID.

Options

Note: This guide only covers how to pass options during player setup. For a complete reference on all available options, see the options guide.

There are three ways to pass options to Video.js. Because Video.js decorates an HTML5 <video> element, many of the options available are also available as standard <video> tag attributes:

<video controls autoplay preload="auto" ...>

Alternatively, you can use the data-setup attribute to pass options as JSON. This is also how you would set options that aren't standard to the <video> element:

<video data-setup='{"controls": true, "autoplay": false, "preload": "auto"}'...>

Note: You must use single-quotes around the value of data-setup as it contains a JSON string which must use double quotes.

Finally, if you're not using the data-setup attribute to trigger the player setup, you can pass in an object of player options as the second argument to the videojs function:

videojs('my-player', {
  controls: true,
  autoplay: false,
  preload: 'auto'
});

Note: Do not use both data-setup and an options object.

Global Defaults

Default options for all players can be found at videojs.options and can be changed directly. For example, to set {autoplay: true} for all future players:

videojs.options.autoplay = true;

A Note on <video> Tag Attributes

Many attributes are so-called boolean attributes. This means they are either on or off. In these cases, the attribute should have no value (or should have its name as its value) - its presence implies a true value and its absence implies a false value.

These are incorrect:

<video controls="true" ...>
<video loop="true" ...>
<video controls="false" ...>

Note: The example with controls="false" can be a point of confusion for new developers - it will actually turn controls on!

These are correct:

<video controls ...>
<video loop="loop" ...>
<video ...>

Player Readiness

Because Video.js techs have the potential to be loaded asynchronously, it isn't always safe to interact with a player immediately upon setup. For this reason, Video.js players have a concept of "readiness" which will be familiar to anyone who has used jQuery before.

Essentially, any number of ready callbacks can be defined for a Video.js player. There are three ways to pass these callbacks. In each example, we'll add an identical class to the player:

Pass a callback to the videojs() function as a third argument:

// Passing `null` for the options argument.
videojs('my-player', null, function() {
  this.addClass('my-example');
});

Pass a callback to a player's ready() method:

var player = videojs('my-player');

player.ready(function() {
  this.addClass('my-example');
});

Listen for the player's "ready" event:

var player = videojs('my-player');

player.on('ready', function() {
  this.addClass('my-example');
});

In each case, the callback is called asynchronously.

An important distinction between the above methods is that adding an listener for ready with on() must be done before the player is ready. With player.ready(), the function is called immediately if the player is already ready.

Advanced Player Workflows

For a discussion of more advanced player workflows, see the player workflows guide.