com.google.android.exoplayer2.source.chunk.ChunkExtractorWrapper Java Examples

/**
 * @param manifestLoaderErrorThrower Throws errors affecting loading of manifests.
 * @param manifest The initial manifest.
 * @param elementIndex The index of the stream element in the manifest.
 * @param trackSelection The track selection.
 * @param dataSource A {@link DataSource} suitable for loading the media data.
 * @param trackEncryptionBoxes Track encryption boxes for the stream.
 */
public DefaultSsChunkSource(LoaderErrorThrower manifestLoaderErrorThrower, SsManifest manifest,
    int elementIndex, TrackSelection trackSelection, DataSource dataSource,
    TrackEncryptionBox[] trackEncryptionBoxes) {
  this.manifestLoaderErrorThrower = manifestLoaderErrorThrower;
  this.manifest = manifest;
  this.elementIndex = elementIndex;
  this.trackSelection = trackSelection;
  this.dataSource = dataSource;

  StreamElement streamElement = manifest.streamElements[elementIndex];

  extractorWrappers = new ChunkExtractorWrapper[trackSelection.length()];
  for (int i = 0; i < extractorWrappers.length; i++) {
    int manifestTrackIndex = trackSelection.getIndexInTrackGroup(i);
    Format format = streamElement.formats[manifestTrackIndex];
    int nalUnitLengthFieldLength = streamElement.type == C.TRACK_TYPE_VIDEO ? 4 : 0;
    Track track = new Track(manifestTrackIndex, streamElement.type, streamElement.timescale,
        C.TIME_UNSET, manifest.durationUs, format, Track.TRANSFORMATION_NONE,
        trackEncryptionBoxes, nalUnitLengthFieldLength, null, null);
    FragmentedMp4Extractor extractor = new FragmentedMp4Extractor(
        FragmentedMp4Extractor.FLAG_WORKAROUND_EVERY_VIDEO_FRAME_IS_SYNC_FRAME
        | FragmentedMp4Extractor.FLAG_WORKAROUND_IGNORE_TFDT_BOX, null, track);
    extractorWrappers[i] = new ChunkExtractorWrapper(extractor, format);
  }
}
 

private static void loadInitializationData(DataSource dataSource,
    Representation representation, ChunkExtractorWrapper extractorWrapper, RangedUri requestUri)
    throws IOException, InterruptedException {
  DataSpec dataSpec = new DataSpec(requestUri.resolveUri(representation.baseUrl),
      requestUri.start, requestUri.length, representation.getCacheKey());
  InitializationChunk initializationChunk = new InitializationChunk(dataSource, dataSpec,
      representation.format, C.SELECTION_REASON_UNKNOWN, null /* trackSelectionData */,
      extractorWrapper);
  initializationChunk.load();
}
 

private static ChunkExtractorWrapper newWrappedExtractor(int trackType, Format format) {
  String mimeType = format.containerMimeType;
  boolean isWebm =
      mimeType != null
          && (mimeType.startsWith(MimeTypes.VIDEO_WEBM)
              || mimeType.startsWith(MimeTypes.AUDIO_WEBM));
  Extractor extractor = isWebm ? new MatroskaExtractor() : new FragmentedMp4Extractor();
  return new ChunkExtractorWrapper(extractor, trackType, format);
}
 

/**
 * @param manifestLoaderErrorThrower Throws errors affecting loading of manifests.
 * @param manifest The initial manifest.
 * @param streamElementIndex The index of the stream element in the manifest.
 * @param trackSelection The track selection.
 * @param dataSource A {@link DataSource} suitable for loading the media data.
 * @param trackEncryptionBoxes Track encryption boxes for the stream.
 */
public DefaultSsChunkSource(
    LoaderErrorThrower manifestLoaderErrorThrower,
    SsManifest manifest,
    int streamElementIndex,
    TrackSelection trackSelection,
    DataSource dataSource,
    TrackEncryptionBox[] trackEncryptionBoxes) {
  this.manifestLoaderErrorThrower = manifestLoaderErrorThrower;
  this.manifest = manifest;
  this.streamElementIndex = streamElementIndex;
  this.trackSelection = trackSelection;
  this.dataSource = dataSource;

