Java Code Examples for com.google.android.exoplayer2.source.TrackGroupArray#EMPTY

/**
 * Creates empty dummy playback info which can be used for masking as long as no real playback
 * info is available.
 *
 * @param startPositionUs The start position at which playback should start, in microseconds.
 * @param emptyTrackSelectorResult An empty track selector result with null entries for each
 *     renderer.
 * @return A dummy playback info.
 */
public static PlaybackInfo createDummy(
    long startPositionUs, TrackSelectorResult emptyTrackSelectorResult) {
  return new PlaybackInfo(
      Timeline.EMPTY,
      DUMMY_MEDIA_PERIOD_ID,
      startPositionUs,
      /* contentPositionUs= */ C.TIME_UNSET,
      Player.STATE_IDLE,
      /* playbackError= */ null,
      /* isLoading= */ false,
      TrackGroupArray.EMPTY,
      emptyTrackSelectorResult,
      DUMMY_MEDIA_PERIOD_ID,
      startPositionUs,
      /* totalBufferedDurationUs= */ 0,
      startPositionUs);
}
 

/**
 * Creates a new holder with information required to play it as part of a timeline.
 *
 * @param rendererCapabilities The renderer capabilities.
 * @param rendererPositionOffsetUs The renderer time of the start of the period, in microseconds.
 * @param trackSelector The track selector.
 * @param allocator The allocator.
 * @param mediaSource The media source that produced the media period.
 * @param info Information used to identify this media period in its timeline period.
 * @param emptyTrackSelectorResult A {@link TrackSelectorResult} with empty selections for each
 *     renderer.
 */
public MediaPeriodHolder(
    RendererCapabilities[] rendererCapabilities,
    long rendererPositionOffsetUs,
    TrackSelector trackSelector,
    Allocator allocator,
    MediaSource mediaSource,
    MediaPeriodInfo info,
    TrackSelectorResult emptyTrackSelectorResult) {
  this.rendererCapabilities = rendererCapabilities;
  this.rendererPositionOffsetUs = rendererPositionOffsetUs;
  this.trackSelector = trackSelector;
  this.mediaSource = mediaSource;
  this.uid = info.id.periodUid;
  this.info = info;
  this.trackGroups = TrackGroupArray.EMPTY;
  this.trackSelectorResult = emptyTrackSelectorResult;
  sampleStreams = new SampleStream[rendererCapabilities.length];
  mayRetainStreamFlags = new boolean[rendererCapabilities.length];
  mediaPeriod =
      createMediaPeriod(
          info.id, mediaSource, allocator, info.startPositionUs, info.endPositionUs);
}
 

/**
 * Constructs an instance. Must be called from a thread that has an associated {@link Looper}.
 *
 * @param renderers The {@link Renderer}s that will be used by the instance.
 * @param trackSelector The {@link TrackSelector} that will be used by the instance.
 * @param loadControl The {@link LoadControl} that will be used by the instance.
 */
@SuppressLint("HandlerLeak")
public ExoPlayerImpl(Renderer[] renderers, TrackSelector trackSelector, LoadControl loadControl) {
  Log.i(TAG, "Init " + ExoPlayerLibraryInfo.VERSION + " [" + Util.DEVICE_DEBUG_INFO + "]");
  Assertions.checkState(renderers.length > 0);
  this.renderers = Assertions.checkNotNull(renderers);
  this.trackSelector = Assertions.checkNotNull(trackSelector);
  this.playWhenReady = false;
  this.playbackState = STATE_IDLE;
  this.listeners = new CopyOnWriteArraySet<>();
  emptyTrackSelections = new TrackSelectionArray(new TrackSelection[renderers.length]);
  timeline = Timeline.EMPTY;
  window = new Timeline.Window();
  period = new Timeline.Period();
  trackGroups = TrackGroupArray.EMPTY;
  trackSelections = emptyTrackSelections;
  eventHandler = new Handler() {
    @Override
    public void handleMessage(Message msg) {
      ExoPlayerImpl.this.handleEvent(msg);
    }
  };
  playbackInfo = new ExoPlayerImplInternal.PlaybackInfo(0, 0);
  internalPlayer = new ExoPlayerImplInternal(renderers, trackSelector, loadControl, playWhenReady,
      eventHandler, playbackInfo, this);
}
 

/**
 * Creates empty dummy playback info which can be used for masking as long as no real playback
 * info is available.
 *
 * @param startPositionUs The start position at which playback should start, in microseconds.
 * @param emptyTrackSelectorResult An empty track selector result with null entries for each
 *     renderer.
 * @return A dummy playback info.
 */
public static PlaybackInfo createDummy(
    long startPositionUs, TrackSelectorResult emptyTrackSelectorResult) {
  return new PlaybackInfo(
      Timeline.EMPTY,
      /* manifest= */ null,
      DUMMY_MEDIA_PERIOD_ID,
      startPositionUs,
      /* contentPositionUs =*/ C.TIME_UNSET,
      Player.STATE_IDLE,
      /* isLoading= */ false,
      TrackGroupArray.EMPTY,
      emptyTrackSelectorResult,
      DUMMY_MEDIA_PERIOD_ID,
      startPositionUs,
      /* totalBufferedDurationUs= */ 0,
      startPositionUs);
}
 

