video.js HLS Source Handler

Play back HLS with video.js, even where it's not natively supported.

Getting Started

Download videojs-contrib-hls and include it in your page along with video.js:

<video id=example-video width=600 height=300 class="video-js vjs-default-skin" controls>
  <source
     src="https://example.com/index.m3u8"
     type="application/x-mpegURL">
</video>
<script src="video.js"></script>
<script src="videojs-hls.min.js"></script>
<script>
var player = videojs('example-video');
player.play();
</script>

Check out our live example if you're having trouble.

Documentation

HTTP Live Streaming (HLS) has become a de-facto standard for streaming video on mobile devices thanks to its native support on iOS and Android. There are a number of reasons independent of platform to recommend the format, though:

• Supports (client-driven) adaptive bitrate selection
• Delivered over standard HTTP ports
• Simple, text-based manifest format
• No proprietary streaming servers required

Unfortunately, all the major desktop browsers except for Safari are missing HLS support. That leaves web developers in the unfortunate position of having to maintain alternate renditions of the same video and potentially having to forego HTML-based video entirely to provide the best desktop viewing experience.

This project addresses that situation by providing a polyfill for HLS on browsers that have support for Media Source Extensions, or failing that, support Flash. You can deploy a single HLS stream, code against the regular HTML5 video APIs, and create a fast, high-quality video experience across all the big web device categories.

Check out the full documentation for details on how HLS works and advanced configuration. A description of the adaptive switching behavior is available, too.

videojs-contrib-hls support a bunch of HLS v2 and v3 features. Here are some highlights:

• video-on-demand and live playback modes
• backup or redundant streams
• mid-segment quality switching
• AES-128 segment encryption
• CEA-608 captions are automatically translated into standard HTML5 caption text tracks
• Timed ID3 Metadata is automatically translated into HTML5 metedata text tracks
• Highly customizable adaptive bitrate selection
• Automatic bandwidth tracking
• Cross-domain credentials support with CORS
• Tight integration with video.js and a philosophy of exposing as much as possible with standard HTML APIs

Options

You may pass in an options object to the hls source handler at player initialization. You can pass in options just like you would for other parts of video.js:

videojs(video, {
  hls: {
    withCredentials: true
  }
});

withCredentials

Type: boolean

When the withCredentials property is set to true, all XHR requests for manifests and segments would have withCredentials set to true as well. This enables storing and passing cookies from the server that the manifests and segments live on. This has some implications on CORS because when set, the Access-Control-Allow-Origin header cannot be set to *, also, the response headers require the addition of Access-Control-Allow-Credentials header which is set to true. See html5rocks's article for more info.

Runtime Properties

Runtime properties are attached to the tech object when HLS is in use. You can get a reference to the HLS source handler like this:

var hls = player.tech({ IWillNotUseThisInPlugins: true }).hls;

If you were thinking about modifying runtime properties in a video.js plugin, we'd recommend you avoid it. Your plugin won't work with videos that don't use videojs-contrib-hls and the best plugins work across all the media types that video.js supports. If you're deploying videojs-contrib-hls on your own website and want to make a couple tweaks though, go for it!

hls.playlists.master

Type: object

An object representing the parsed master playlist. If a media playlist is loaded directly, a master playlist with only one entry will be created.

hls.playlists.media

Type: function

A function that can be used to retrieve or modify the currently active media playlist. The active media playlist is referred to when additional video data needs to be downloaded. Calling this function with no arguments returns the parsed playlist object for the active media playlist. Calling this function with a playlist object from the master playlist or a URI string as specified in the master playlist will kick off an asynchronous load of the specified media playlist. Once it has been retreived, it will become the active media playlist.

hls.segmentXhrTime

Type: number

The number of milliseconds it took to download the last media segment. This value is updated after each segment download completes.

hls.bandwidth

Type: number

The number of bits downloaded per second in the last segment download. This value is used by the default implementation of selectPlaylist to select an appropriate bitrate to play.

Before the first video segment has been downloaded, it's hard to estimate bandwidth accurately. The HLS tech uses a heuristic based on the playlist download times to do this estimation by default. If you have a more accurate source of bandwidth information, you can override this value as soon as the HLS tech has loaded to provide an initial bandwidth estimate.

hls.bytesReceived

Type: number

The total number of content bytes downloaded by the HLS tech.

hls.selectPlaylist

Type: function

A function that returns the media playlist object to use to download the next segment. It is invoked by the tech immediately before a new segment is downloaded. You can override this function to provide your adaptive streaming logic. You must, however, be sure to return a valid media playlist object that is present in player.hls.master.

Events

Standard HTML video events are handled by video.js automatically and are triggered on the player object. In addition, there are a couple specialized events you can listen to on the HLS object during playback:

loadedmetadata

Fired after the first media playlist is downloaded for a stream.

loadedplaylist

Fired immediately after a new master or media playlist has been downloaded. By default, the tech only downloads playlists as they are needed.

mediachange

Fired when a new playlist becomes the active media playlist. Note that the actual rendering quality change does not occur simultaneously with this event; a new segment must be requested and the existing buffer depleted first.

In-Band Metadata

The HLS tech supports timed metadata embedded as ID3 tags. When a stream is encountered with embedded metadata, an in-band metadata text track will automatically be created and populated with cues as they are encountered in the stream. UTF-8 encoded TXXX and WXXX ID3 frames are mapped to cue points and their values set as the cue text. Cues are created for all other frame types and the data is attached to the generated cue:

cue.value.data

There are lots of guides and references to using text tracks around the web.

Hosting Considerations

Unlike a native HLS implementation, the HLS tech has to comply with the browser's security policies. That means that all the files that make up the stream must be served from the same domain as the page hosting the video player or from a server that has appropriate CORS headers configured. Easy instructions are available for popular webservers and most CDNs should have no trouble turning CORS on for your account.

Testing

For testing, you can either run npm test or use grunt directly. If you use npm test, it will only run the karma and end-to-end tests using chrome. You can specify which browsers you want the tests to run via grunt's test task. You can use either grunt-style arguments or comma separated arguments:

grunt test:chrome:firefox	# grunt-style
grunt test:chrome,firefox	# comma-separated

Possible options are:

• chromecanary
• phantomjs
• opera
• chrome¹
• safari^{1, 2}
• firefox¹
• ie¹

¹supported end-to-end browsers
²requires the SafariDriver extension to be installed

Release History

Check out the changelog for a summary of each release.