  StreamElement streamElement = manifest.streamElements[streamElementIndex];
  extractorWrappers = new ChunkExtractorWrapper[trackSelection.length()];
  for (int i = 0; i < extractorWrappers.length; i++) {
    int manifestTrackIndex = trackSelection.getIndexInTrackGroup(i);
    Format format = streamElement.formats[manifestTrackIndex];
    int nalUnitLengthFieldLength = streamElement.type == C.TRACK_TYPE_VIDEO ? 4 : 0;
    Track track = new Track(manifestTrackIndex, streamElement.type, streamElement.timescale,
        C.TIME_UNSET, manifest.durationUs, format, Track.TRANSFORMATION_NONE,
        trackEncryptionBoxes, nalUnitLengthFieldLength, null, null);
    FragmentedMp4Extractor extractor = new FragmentedMp4Extractor(
        FragmentedMp4Extractor.FLAG_WORKAROUND_EVERY_VIDEO_FRAME_IS_SYNC_FRAME
        | FragmentedMp4Extractor.FLAG_WORKAROUND_IGNORE_TFDT_BOX, null, track, null);
    extractorWrappers[i] = new ChunkExtractorWrapper(extractor, streamElement.type, format);
  }
}
 

private RepresentationHolder(
    long periodDurationUs,
    Representation representation,
    @Nullable ChunkExtractorWrapper extractorWrapper,
    long segmentNumShift,
    @Nullable DashSegmentIndex segmentIndex) {
  this.periodDurationUs = periodDurationUs;
  this.representation = representation;
  this.segmentNumShift = segmentNumShift;
  this.extractorWrapper = extractorWrapper;
  this.segmentIndex = segmentIndex;
}
 

/**
 * Loads initialization data for the {@code representation} and optionally index data then
 * returns a {@link ChunkExtractorWrapper} which contains the output.
 *
 * @param dataSource The source from which the data should be loaded.
 * @param representation The representation which initialization chunk belongs to.
 * @param loadIndex Whether to load index data too.
 * @return A {@link ChunkExtractorWrapper} for the {@code representation}, or null if no
 *     initialization or (if requested) index data exists.
 * @throws IOException Thrown when there is an error while loading.
 * @throws InterruptedException Thrown if the thread was interrupted.
 */
private static ChunkExtractorWrapper loadInitializationData(DataSource dataSource,
    Representation representation, boolean loadIndex)
    throws IOException, InterruptedException {
  RangedUri initializationUri = representation.getInitializationUri();
  if (initializationUri == null) {
    return null;
  }
  ChunkExtractorWrapper extractorWrapper = newWrappedExtractor(representation.format);
  RangedUri requestUri;
  if (loadIndex) {
    RangedUri indexUri = representation.getIndexUri();
    if (indexUri == null) {
      return null;
    }
    // It's common for initialization and index data to be stored adjacently. Attempt to merge
    // the two requests together to request both at once.
    requestUri = initializationUri.attemptMerge(indexUri, representation.baseUrl);
    if (requestUri == null) {
      loadInitializationData(dataSource, representation, extractorWrapper, initializationUri);
      requestUri = indexUri;
    }
  } else {
    requestUri = initializationUri;
  }
  loadInitializationData(dataSource, representation, extractorWrapper, requestUri);
  return extractorWrapper;
}
 

private static void loadInitializationData(DataSource dataSource,
    Representation representation, ChunkExtractorWrapper extractorWrapper, RangedUri requestUri)
    throws IOException, InterruptedException {
  DataSpec dataSpec = new DataSpec(requestUri.resolveUri(representation.baseUrl),
      requestUri.start, requestUri.length, representation.getCacheKey());
  InitializationChunk initializationChunk = new InitializationChunk(dataSource, dataSpec,
      representation.format, C.SELECTION_REASON_UNKNOWN, null /* trackSelectionData */,
      extractorWrapper);
  initializationChunk.load();
}
 

private static ChunkExtractorWrapper newWrappedExtractor(Format format) {
  String mimeType = format.containerMimeType;
  boolean isWebm = mimeType.startsWith(MimeTypes.VIDEO_WEBM)
      || mimeType.startsWith(MimeTypes.AUDIO_WEBM);
  Extractor extractor = isWebm ? new MatroskaExtractor() : new FragmentedMp4Extractor();
  return new ChunkExtractorWrapper(extractor, format);
}
 