private PlaybackInfo getResetPlaybackInfo(
    boolean resetPosition, boolean resetState, int playbackState) {
  if (resetPosition) {
    maskingWindowIndex = 0;
    maskingPeriodIndex = 0;
    maskingWindowPositionMs = 0;
  } else {
    maskingWindowIndex = getCurrentWindowIndex();
    maskingPeriodIndex = getCurrentPeriodIndex();
    maskingWindowPositionMs = getCurrentPosition();
  }
  return new PlaybackInfo(
      resetState ? Timeline.EMPTY : playbackInfo.timeline,
      resetState ? null : playbackInfo.manifest,
      playbackInfo.periodId,
      playbackInfo.startPositionUs,
      playbackInfo.contentPositionUs,
      playbackState,
      /* isLoading= */ false,
      resetState ? TrackGroupArray.EMPTY : playbackInfo.trackGroups,
      resetState ? emptyTrackSelectorResult : playbackInfo.trackSelectorResult,
      playbackInfo.periodId,
      playbackInfo.startPositionUs,
      /* totalBufferedDurationUs= */ 0,
      playbackInfo.startPositionUs);
}
 

@Override
public TrackGroupArray getTrackGroups(int periodIndex) {
  Assertions.checkNotNull(playlist);
  if (playlist instanceof HlsMediaPlaylist) {
    renditionGroups = new int[0];
    return TrackGroupArray.EMPTY;
  }
  // TODO: Generate track groups as in playback. Reverse the mapping in getDownloadAction.
  HlsMasterPlaylist masterPlaylist = (HlsMasterPlaylist) playlist;
  TrackGroup[] trackGroups = new TrackGroup[3];
  renditionGroups = new int[3];
  int trackGroupIndex = 0;
  if (!masterPlaylist.variants.isEmpty()) {
    renditionGroups[trackGroupIndex] = HlsMasterPlaylist.GROUP_INDEX_VARIANT;
    trackGroups[trackGroupIndex++] = new TrackGroup(toFormats(masterPlaylist.variants));
  }
  if (!masterPlaylist.audios.isEmpty()) {
    renditionGroups[trackGroupIndex] = HlsMasterPlaylist.GROUP_INDEX_AUDIO;
    trackGroups[trackGroupIndex++] = new TrackGroup(toFormats(masterPlaylist.audios));
  }
  if (!masterPlaylist.subtitles.isEmpty()) {
    renditionGroups[trackGroupIndex] = HlsMasterPlaylist.GROUP_INDEX_SUBTITLE;
    trackGroups[trackGroupIndex++] = new TrackGroup(toFormats(masterPlaylist.subtitles));
  }
  return new TrackGroupArray(Arrays.copyOf(trackGroups, trackGroupIndex));
}
 

/**
 * Creates empty dummy playback info which can be used for masking as long as no real playback
 * info is available.
 *
 * @param startPositionUs The start position at which playback should start, in microseconds.
 * @param emptyTrackSelectorResult An empty track selector result with null entries for each
 *     renderer.
 * @return A dummy playback info.
 */
public static PlaybackInfo createDummy(
    long startPositionUs, TrackSelectorResult emptyTrackSelectorResult) {
  return new PlaybackInfo(
      Timeline.EMPTY,
      /* manifest= */ null,
      DUMMY_MEDIA_PERIOD_ID,
      startPositionUs,
      /* contentPositionUs= */ C.TIME_UNSET,
      Player.STATE_IDLE,
      /* isLoading= */ false,
      TrackGroupArray.EMPTY,
      emptyTrackSelectorResult,
      DUMMY_MEDIA_PERIOD_ID,
      startPositionUs,
      /* totalBufferedDurationUs= */ 0,
      startPositionUs);
}
 

private PlaybackInfo getResetPlaybackInfo(
    boolean resetPosition, boolean resetState, int playbackState) {
  if (resetPosition) {
    maskingWindowIndex = 0;
    maskingPeriodIndex = 0;
    maskingWindowPositionMs = 0;
  } else {
    maskingWindowIndex = getCurrentWindowIndex();
    maskingPeriodIndex = getCurrentPeriodIndex();
    maskingWindowPositionMs = getCurrentPosition();
  }
  return new PlaybackInfo(
      resetState ? Timeline.EMPTY : playbackInfo.timeline,
      resetState ? null : playbackInfo.manifest,
      playbackInfo.periodId,
      playbackInfo.startPositionUs,
      playbackInfo.contentPositionUs,
      playbackState,
      /* isLoading= */ false,
      resetState ? TrackGroupArray.EMPTY : playbackInfo.trackGroups,
      resetState ? emptyTrackSelectorResult : playbackInfo.trackSelectorResult,
      playbackInfo.periodId,
      playbackInfo.startPositionUs,
      /* totalBufferedDurationUs= */ 0,
      playbackInfo.startPositionUs);
}
 

