public final class TrackGroup


An immutable group of tracks available within a media stream. All tracks in a group present the same content, but their formats may differ.

As an example of how tracks can be grouped, consider an adaptive playback where a main video feed is provided in five resolutions, and an alternative video feed (e.g., a different camera angle in a sports match) is provided in two resolutions. In this case there will be two video track groups, one corresponding to the main video feed containing five tracks, and a second for the alternative video feed containing two tracks.

Note that audio tracks whose languages differ are not grouped, because content in different languages is not considered to be the same. Conversely, audio tracks in the same language that only differ in properties such as bitrate, sampling rate, channel count and so on can be grouped. This also applies to text tracks.

Note also that this class only contains information derived from the media itself. Unlike Tracks.Group, it does not include runtime information such as the extent to which playback of each track is supported by the device, or which tracks are currently selected.

Summary

Public fields

final String

An identifier for the track group.

final int

The number of tracks in the group.

final int

The type of tracks in the group.

Public constructors

@UnstableApi
TrackGroup(Format[] formats)

Constructs a track group containing the provided formats.

@UnstableApi
TrackGroup(String id, Format[] formats)

Constructs a track group with the provided id and formats.

Public methods

TrackGroup

Returns a copy of this track group with the specified id.

boolean
static TrackGroup

Restores a TrackGroup from a Bundle.

Format

Returns the format of the track at a given index.

int
int

Returns the index of the track with the given format in the group.

Bundle

Public fields

id

@UnstableApi
public final String id

An identifier for the track group.

length

@UnstableApi
public final int length

The number of tracks in the group.

type

@UnstableApi
@C.TrackType
public final int type

The type of tracks in the group.

Public constructors

TrackGroup

@UnstableApi
public TrackGroup(Format[] formats)

Constructs a track group containing the provided formats.

Parameters
Format[] formats

The list of Formats. Must not be empty.

TrackGroup

@UnstableApi
public TrackGroup(String id, Format[] formats)

Constructs a track group with the provided id and formats.

Parameters
String id

The identifier of the track group. May be an empty string.

Format[] formats

The list of Formats. Must not be empty.

Public methods

copyWithId

@UnstableApi
public TrackGroup copyWithId(String id)

Returns a copy of this track group with the specified id.

Parameters
String id

The identifier for the copy of the track group.

Returns
TrackGroup

The copied track group.

equals

public boolean equals(@Nullable Object obj)

fromBundle

@UnstableApi
public static TrackGroup fromBundle(Bundle bundle)

Restores a TrackGroup from a Bundle.

getFormat

@UnstableApi
public Format getFormat(int index)

Returns the format of the track at a given index.

Parameters
int index

The index of the track.

Returns
Format

The track's format.

hashCode

public int hashCode()

indexOf

@UnstableApi
public int indexOf(Format format)

Returns the index of the track with the given format in the group. The format is located by identity so, for example, group.indexOf(group.getFormat(index)) == index even if multiple tracks have formats that contain the same values.

Parameters
Format format

The format.

Returns
int

The index of the track, or INDEX_UNSET if no such track exists.

toBundle

@UnstableApi
public Bundle toBundle()