private static MediaChunk newMediaChunk(Format format, DataSource dataSource, Uri uri,
    String cacheKey, int chunkIndex, long chunkStartTimeUs, long chunkEndTimeUs,
    int trackSelectionReason, Object trackSelectionData, ChunkExtractorWrapper extractorWrapper) {
  DataSpec dataSpec = new DataSpec(uri, 0, C.LENGTH_UNSET, cacheKey);
  // In SmoothStreaming each chunk contains sample timestamps relative to the start of the chunk.
  // To convert them the absolute timestamps, we need to set sampleOffsetUs to chunkStartTimeUs.
  long sampleOffsetUs = chunkStartTimeUs;
  return new ContainerMediaChunk(dataSource, dataSpec, format, trackSelectionReason,
      trackSelectionData, chunkStartTimeUs, chunkEndTimeUs, chunkIndex, 1, sampleOffsetUs,
      extractorWrapper);
}
 

private RepresentationHolder(
    long periodDurationUs,
    Representation representation,
    @Nullable ChunkExtractorWrapper extractorWrapper,
    long segmentNumShift,
    @Nullable DashSegmentIndex segmentIndex) {
  this.periodDurationUs = periodDurationUs;
  this.representation = representation;
  this.segmentNumShift = segmentNumShift;
  this.extractorWrapper = extractorWrapper;
  this.segmentIndex = segmentIndex;
}
 

/**
 * Loads initialization data for the {@code representation} and optionally index data then returns
 * a {@link ChunkExtractorWrapper} which contains the output.
 *
 * @param dataSource The source from which the data should be loaded.
 * @param trackType The type of the representation. Typically one of the {@link
 *     com.google.android.exoplayer2.C} {@code TRACK_TYPE_*} constants.
 * @param representation The representation which initialization chunk belongs to.
 * @param loadIndex Whether to load index data too.
 * @return A {@link ChunkExtractorWrapper} for the {@code representation}, or null if no
 *     initialization or (if requested) index data exists.
 * @throws IOException Thrown when there is an error while loading.
 * @throws InterruptedException Thrown if the thread was interrupted.
 */
private static @Nullable ChunkExtractorWrapper loadInitializationData(
    DataSource dataSource, int trackType, Representation representation, boolean loadIndex)
    throws IOException, InterruptedException {
  RangedUri initializationUri = representation.getInitializationUri();
  if (initializationUri == null) {
    return null;
  }
  ChunkExtractorWrapper extractorWrapper = newWrappedExtractor(trackType, representation.format);
  RangedUri requestUri;
  if (loadIndex) {
    RangedUri indexUri = representation.getIndexUri();
    if (indexUri == null) {
      return null;
    }
    // It's common for initialization and index data to be stored adjacently. Attempt to merge
    // the two requests together to request both at once.
    requestUri = initializationUri.attemptMerge(indexUri, representation.baseUrl);
    if (requestUri == null) {
      loadInitializationData(dataSource, representation, extractorWrapper, initializationUri);
      requestUri = indexUri;
    }
  } else {
    requestUri = initializationUri;
  }
  loadInitializationData(dataSource, representation, extractorWrapper, requestUri);
  return extractorWrapper;
}
 

private static MediaChunk newMediaChunk(
    Format format,
    DataSource dataSource,
    Uri uri,
    String cacheKey,
    int chunkIndex,
    long chunkStartTimeUs,
    long chunkEndTimeUs,
    long chunkSeekTimeUs,
    int trackSelectionReason,
    Object trackSelectionData,
    ChunkExtractorWrapper extractorWrapper) {
  DataSpec dataSpec = new DataSpec(uri, 0, C.LENGTH_UNSET, cacheKey);
  // In SmoothStreaming each chunk contains sample timestamps relative to the start of the chunk.
  // To convert them the absolute timestamps, we need to set sampleOffsetUs to chunkStartTimeUs.
  long sampleOffsetUs = chunkStartTimeUs;
  return new ContainerMediaChunk(
      dataSource,
      dataSpec,
      format,
      trackSelectionReason,
      trackSelectionData,
      chunkStartTimeUs,
      chunkEndTimeUs,
      chunkSeekTimeUs,
      chunkIndex,
      /* chunkCount= */ 1,
      sampleOffsetUs,
      extractorWrapper);
}
 

private static ChunkExtractorWrapper newWrappedExtractor(int trackType, Format format) {
  String mimeType = format.containerMimeType;
  boolean isWebm =
      mimeType != null
          && (mimeType.startsWith(MimeTypes.VIDEO_WEBM)
              || mimeType.startsWith(MimeTypes.AUDIO_WEBM));
  Extractor extractor = isWebm ? new MatroskaExtractor() : new FragmentedMp4Extractor();
  return new ChunkExtractorWrapper(extractor, trackType, format);
}
 