/**
 * Creates empty dummy playback info which can be used for masking as long as no real playback
 * info is available.
 *
 * @param startPositionUs The start position at which playback should start, in microseconds.
 * @param emptyTrackSelectorResult An empty track selector result with null entries for each
 *     renderer.
 * @return A dummy playback info.
 */
public static PlaybackInfo createDummy(
    long startPositionUs, TrackSelectorResult emptyTrackSelectorResult) {
  return new PlaybackInfo(
      Timeline.EMPTY,
      /* manifest= */ null,
      DUMMY_MEDIA_PERIOD_ID,
      startPositionUs,
      /* contentPositionUs =*/ C.TIME_UNSET,
      Player.STATE_IDLE,
      /* isLoading= */ false,
      TrackGroupArray.EMPTY,
      emptyTrackSelectorResult,
      DUMMY_MEDIA_PERIOD_ID,
      startPositionUs,
      /* totalBufferedDurationUs= */ 0,
      startPositionUs);
}
 

private PlaybackInfo getResetPlaybackInfo(
    boolean resetPosition, boolean resetState, int playbackState) {
  if (resetPosition) {
    maskingWindowIndex = 0;
    maskingPeriodIndex = 0;
    maskingWindowPositionMs = 0;
  } else {
    maskingWindowIndex = getCurrentWindowIndex();
    maskingPeriodIndex = getCurrentPeriodIndex();
    maskingWindowPositionMs = getCurrentPosition();
  }
  // Also reset period-based PlaybackInfo positions if resetting the state.
  resetPosition = resetPosition || resetState;
  MediaPeriodId mediaPeriodId =
      resetPosition
          ? playbackInfo.getDummyFirstMediaPeriodId(shuffleModeEnabled, window)
          : playbackInfo.periodId;
  long startPositionUs = resetPosition ? 0 : playbackInfo.positionUs;
  long contentPositionUs = resetPosition ? C.TIME_UNSET : playbackInfo.contentPositionUs;
  return new PlaybackInfo(
      resetState ? Timeline.EMPTY : playbackInfo.timeline,
      resetState ? null : playbackInfo.manifest,
      mediaPeriodId,
      startPositionUs,
      contentPositionUs,
      playbackState,
      /* isLoading= */ false,
      resetState ? TrackGroupArray.EMPTY : playbackInfo.trackGroups,
      resetState ? emptyTrackSelectorResult : playbackInfo.trackSelectorResult,
      mediaPeriodId,
      startPositionUs,
      /* totalBufferedDurationUs= */ 0,
      startPositionUs);
}
 

private PlaybackInfo getResetPlaybackInfo(
    boolean resetPosition,
    boolean resetState,
    boolean resetError,
    @State int playbackState) {
  if (resetPosition) {
    maskingWindowIndex = 0;
    maskingPeriodIndex = 0;
    maskingWindowPositionMs = 0;
  } else {
    maskingWindowIndex = getCurrentWindowIndex();
    maskingPeriodIndex = getCurrentPeriodIndex();
    maskingWindowPositionMs = getCurrentPosition();
  }
  // Also reset period-based PlaybackInfo positions if resetting the state.
  resetPosition = resetPosition || resetState;
  MediaPeriodId mediaPeriodId =
      resetPosition
          ? playbackInfo.getDummyFirstMediaPeriodId(shuffleModeEnabled, window, period)
          : playbackInfo.periodId;
  long startPositionUs = resetPosition ? 0 : playbackInfo.positionUs;
  long contentPositionUs = resetPosition ? C.TIME_UNSET : playbackInfo.contentPositionUs;
  return new PlaybackInfo(
      resetState ? Timeline.EMPTY : playbackInfo.timeline,
      mediaPeriodId,
      startPositionUs,
      contentPositionUs,
      playbackState,
      resetError ? null : playbackInfo.playbackError,
      /* isLoading= */ false,
      resetState ? TrackGroupArray.EMPTY : playbackInfo.trackGroups,
      resetState ? emptyTrackSelectorResult : playbackInfo.trackSelectorResult,
      mediaPeriodId,
      startPositionUs,
      /* totalBufferedDurationUs= */ 0,
      startPositionUs);
}
 

private PlaybackInfo getResetPlaybackInfo(
    boolean resetPosition, boolean resetState, int playbackState) {
  if (resetPosition) {
    maskingWindowIndex = 0;
    maskingPeriodIndex = 0;
    maskingWindowPositionMs = 0;
  } else {
    maskingWindowIndex = getCurrentWindowIndex();
    maskingPeriodIndex = getCurrentPeriodIndex();
    maskingWindowPositionMs = getCurrentPosition();
  }
  // Also reset period-based PlaybackInfo positions if resetting the state.
  resetPosition = resetPosition || resetState;
  MediaPeriodId mediaPeriodId =
      resetPosition
          ? playbackInfo.getDummyFirstMediaPeriodId(shuffleModeEnabled, window)
          : playbackInfo.periodId;
  long startPositionUs = resetPosition ? 0 : playbackInfo.positionUs;
  long contentPositionUs = resetPosition ? C.TIME_UNSET : playbackInfo.contentPositionUs;
  return new PlaybackInfo(
      resetState ? Timeline.EMPTY : playbackInfo.timeline,
      resetState ? null : playbackInfo.manifest,
      mediaPeriodId,
      startPositionUs,
      contentPositionUs,
      playbackState,
      /* isLoading= */ false,
      resetState ? TrackGroupArray.EMPTY : playbackInfo.trackGroups,
      resetState ? emptyTrackSelectorResult : playbackInfo.trackSelectorResult,
      mediaPeriodId,
      startPositionUs,
      /* totalBufferedDurationUs= */ 0,
      startPositionUs);
}
 

