media3/docs/hls.md
ibaker 1391b7c65d Remove references to Player(Control)View from the dev guide
Remove most of the customisation documentation, since StyledPlayerView
isn't really designed to be customised as deeply as PlayerView.

Also remove most documentation around StyledPlayerControlView,
especially as a standalone controller class - since it doesn't work
well for this use-case.

#minor-release

PiperOrigin-RevId: 426090762
2022-02-04 10:09:40 +00:00

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Markdown

---
title: HLS
---
{% include_relative _page_fragments/supported-formats-hls.md %}
## Using MediaItem ##
To play an HLS stream, you need to depend on the HLS module.
~~~
implementation 'com.google.android.exoplayer:exoplayer-hls:2.X.X'
~~~
{: .language-gradle}
You can then create a `MediaItem` for an HLS playlist URI and pass it to the
player.
~~~
// Create a player instance.
ExoPlayer player = new ExoPlayer.Builder(context).build();
// Set the media item to be played.
player.setMediaItem(MediaItem.fromUri(hlsUri));
// Prepare the player.
player.prepare();
~~~
{: .language-java}
If your URI doesn't end with `.m3u8`, you can pass `MimeTypes.APPLICATION_M3U8`
to `setMimeType` of `MediaItem.Builder` to explicitly indicate the type of the
content.
The URI of the media item may point to either a media playlist or a multivariant
playlist. If the URI points to a multivariant playlist that declares multiple
`#EXT-X-STREAM-INF` tags then ExoPlayer will automatically adapt between
variants, taking into account both available bandwidth and device capabilities.
## Using HlsMediaSource ##
For more customization options, you can create a `HlsMediaSource` and pass it
directly to the player instead of a `MediaItem`.
~~~
// Create a data source factory.
DataSource.Factory dataSourceFactory = new DefaultHttpDataSource.Factory();
// Create a HLS media source pointing to a playlist uri.
HlsMediaSource hlsMediaSource =
new HlsMediaSource.Factory(dataSourceFactory)
.createMediaSource(MediaItem.fromUri(hlsUri));
// Create a player instance.
ExoPlayer player = new ExoPlayer.Builder(context).build();
// Set the media source to be played.
player.setMediaSource(hlsMediaSource);
// Prepare the player.
player.prepare();
~~~
{: .language-java}
## Accessing the manifest ##
You can retrieve the current manifest by calling `Player.getCurrentManifest`.
For HLS you should cast the returned object to `HlsManifest`. The
`onTimelineChanged` callback of `Player.Listener` is also called whenever
the manifest is loaded. This will happen once for a on-demand content, and
possibly many times for live content. The code snippet below shows how an app
can do something whenever the manifest is loaded.
~~~
player.addListener(
new Player.Listener() {
@Override
public void onTimelineChanged(
Timeline timeline, @Player.TimelineChangeReason int reason) {
Object manifest = player.getCurrentManifest();
if (manifest != null) {
HlsManifest hlsManifest = (HlsManifest) manifest;
// Do something with the manifest.
}
}
});
~~~
{: .language-java}
## Customizing playback ##
ExoPlayer provides multiple ways for you to tailor playback experience to your
app's needs. See the [Customization page][] for examples.
### Disabling chunkless preparation ###
By default, ExoPlayer will use chunkless preparation. This means that ExoPlayer
will only use the information in the multivariant playlist to prepare the
stream, which works if the `#EXT-X-STREAM-INF` tags contain the `CODECS`
attribute.
You may need to disable this feature if your media segments contain muxed
closed-caption tracks that are not declared in the multivariant playlist with a
`#EXT-X-MEDIA:TYPE=CLOSED-CAPTIONS` tag. Otherwise, these closed-caption tracks
won't be detected and played. You can disable chunkless preparation in the
`HlsMediaSource.Factory` as shown in the following snippet. Note that this
will increase start up time as ExoPlayer needs to download a media segment to
discover these additional tracks and it is preferable to declare the
closed-caption tracks in the multivariant playlist instead.
~~~
HlsMediaSource hlsMediaSource =
new HlsMediaSource.Factory(dataSourceFactory)
.setAllowChunklessPreparation(false)
.createMediaSource(MediaItem.fromUri(hlsUri));
~~~
{: .language-java}
## Creating high quality HLS content ##
In order to get the most out of ExoPlayer, there are certain guidelines you can
follow to improve your HLS content. Read our [Medium post about HLS playback in
ExoPlayer][] for a full explanation. The main points are:
* Use precise segment durations.
* Use a continuous media stream; avoid changes in the media structure across
segments.
* Use the `#EXT-X-INDEPENDENT-SEGMENTS` tag.
* Prefer demuxed streams, as opposed to files that include both video and audio.
* Include all information you can in the Multivariant Playlist.
The following guidelines apply specifically for live streams:
* Use the `#EXT-X-PROGRAM-DATE-TIME` tag.
* Use the `#EXT-X-DISCONTINUITY-SEQUENCE` tag.
* Provide a long live window. One minute or more is great.
[HlsMediaSource]: {{ site.exo_sdk }}/source/hls/HlsMediaSource.html
[HTTP Live Streaming]: https://tools.ietf.org/html/rfc8216
[Customization page]: {{ site.baseurl }}/customization.html
[Medium post about HLS playback in ExoPlayer]: https://medium.com/google-exoplayer/hls-playback-in-exoplayer-a33959a47be7