/**
 * @param manifestLoaderErrorThrower Throws errors affecting loading of manifests.
 * @param manifest The initial manifest.
 * @param streamElementIndex The index of the stream element in the manifest.
 * @param trackSelection The track selection.
 * @param dataSource A {@link DataSource} suitable for loading the media data.
 */
public DefaultSsChunkSource(
    LoaderErrorThrower manifestLoaderErrorThrower,
    SsManifest manifest,
    int streamElementIndex,
    TrackSelection trackSelection,
    DataSource dataSource) {
  this.manifestLoaderErrorThrower = manifestLoaderErrorThrower;
  this.manifest = manifest;
  this.streamElementIndex = streamElementIndex;
  this.trackSelection = trackSelection;
  this.dataSource = dataSource;

  StreamElement streamElement = manifest.streamElements[streamElementIndex];
  extractorWrappers = new ChunkExtractorWrapper[trackSelection.length()];
  for (int i = 0; i < extractorWrappers.length; i++) {
    int manifestTrackIndex = trackSelection.getIndexInTrackGroup(i);
    Format format = streamElement.formats[manifestTrackIndex];
    TrackEncryptionBox[] trackEncryptionBoxes =
        format.drmInitData != null ? manifest.protectionElement.trackEncryptionBoxes : null;
    int nalUnitLengthFieldLength = streamElement.type == C.TRACK_TYPE_VIDEO ? 4 : 0;
    Track track = new Track(manifestTrackIndex, streamElement.type, streamElement.timescale,
        C.TIME_UNSET, manifest.durationUs, format, Track.TRANSFORMATION_NONE,
        trackEncryptionBoxes, nalUnitLengthFieldLength, null, null);
    FragmentedMp4Extractor extractor = new FragmentedMp4Extractor(
        FragmentedMp4Extractor.FLAG_WORKAROUND_EVERY_VIDEO_FRAME_IS_SYNC_FRAME
        | FragmentedMp4Extractor.FLAG_WORKAROUND_IGNORE_TFDT_BOX, null, track, null);
    extractorWrappers[i] = new ChunkExtractorWrapper(extractor, streamElement.type, format);
  }
}
 

private static MediaChunk newMediaChunk(
    Format format,
    DataSource dataSource,
    Uri uri,
    String cacheKey,
    int chunkIndex,
    long chunkStartTimeUs,
    long chunkEndTimeUs,
    long chunkSeekTimeUs,
    int trackSelectionReason,
    Object trackSelectionData,
    ChunkExtractorWrapper extractorWrapper) {
  DataSpec dataSpec = new DataSpec(uri, 0, C.LENGTH_UNSET, cacheKey);
  // In SmoothStreaming each chunk contains sample timestamps relative to the start of the chunk.
  // To convert them the absolute timestamps, we need to set sampleOffsetUs to chunkStartTimeUs.
  long sampleOffsetUs = chunkStartTimeUs;
  return new ContainerMediaChunk(
      dataSource,
      dataSpec,
      format,
      trackSelectionReason,
      trackSelectionData,
      chunkStartTimeUs,
      chunkEndTimeUs,
      chunkSeekTimeUs,
      /* clippedEndTimeUs= */ C.TIME_UNSET,
      chunkIndex,
      /* chunkCount= */ 1,
      sampleOffsetUs,
      extractorWrapper);
}
 

private RepresentationHolder(
    long periodDurationUs,
    Representation representation,
    @Nullable ChunkExtractorWrapper extractorWrapper,
    long segmentNumShift,
    @Nullable DashSegmentIndex segmentIndex) {
  this.periodDurationUs = periodDurationUs;
  this.representation = representation;
  this.segmentNumShift = segmentNumShift;
  this.extractorWrapper = extractorWrapper;
  this.segmentIndex = segmentIndex;
}
 