/**
 * Builds tracks that are exposed by this {@link HlsSampleStreamWrapper} instance, as well as
 * internal data-structures required for operation.
 *
 * <p>Tracks in HLS are complicated. A HLS master playlist contains a number of "variants". Each
 * variant stream typically contains muxed video, audio and (possibly) additional audio, metadata
 * and caption tracks. We wish to allow the user to select between an adaptive track that spans
 * all variants, as well as each individual variant. If multiple audio tracks are present within
 * each variant then we wish to allow the user to select between those also.
 *
 * <p>To do this, tracks are constructed as follows. The {@link HlsChunkSource} exposes (N+1)
 * tracks, where N is the number of variants defined in the HLS master playlist. These consist of
 * one adaptive track defined to span all variants and a track for each individual variant. The
 * adaptive track is initially selected. The extractor is then prepared to discover the tracks
 * inside of each variant stream. The two sets of tracks are then combined by this method to
 * create a third set, which is the set exposed by this {@link HlsSampleStreamWrapper}:
 *
 * <ul>
 *   <li>The extractor tracks are inspected to infer a "primary" track type. If a video track is
 *       present then it is always the primary type. If not, audio is the primary type if present.
 *       Else text is the primary type if present. Else there is no primary type.
 *   <li>If there is exactly one extractor track of the primary type, it's expanded into (N+1)
 *       exposed tracks, all of which correspond to the primary extractor track and each of which
 *       corresponds to a different chunk source track. Selecting one of these tracks has the
 *       effect of switching the selected track on the chunk source.
 *   <li>All other extractor tracks are exposed directly. Selecting one of these tracks has the
 *       effect of selecting an extractor track, leaving the selected track on the chunk source
 *       unchanged.
 * </ul>
 */
private void buildTracksFromSampleStreams() {
  // Iterate through the extractor tracks to discover the "primary" track type, and the index
  // of the single track of this type.
  int primaryExtractorTrackType = C.TRACK_TYPE_NONE;
  int primaryExtractorTrackIndex = C.INDEX_UNSET;
  int extractorTrackCount = sampleQueues.length;
  for (int i = 0; i < extractorTrackCount; i++) {
    String sampleMimeType = sampleQueues[i].getUpstreamFormat().sampleMimeType;
    int trackType;
    if (MimeTypes.isVideo(sampleMimeType)) {
      trackType = C.TRACK_TYPE_VIDEO;
    } else if (MimeTypes.isAudio(sampleMimeType)) {
      trackType = C.TRACK_TYPE_AUDIO;
    } else if (MimeTypes.isText(sampleMimeType)) {
      trackType = C.TRACK_TYPE_TEXT;
    } else {
      trackType = C.TRACK_TYPE_NONE;
    }
    if (getTrackTypeScore(trackType) > getTrackTypeScore(primaryExtractorTrackType)) {
      primaryExtractorTrackType = trackType;
      primaryExtractorTrackIndex = i;
    } else if (trackType == primaryExtractorTrackType
        && primaryExtractorTrackIndex != C.INDEX_UNSET) {
      // We have multiple tracks of the primary type. We only want an index if there only exists a
      // single track of the primary type, so unset the index again.
      primaryExtractorTrackIndex = C.INDEX_UNSET;
    }
  }

  TrackGroup chunkSourceTrackGroup = chunkSource.getTrackGroup();
  int chunkSourceTrackCount = chunkSourceTrackGroup.length;

  // Instantiate the necessary internal data-structures.
  primaryTrackGroupIndex = C.INDEX_UNSET;
  trackGroupToSampleQueueIndex = new int[extractorTrackCount];
  for (int i = 0; i < extractorTrackCount; i++) {
    trackGroupToSampleQueueIndex[i] = i;
  }

  // Construct the set of exposed track groups.
  TrackGroup[] trackGroups = new TrackGroup[extractorTrackCount];
  for (int i = 0; i < extractorTrackCount; i++) {
    Format sampleFormat = sampleQueues[i].getUpstreamFormat();
    if (i == primaryExtractorTrackIndex) {
      Format[] formats = new Format[chunkSourceTrackCount];
      if (chunkSourceTrackCount == 1) {
        formats[0] = sampleFormat.copyWithManifestFormatInfo(chunkSourceTrackGroup.getFormat(0));
      } else {
        for (int j = 0; j < chunkSourceTrackCount; j++) {
          formats[j] = deriveFormat(chunkSourceTrackGroup.getFormat(j), sampleFormat, true);
        }
      }
      trackGroups[i] = new TrackGroup(formats);
      primaryTrackGroupIndex = i;
    } else {
      Format trackFormat =
          primaryExtractorTrackType == C.TRACK_TYPE_VIDEO
                  && MimeTypes.isAudio(sampleFormat.sampleMimeType)
              ? muxedAudioFormat
              : null;
      trackGroups[i] = new TrackGroup(deriveFormat(trackFormat, sampleFormat, false));
    }
  }
  this.trackGroups = new TrackGroupArray(trackGroups);
  Assertions.checkState(optionalTrackGroups == null);
  optionalTrackGroups = TrackGroupArray.EMPTY;
}
 

@Override
public List<StreamKey> getStreamKeys(List<TrackSelection> trackSelections) {
  // See HlsMasterPlaylist.copy for interpretation of StreamKeys.
  HlsMasterPlaylist masterPlaylist = Assertions.checkNotNull(playlistTracker.getMasterPlaylist());
  boolean hasVariants = !masterPlaylist.variants.isEmpty();
  int audioWrapperOffset = hasVariants ? 1 : 0;
  // Subtitle sample stream wrappers are held last.
  int subtitleWrapperOffset = sampleStreamWrappers.length - masterPlaylist.subtitles.size();

  TrackGroupArray mainWrapperTrackGroups;
  int mainWrapperPrimaryGroupIndex;
  int[] mainWrapperVariantIndices;
  if (hasVariants) {
    HlsSampleStreamWrapper mainWrapper = sampleStreamWrappers[0];
    mainWrapperVariantIndices = manifestUrlIndicesPerWrapper[0];
    mainWrapperTrackGroups = mainWrapper.getTrackGroups();
    mainWrapperPrimaryGroupIndex = mainWrapper.getPrimaryTrackGroupIndex();
  } else {
    mainWrapperVariantIndices = new int[0];
    mainWrapperTrackGroups = TrackGroupArray.EMPTY;
    mainWrapperPrimaryGroupIndex = 0;
  }

  List<StreamKey> streamKeys = new ArrayList<>();
  boolean needsPrimaryTrackGroupSelection = false;
  boolean hasPrimaryTrackGroupSelection = false;
  for (TrackSelection trackSelection : trackSelections) {
    TrackGroup trackSelectionGroup = trackSelection.getTrackGroup();
    int mainWrapperTrackGroupIndex = mainWrapperTrackGroups.indexOf(trackSelectionGroup);
    if (mainWrapperTrackGroupIndex != C.INDEX_UNSET) {
      if (mainWrapperTrackGroupIndex == mainWrapperPrimaryGroupIndex) {
        // Primary group in main wrapper.
        hasPrimaryTrackGroupSelection = true;
        for (int i = 0; i < trackSelection.length(); i++) {
          int variantIndex = mainWrapperVariantIndices[trackSelection.getIndexInTrackGroup(i)];
          streamKeys.add(new StreamKey(HlsMasterPlaylist.GROUP_INDEX_VARIANT, variantIndex));
        }
      } else {
        // Embedded group in main wrapper.
        needsPrimaryTrackGroupSelection = true;
      }
    } else {
      // Audio or subtitle group.
      for (int i = audioWrapperOffset; i < sampleStreamWrappers.length; i++) {
        TrackGroupArray wrapperTrackGroups = sampleStreamWrappers[i].getTrackGroups();
        int selectedTrackGroupIndex = wrapperTrackGroups.indexOf(trackSelectionGroup);
        if (selectedTrackGroupIndex != C.INDEX_UNSET) {
          int groupIndexType =
              i < subtitleWrapperOffset
                  ? HlsMasterPlaylist.GROUP_INDEX_AUDIO
                  : HlsMasterPlaylist.GROUP_INDEX_SUBTITLE;
          int[] selectedWrapperUrlIndices = manifestUrlIndicesPerWrapper[i];
          for (int trackIndex = 0; trackIndex < trackSelection.length(); trackIndex++) {
            int renditionIndex =
                selectedWrapperUrlIndices[trackSelection.getIndexInTrackGroup(trackIndex)];
            streamKeys.add(new StreamKey(groupIndexType, renditionIndex));
          }
          break;
        }
      }
    }
  }
  if (needsPrimaryTrackGroupSelection && !hasPrimaryTrackGroupSelection) {
    // A track selection includes a variant-embedded track, but no variant is added yet. We use
    // the valid variant with the lowest bitrate to reduce overhead.
    int lowestBitrateIndex = mainWrapperVariantIndices[0];
    int lowestBitrate = masterPlaylist.variants.get(mainWrapperVariantIndices[0]).format.bitrate;
    for (int i = 1; i < mainWrapperVariantIndices.length; i++) {
      int variantBitrate =
          masterPlaylist.variants.get(mainWrapperVariantIndices[i]).format.bitrate;
      if (variantBitrate < lowestBitrate) {
        lowestBitrate = variantBitrate;
        lowestBitrateIndex = mainWrapperVariantIndices[i];
      }
    }
    streamKeys.add(new StreamKey(HlsMasterPlaylist.GROUP_INDEX_VARIANT, lowestBitrateIndex));
  }
  return streamKeys;
}
 