/**
 * Loads initialization data for the {@code representation} and optionally index data then returns
 * a {@link ChunkExtractorWrapper} which contains the output.
 *
 * @param dataSource The source from which the data should be loaded.
 * @param trackType The type of the representation. Typically one of the {@link
 *     com.google.android.exoplayer2.C} {@code TRACK_TYPE_*} constants.
 * @param representation The representation which initialization chunk belongs to.
 * @param loadIndex Whether to load index data too.
 * @return A {@link ChunkExtractorWrapper} for the {@code representation}, or null if no
 *     initialization or (if requested) index data exists.
 * @throws IOException Thrown when there is an error while loading.
 * @throws InterruptedException Thrown if the thread was interrupted.
 */
private static @Nullable ChunkExtractorWrapper loadInitializationData(
    DataSource dataSource, int trackType, Representation representation, boolean loadIndex)
    throws IOException, InterruptedException {
  RangedUri initializationUri = representation.getInitializationUri();
  if (initializationUri == null) {
    return null;
  }
  ChunkExtractorWrapper extractorWrapper = newWrappedExtractor(trackType, representation.format);
  RangedUri requestUri;
  if (loadIndex) {
    RangedUri indexUri = representation.getIndexUri();
    if (indexUri == null) {
      return null;
    }
    // It's common for initialization and index data to be stored adjacently. Attempt to merge
    // the two requests together to request both at once.
    requestUri = initializationUri.attemptMerge(indexUri, representation.baseUrl);
    if (requestUri == null) {
      loadInitializationData(dataSource, representation, extractorWrapper, initializationUri);
      requestUri = indexUri;
    }
  } else {
    requestUri = initializationUri;
  }
  loadInitializationData(dataSource, representation, extractorWrapper, requestUri);
  return extractorWrapper;
}
 

private static void loadInitializationData(DataSource dataSource,
    Representation representation, ChunkExtractorWrapper extractorWrapper, RangedUri requestUri)
    throws IOException, InterruptedException {
  DataSpec dataSpec = new DataSpec(requestUri.resolveUri(representation.baseUrl),
      requestUri.start, requestUri.length, representation.getCacheKey());
  InitializationChunk initializationChunk = new InitializationChunk(dataSource, dataSpec,
      representation.format, C.SELECTION_REASON_UNKNOWN, null /* trackSelectionData */,
      extractorWrapper);
  initializationChunk.load();
}
 

private static ChunkExtractorWrapper newWrappedExtractor(int trackType, Format format) {
  String mimeType = format.containerMimeType;
  boolean isWebm =
      mimeType != null
          && (mimeType.startsWith(MimeTypes.VIDEO_WEBM)
              || mimeType.startsWith(MimeTypes.AUDIO_WEBM));
  Extractor extractor = isWebm ? new MatroskaExtractor() : new FragmentedMp4Extractor();
  return new ChunkExtractorWrapper(extractor, trackType, format);
}
 

/**
 * @param manifestLoaderErrorThrower Throws errors affecting loading of manifests.
 * @param manifest The initial manifest.
 * @param streamElementIndex The index of the stream element in the manifest.
 * @param trackSelection The track selection.
 * @param dataSource A {@link DataSource} suitable for loading the media data.
 */
public DefaultSsChunkSource(
    LoaderErrorThrower manifestLoaderErrorThrower,
    SsManifest manifest,
    int streamElementIndex,
    TrackSelection trackSelection,
    DataSource dataSource) {
  this.manifestLoaderErrorThrower = manifestLoaderErrorThrower;
  this.manifest = manifest;
  this.streamElementIndex = streamElementIndex;
  this.trackSelection = trackSelection;
  this.dataSource = dataSource;