TrackGroupArray trackGroups(TrackType trackType, RendererTypeRequester rendererTypeRequester) {
    Optional<Integer> audioRendererIndex = rendererTrackIndexExtractor.extract(trackType, mappedTrackInfoLength(), rendererTypeRequester);
    return audioRendererIndex.isAbsent() ? TrackGroupArray.EMPTY : trackInfo().getTrackGroups(audioRendererIndex.get());
}
 

@Override
public TrackGroupArray getTrackGroups(int periodIndex) {
  return TrackGroupArray.EMPTY;
}
 

private void resetInternal(
    boolean releaseMediaSource, boolean resetPosition, boolean resetState) {
  handler.removeMessages(MSG_DO_SOME_WORK);
  rebuffering = false;
  mediaClock.stop();
  rendererPositionUs = 0;
  for (Renderer renderer : enabledRenderers) {
    try {
      disableRenderer(renderer);
    } catch (ExoPlaybackException | RuntimeException e) {
      // There's nothing we can do.
      Log.e(TAG, "Stop failed.", e);
    }
  }
  enabledRenderers = new Renderer[0];
  queue.clear(/* keepFrontPeriodUid= */ !resetPosition);
  setIsLoading(false);
  if (resetPosition) {
    pendingInitialSeekPosition = null;
  }
  if (resetState) {
    queue.setTimeline(Timeline.EMPTY);
    for (PendingMessageInfo pendingMessageInfo : pendingMessages) {
      pendingMessageInfo.message.markAsProcessed(/* isDelivered= */ false);
    }
    pendingMessages.clear();
    nextPendingMessageIndex = 0;
  }
  // Set the start position to TIME_UNSET so that a subsequent seek to 0 isn't ignored.
  MediaPeriodId mediaPeriodId = resetPosition ? getFirstMediaPeriodId() : playbackInfo.periodId;
  long startPositionUs = resetPosition ? C.TIME_UNSET : playbackInfo.positionUs;
  long contentPositionUs = resetPosition ? C.TIME_UNSET : playbackInfo.contentPositionUs;
  playbackInfo =
      new PlaybackInfo(
          resetState ? Timeline.EMPTY : playbackInfo.timeline,
          resetState ? null : playbackInfo.manifest,
          mediaPeriodId,
          startPositionUs,
          contentPositionUs,
          playbackInfo.playbackState,
          /* isLoading= */ false,
          resetState ? TrackGroupArray.EMPTY : playbackInfo.trackGroups,
          resetState ? emptyTrackSelectorResult : playbackInfo.trackSelectorResult,
          mediaPeriodId,
          startPositionUs,
          /* totalBufferedDurationUs= */ 0,
          startPositionUs);
  if (releaseMediaSource) {
    if (mediaSource != null) {
      mediaSource.releaseSource(/* listener= */ this);
      mediaSource = null;
    }
  }
}
 

/**
 * Builds tracks that are exposed by this {@link HlsSampleStreamWrapper} instance, as well as
 * internal data-structures required for operation.
 *
 * <p>Tracks in HLS are complicated. A HLS master playlist contains a number of "variants". Each
 * variant stream typically contains muxed video, audio and (possibly) additional audio, metadata
 * and caption tracks. We wish to allow the user to select between an adaptive track that spans
 * all variants, as well as each individual variant. If multiple audio tracks are present within
 * each variant then we wish to allow the user to select between those also.
 *
 * <p>To do this, tracks are constructed as follows. The {@link HlsChunkSource} exposes (N+1)
 * tracks, where N is the number of variants defined in the HLS master playlist. These consist of
 * one adaptive track defined to span all variants and a track for each individual variant. The
 * adaptive track is initially selected. The extractor is then prepared to discover the tracks
 * inside of each variant stream. The two sets of tracks are then combined by this method to
 * create a third set, which is the set exposed by this {@link HlsSampleStreamWrapper}:
 *
 * <ul>
 *   <li>The extractor tracks are inspected to infer a "primary" track type. If a video track is
 *       present then it is always the primary type. If not, audio is the primary type if present.
 *       Else text is the primary type if present. Else there is no primary type.
 *   <li>If there is exactly one extractor track of the primary type, it's expanded into (N+1)
 *       exposed tracks, all of which correspond to the primary extractor track and each of which
 *       corresponds to a different chunk source track. Selecting one of these tracks has the
 *       effect of switching the selected track on the chunk source.
 *   <li>All other extractor tracks are exposed directly. Selecting one of these tracks has the
 *       effect of selecting an extractor track, leaving the selected track on the chunk source
 *       unchanged.
 * </ul>
 */
private void buildTracksFromSampleStreams() {
  // Iterate through the extractor tracks to discover the "primary" track type, and the index
  // of the single track of this type.
  int primaryExtractorTrackType = C.TRACK_TYPE_NONE;
  int primaryExtractorTrackIndex = C.INDEX_UNSET;
  int extractorTrackCount = sampleQueues.length;
  for (int i = 0; i < extractorTrackCount; i++) {
    String sampleMimeType = sampleQueues[i].getUpstreamFormat().sampleMimeType;
    int trackType;
    if (MimeTypes.isVideo(sampleMimeType)) {
      trackType = C.TRACK_TYPE_VIDEO;
    } else if (MimeTypes.isAudio(sampleMimeType)) {
      trackType = C.TRACK_TYPE_AUDIO;
    } else if (MimeTypes.isText(sampleMimeType)) {
      trackType = C.TRACK_TYPE_TEXT;
    } else {
      trackType = C.TRACK_TYPE_NONE;
    }
    if (getTrackTypeScore(trackType) > getTrackTypeScore(primaryExtractorTrackType)) {
      primaryExtractorTrackType = trackType;
      primaryExtractorTrackIndex = i;
    } else if (trackType == primaryExtractorTrackType
        && primaryExtractorTrackIndex != C.INDEX_UNSET) {
      // We have multiple tracks of the primary type. We only want an index if there only exists a
      // single track of the primary type, so unset the index again.
      primaryExtractorTrackIndex = C.INDEX_UNSET;
    }
  }

  TrackGroup chunkSourceTrackGroup = chunkSource.getTrackGroup();
  int chunkSourceTrackCount = chunkSourceTrackGroup.length;

  // Instantiate the necessary internal data-structures.
  primaryTrackGroupIndex = C.INDEX_UNSET;
  trackGroupToSampleQueueIndex = new int[extractorTrackCount];
  for (int i = 0; i < extractorTrackCount; i++) {
    trackGroupToSampleQueueIndex[i] = i;
  }

  // Construct the set of exposed track groups.
  TrackGroup[] trackGroups = new TrackGroup[extractorTrackCount];
  for (int i = 0; i < extractorTrackCount; i++) {
    Format sampleFormat = sampleQueues[i].getUpstreamFormat();
    if (i == primaryExtractorTrackIndex) {
      Format[] formats = new Format[chunkSourceTrackCount];
      if (chunkSourceTrackCount == 1) {
        formats[0] = sampleFormat.copyWithManifestFormatInfo(chunkSourceTrackGroup.getFormat(0));
      } else {
        for (int j = 0; j < chunkSourceTrackCount; j++) {
          formats[j] = deriveFormat(chunkSourceTrackGroup.getFormat(j), sampleFormat, true);
        }
      }
      trackGroups[i] = new TrackGroup(formats);
      primaryTrackGroupIndex = i;
    } else {
      Format trackFormat =
          primaryExtractorTrackType == C.TRACK_TYPE_VIDEO
                  && MimeTypes.isAudio(sampleFormat.sampleMimeType)
              ? muxedAudioFormat
              : null;
      trackGroups[i] = new TrackGroup(deriveFormat(trackFormat, sampleFormat, false));
    }
  }
  this.trackGroups = new TrackGroupArray(trackGroups);
  Assertions.checkState(optionalTrackGroups == null);
  optionalTrackGroups = TrackGroupArray.EMPTY;
}
 

@Override
public List<StreamKey> getStreamKeys(List<TrackSelection> trackSelections) {
  // See HlsMasterPlaylist.copy for interpretation of StreamKeys.
  HlsMasterPlaylist masterPlaylist = Assertions.checkNotNull(playlistTracker.getMasterPlaylist());
  boolean hasVariants = !masterPlaylist.variants.isEmpty();
  int audioWrapperOffset = hasVariants ? 1 : 0;
  // Subtitle sample stream wrappers are held last.
  int subtitleWrapperOffset = sampleStreamWrappers.length - masterPlaylist.subtitles.size();

  TrackGroupArray mainWrapperTrackGroups;
  int mainWrapperPrimaryGroupIndex;
  int[] mainWrapperVariantIndices;
  if (hasVariants) {
    HlsSampleStreamWrapper mainWrapper = sampleStreamWrappers[0];
    mainWrapperVariantIndices = manifestUrlIndicesPerWrapper[0];
    mainWrapperTrackGroups = mainWrapper.getTrackGroups();
    mainWrapperPrimaryGroupIndex = mainWrapper.getPrimaryTrackGroupIndex();
  } else {
    mainWrapperVariantIndices = new int[0];
    mainWrapperTrackGroups = TrackGroupArray.EMPTY;
    mainWrapperPrimaryGroupIndex = 0;
  }