  StreamElement streamElement = manifest.streamElements[streamElementIndex];
  extractorWrappers = new ChunkExtractorWrapper[trackSelection.length()];
  for (int i = 0; i < extractorWrappers.length; i++) {
    int manifestTrackIndex = trackSelection.getIndexInTrackGroup(i);
    Format format = streamElement.formats[manifestTrackIndex];
    TrackEncryptionBox[] trackEncryptionBoxes =
        format.drmInitData != null ? manifest.protectionElement.trackEncryptionBoxes : null;
    int nalUnitLengthFieldLength = streamElement.type == C.TRACK_TYPE_VIDEO ? 4 : 0;
    Track track = new Track(manifestTrackIndex, streamElement.type, streamElement.timescale,
        C.TIME_UNSET, manifest.durationUs, format, Track.TRANSFORMATION_NONE,
        trackEncryptionBoxes, nalUnitLengthFieldLength, null, null);
    FragmentedMp4Extractor extractor = new FragmentedMp4Extractor(
        FragmentedMp4Extractor.FLAG_WORKAROUND_EVERY_VIDEO_FRAME_IS_SYNC_FRAME
        | FragmentedMp4Extractor.FLAG_WORKAROUND_IGNORE_TFDT_BOX, null, track, null);
    extractorWrappers[i] = new ChunkExtractorWrapper(extractor, streamElement.type, format);
  }
}
 

private static MediaChunk newMediaChunk(
    Format format,
    DataSource dataSource,
    Uri uri,
    String cacheKey,
    int chunkIndex,
    long chunkStartTimeUs,
    long chunkEndTimeUs,
    long chunkSeekTimeUs,
    int trackSelectionReason,
    Object trackSelectionData,
    ChunkExtractorWrapper extractorWrapper) {
  DataSpec dataSpec = new DataSpec(uri, 0, C.LENGTH_UNSET, cacheKey);
  // In SmoothStreaming each chunk contains sample timestamps relative to the start of the chunk.
  // To convert them the absolute timestamps, we need to set sampleOffsetUs to chunkStartTimeUs.
  long sampleOffsetUs = chunkStartTimeUs;
  return new ContainerMediaChunk(
      dataSource,
      dataSpec,
      format,
      trackSelectionReason,
      trackSelectionData,
      chunkStartTimeUs,
      chunkEndTimeUs,
      chunkSeekTimeUs,
      /* clippedEndTimeUs= */ C.TIME_UNSET,
      chunkIndex,
      /* chunkCount= */ 1,
      sampleOffsetUs,
      extractorWrapper);
}
 

/**
 * Loads initialization data for the {@code representation} and optionally index data then returns
 * a {@link ChunkExtractorWrapper} which contains the output.
 *
 * @param dataSource The source from which the data should be loaded.
 * @param trackType The type of the representation. Typically one of the {@link
 *     com.google.android.exoplayer2.C} {@code TRACK_TYPE_*} constants.
 * @param representation The representation which initialization chunk belongs to.
 * @param loadIndex Whether to load index data too.
 * @return A {@link ChunkExtractorWrapper} for the {@code representation}, or null if no
 *     initialization or (if requested) index data exists.
 * @throws IOException Thrown when there is an error while loading.
 * @throws InterruptedException Thrown if the thread was interrupted.
 */
private static @Nullable ChunkExtractorWrapper loadInitializationData(
    DataSource dataSource, int trackType, Representation representation, boolean loadIndex)
    throws IOException, InterruptedException {
  RangedUri initializationUri = representation.getInitializationUri();
  if (initializationUri == null) {
    return null;
  }
  ChunkExtractorWrapper extractorWrapper = newWrappedExtractor(trackType, representation.format);
  RangedUri requestUri;
  if (loadIndex) {
    RangedUri indexUri = representation.getIndexUri();
    if (indexUri == null) {
      return null;
    }
    // It's common for initialization and index data to be stored adjacently. Attempt to merge
    // the two requests together to request both at once.
    requestUri = initializationUri.attemptMerge(indexUri, representation.baseUrl);
    if (requestUri == null) {
      loadInitializationData(dataSource, representation, extractorWrapper, initializationUri);
      requestUri = indexUri;
    }
  } else {
    requestUri = initializationUri;
  }
  loadInitializationData(dataSource, representation, extractorWrapper, requestUri);
  return extractorWrapper;
}
 

/**
 * Loads initialization data for the {@code representation} and optionally index data then returns
 * a {@link ChunkExtractorWrapper} which contains the output.
 *
 * @param dataSource The source from which the data should be loaded.
 * @param trackType The type of the representation. Typically one of the {@link
 *     com.google.android.exoplayer2.C} {@code TRACK_TYPE_*} constants.
 * @param representation The representation which initialization chunk belongs to.
 * @param loadIndex Whether to load index data too.
 * @return A {@link ChunkExtractorWrapper} for the {@code representation}, or null if no
 *     initialization or (if requested) index data exists.
 * @throws IOException Thrown when there is an error while loading.
 * @throws InterruptedException Thrown if the thread was interrupted.
 */
@Nullable
private static ChunkExtractorWrapper loadInitializationData(
    DataSource dataSource, int trackType, Representation representation, boolean loadIndex)
    throws IOException, InterruptedException {
  RangedUri initializationUri = representation.getInitializationUri();
  if (initializationUri == null) {
    return null;
  }
  ChunkExtractorWrapper extractorWrapper = newWrappedExtractor(trackType, representation.format);
  RangedUri requestUri;
  if (loadIndex) {
    RangedUri indexUri = representation.getIndexUri();
    if (indexUri == null) {
      return null;
    }
    // It's common for initialization and index data to be stored adjacently. Attempt to merge
    // the two requests together to request both at once.
    requestUri = initializationUri.attemptMerge(indexUri, representation.baseUrl);
    if (requestUri == null) {
      loadInitializationData(dataSource, representation, extractorWrapper, initializationUri);
      requestUri = indexUri;
    }
  } else {
    requestUri = initializationUri;
  }
  loadInitializationData(dataSource, representation, extractorWrapper, requestUri);
  return extractorWrapper;
}
 

private static void loadInitializationData(DataSource dataSource,
    Representation representation, ChunkExtractorWrapper extractorWrapper, RangedUri requestUri)
    throws IOException, InterruptedException {
  DataSpec dataSpec = new DataSpec(requestUri.resolveUri(representation.baseUrl),
      requestUri.start, requestUri.length, representation.getCacheKey());
  InitializationChunk initializationChunk = new InitializationChunk(dataSource, dataSpec,
      representation.format, C.SELECTION_REASON_UNKNOWN, null /* trackSelectionData */,
      extractorWrapper);
  initializationChunk.load();
}
 

private static ChunkExtractorWrapper newWrappedExtractor(int trackType, Format format) {
  String mimeType = format.containerMimeType;
  boolean isWebm =
      mimeType != null
          && (mimeType.startsWith(MimeTypes.VIDEO_WEBM)
              || mimeType.startsWith(MimeTypes.AUDIO_WEBM));
  Extractor extractor = isWebm ? new MatroskaExtractor() : new FragmentedMp4Extractor();
  return new ChunkExtractorWrapper(extractor, trackType, format);
}
 

/**
 * @param manifestLoaderErrorThrower Throws errors affecting loading of manifests.
 * @param manifest The initial manifest.
 * @param streamElementIndex The index of the stream element in the manifest.
 * @param trackSelection The track selection.
 * @param dataSource A {@link DataSource} suitable for loading the media data.
 */
public DefaultSsChunkSource(
    LoaderErrorThrower manifestLoaderErrorThrower,
    SsManifest manifest,
    int streamElementIndex,
    TrackSelection trackSelection,
    DataSource dataSource) {
  this.manifestLoaderErrorThrower = manifestLoaderErrorThrower;
  this.manifest = manifest;
  this.streamElementIndex = streamElementIndex;
  this.trackSelection = trackSelection;
  this.dataSource = dataSource;

  StreamElement streamElement = manifest.streamElements[streamElementIndex];
  extractorWrappers = new ChunkExtractorWrapper[trackSelection.length()];
  for (int i = 0; i < extractorWrappers.length; i++) {
    int manifestTrackIndex = trackSelection.getIndexInTrackGroup(i);
    Format format = streamElement.formats[manifestTrackIndex];
    TrackEncryptionBox[] trackEncryptionBoxes =
        format.drmInitData != null ? manifest.protectionElement.trackEncryptionBoxes : null;
    int nalUnitLengthFieldLength = streamElement.type == C.TRACK_TYPE_VIDEO ? 4 : 0;
    Track track = new Track(manifestTrackIndex, streamElement.type, streamElement.timescale,
        C.TIME_UNSET, manifest.durationUs, format, Track.TRANSFORMATION_NONE,
        trackEncryptionBoxes, nalUnitLengthFieldLength, null, null);
    FragmentedMp4Extractor extractor = new FragmentedMp4Extractor(
        FragmentedMp4Extractor.FLAG_WORKAROUND_EVERY_VIDEO_FRAME_IS_SYNC_FRAME
        | FragmentedMp4Extractor.FLAG_WORKAROUND_IGNORE_TFDT_BOX, null, track, null);
    extractorWrappers[i] = new ChunkExtractorWrapper(extractor, streamElement.type, format);
  }
}
 