  List<StreamKey> streamKeys = new ArrayList<>();
  boolean needsPrimaryTrackGroupSelection = false;
  boolean hasPrimaryTrackGroupSelection = false;
  for (TrackSelection trackSelection : trackSelections) {
    TrackGroup trackSelectionGroup = trackSelection.getTrackGroup();
    int mainWrapperTrackGroupIndex = mainWrapperTrackGroups.indexOf(trackSelectionGroup);
    if (mainWrapperTrackGroupIndex != C.INDEX_UNSET) {
      if (mainWrapperTrackGroupIndex == mainWrapperPrimaryGroupIndex) {
        // Primary group in main wrapper.
        hasPrimaryTrackGroupSelection = true;
        for (int i = 0; i < trackSelection.length(); i++) {
          int variantIndex = mainWrapperVariantIndices[trackSelection.getIndexInTrackGroup(i)];
          streamKeys.add(new StreamKey(HlsMasterPlaylist.GROUP_INDEX_VARIANT, variantIndex));
        }
      } else {
        // Embedded group in main wrapper.
        needsPrimaryTrackGroupSelection = true;
      }
    } else {
      // Audio or subtitle group.
      for (int i = audioWrapperOffset; i < sampleStreamWrappers.length; i++) {
        TrackGroupArray wrapperTrackGroups = sampleStreamWrappers[i].getTrackGroups();
        int selectedTrackGroupIndex = wrapperTrackGroups.indexOf(trackSelectionGroup);
        if (selectedTrackGroupIndex != C.INDEX_UNSET) {
          int groupIndexType =
              i < subtitleWrapperOffset
                  ? HlsMasterPlaylist.GROUP_INDEX_AUDIO
                  : HlsMasterPlaylist.GROUP_INDEX_SUBTITLE;
          int[] selectedWrapperUrlIndices = manifestUrlIndicesPerWrapper[i];
          for (int trackIndex = 0; trackIndex < trackSelection.length(); trackIndex++) {
            int renditionIndex =
                selectedWrapperUrlIndices[trackSelection.getIndexInTrackGroup(trackIndex)];
            streamKeys.add(new StreamKey(groupIndexType, renditionIndex));
          }
          break;
        }
      }
    }
  }
  if (needsPrimaryTrackGroupSelection && !hasPrimaryTrackGroupSelection) {
    // A track selection includes a variant-embedded track, but no variant is added yet. We use
    // the valid variant with the lowest bitrate to reduce overhead.
    int lowestBitrateIndex = mainWrapperVariantIndices[0];
    int lowestBitrate = masterPlaylist.variants.get(mainWrapperVariantIndices[0]).format.bitrate;
    for (int i = 1; i < mainWrapperVariantIndices.length; i++) {
      int variantBitrate =
          masterPlaylist.variants.get(mainWrapperVariantIndices[i]).format.bitrate;
      if (variantBitrate < lowestBitrate) {
        lowestBitrate = variantBitrate;
        lowestBitrateIndex = mainWrapperVariantIndices[i];
      }
    }
    streamKeys.add(new StreamKey(HlsMasterPlaylist.GROUP_INDEX_VARIANT, lowestBitrateIndex));
  }
  return streamKeys;
}
 

private void resetInternal(
    boolean releaseMediaSource, boolean resetPosition, boolean resetState) {
  handler.removeMessages(MSG_DO_SOME_WORK);
  rebuffering = false;
  mediaClock.stop();
  rendererPositionUs = 0;
  for (Renderer renderer : enabledRenderers) {
    try {
      disableRenderer(renderer);
    } catch (ExoPlaybackException | RuntimeException e) {
      // There's nothing we can do.
      Log.e(TAG, "Stop failed.", e);
    }
  }
  enabledRenderers = new Renderer[0];
  queue.clear(/* keepFrontPeriodUid= */ !resetPosition);
  setIsLoading(false);
  if (resetPosition) {
    pendingInitialSeekPosition = null;
  }
  if (resetState) {
    queue.setTimeline(Timeline.EMPTY);
    for (PendingMessageInfo pendingMessageInfo : pendingMessages) {
      pendingMessageInfo.message.markAsProcessed(/* isDelivered= */ false);
    }
    pendingMessages.clear();
    nextPendingMessageIndex = 0;
  }
  // Set the start position to TIME_UNSET so that a subsequent seek to 0 isn't ignored.
  MediaPeriodId mediaPeriodId = resetPosition ? getFirstMediaPeriodId() : playbackInfo.periodId;
  long startPositionUs = resetPosition ? C.TIME_UNSET : playbackInfo.positionUs;
  long contentPositionUs = resetPosition ? C.TIME_UNSET : playbackInfo.contentPositionUs;
  playbackInfo =
      new PlaybackInfo(
          resetState ? Timeline.EMPTY : playbackInfo.timeline,
          resetState ? null : playbackInfo.manifest,
          mediaPeriodId,
          startPositionUs,
          contentPositionUs,
          playbackInfo.playbackState,
          /* isLoading= */ false,
          resetState ? TrackGroupArray.EMPTY : playbackInfo.trackGroups,
          resetState ? emptyTrackSelectorResult : playbackInfo.trackSelectorResult,
          mediaPeriodId,
          startPositionUs,
          /* totalBufferedDurationUs= */ 0,
          startPositionUs);
  if (releaseMediaSource) {
    if (mediaSource != null) {
      mediaSource.releaseSource(/* listener= */ this);
      mediaSource = null;
    }
  }
}