private static MediaChunk newMediaChunk(
    Format format,
    DataSource dataSource,
    Uri uri,
    String cacheKey,
    int chunkIndex,
    long chunkStartTimeUs,
    long chunkEndTimeUs,
    long chunkSeekTimeUs,
    int trackSelectionReason,
    Object trackSelectionData,
    ChunkExtractorWrapper extractorWrapper) {
  DataSpec dataSpec = new DataSpec(uri, 0, C.LENGTH_UNSET, cacheKey);
  // In SmoothStreaming each chunk contains sample timestamps relative to the start of the chunk.
  // To convert them the absolute timestamps, we need to set sampleOffsetUs to chunkStartTimeUs.
  long sampleOffsetUs = chunkStartTimeUs;
  return new ContainerMediaChunk(
      dataSource,
      dataSpec,
      format,
      trackSelectionReason,
      trackSelectionData,
      chunkStartTimeUs,
      chunkEndTimeUs,
      chunkSeekTimeUs,
      /* clippedEndTimeUs= */ C.TIME_UNSET,
      chunkIndex,
      /* chunkCount= */ 1,
      sampleOffsetUs,
      extractorWrapper);
}
 

private RepresentationHolder(
    long periodDurationUs,
    Representation representation,
    @Nullable ChunkExtractorWrapper extractorWrapper,
    long segmentNumShift,
    @Nullable DashSegmentIndex segmentIndex) {
  this.periodDurationUs = periodDurationUs;
  this.representation = representation;
  this.segmentNumShift = segmentNumShift;
  this.extractorWrapper = extractorWrapper;
  this.segmentIndex = segmentIndex;
}
 

/**
 * Loads initialization data for the {@code representation} and optionally index data then returns
 * a {@link ChunkExtractorWrapper} which contains the output.
 *
 * @param dataSource The source from which the data should be loaded.
 * @param trackType The type of the representation. Typically one of the {@link
 *     com.google.android.exoplayer2.C} {@code TRACK_TYPE_*} constants.
 * @param representation The representation which initialization chunk belongs to.
 * @param loadIndex Whether to load index data too.
 * @return A {@link ChunkExtractorWrapper} for the {@code representation}, or null if no
 *     initialization or (if requested) index data exists.
 * @throws IOException Thrown when there is an error while loading.
 * @throws InterruptedException Thrown if the thread was interrupted.
 */
private static @Nullable ChunkExtractorWrapper loadInitializationData(
    DataSource dataSource, int trackType, Representation representation, boolean loadIndex)
    throws IOException, InterruptedException {
  RangedUri initializationUri = representation.getInitializationUri();
  if (initializationUri == null) {
    return null;
  }
  ChunkExtractorWrapper extractorWrapper = newWrappedExtractor(trackType, representation.format);
  RangedUri requestUri;
  if (loadIndex) {
    RangedUri indexUri = representation.getIndexUri();
    if (indexUri == null) {
      return null;
    }
    // It's common for initialization and index data to be stored adjacently. Attempt to merge
    // the two requests together to request both at once.
    requestUri = initializationUri.attemptMerge(indexUri, representation.baseUrl);
    if (requestUri == null) {
      loadInitializationData(dataSource, representation, extractorWrapper, initializationUri);
      requestUri = indexUri;
    }
  } else {
    requestUri = initializationUri;
  }
  loadInitializationData(dataSource, representation, extractorWrapper, requestUri);
  return extractorWrapper;
}
 

private static void loadInitializationData(DataSource dataSource,
    Representation representation, ChunkExtractorWrapper extractorWrapper, RangedUri requestUri)
    throws IOException, InterruptedException {
  DataSpec dataSpec = new DataSpec(requestUri.resolveUri(representation.baseUrl),
      requestUri.start, requestUri.length, representation.getCacheKey());
  InitializationChunk initializationChunk = new InitializationChunk(dataSource, dataSpec,
      representation.format, C.SELECTION_REASON_UNKNOWN, null /* trackSelectionData */,
      extractorWrapper);
  initializationChunk.load();
}