Java 类com.google.android.exoplayer.parser.SegmentIndex 实例源码

/**
 * Build a {@link SegmentIndex} containing recently gathered Cues information.
 *
 * <p>{@link #cues} is guaranteed to not be null after calling this method. In
 * the event that it can't be built, an {@link ParserException} will be thrown.
 */
private void buildCues() throws ParserException {
  if (segmentStartOffsetBytes == UNKNOWN) {
    throw new ParserException("Segment start/end offsets unknown");
  } else if (durationUs == UNKNOWN) {
    throw new ParserException("Duration unknown");
  } else if (cuesSizeBytes == UNKNOWN) {
    throw new ParserException("Cues size unknown");
  } else if (cueTimesUs == null || cueClusterPositions == null
      || cueTimesUs.size() == 0 || cueTimesUs.size() != cueClusterPositions.size()) {
    throw new ParserException("Invalid/missing cue points");
  }
  int cuePointsSize = cueTimesUs.size();
  int[] sizes = new int[cuePointsSize];
  long[] offsets = new long[cuePointsSize];
  long[] durationsUs = new long[cuePointsSize];
  long[] timesUs = new long[cuePointsSize];
  for (int i = 0; i < cuePointsSize; i++) {
    timesUs[i] = cueTimesUs.get(i);
    offsets[i] = segmentStartOffsetBytes + cueClusterPositions.get(i);
  }
  for (int i = 0; i < cuePointsSize - 1; i++) {
    sizes[i] = (int) (offsets[i + 1] - offsets[i]);
    durationsUs[i] = timesUs[i + 1] - timesUs[i];
  }
  sizes[cuePointsSize - 1] = (int) (segmentEndOffsetBytes - offsets[cuePointsSize - 1]);
  durationsUs[cuePointsSize - 1] = durationUs - timesUs[cuePointsSize - 1];
  cues = new SegmentIndex((int) cuesSizeBytes, sizes, offsets, durationsUs, timesUs);
  cueTimesUs = null;
  cueClusterPositions = null;
  readResults |= RESULT_READ_INDEX;
}

/**
 * Build a {@link SegmentIndex} containing recently gathered Cues information.
 *
 * <p>{@link #cues} is guaranteed to not be null after calling this method. In
 * the event that it can't be built, an {@link IllegalStateException} will be thrown.
 */
private void buildCues() {
  if (segmentStartOffsetBytes == UNKNOWN) {
    throw new IllegalStateException("Segment start/end offsets unknown");
  } else if (durationUs == UNKNOWN) {
    throw new IllegalStateException("Duration unknown");
  } else if (cuesSizeBytes == UNKNOWN) {
    throw new IllegalStateException("Cues size unknown");
  } else if (cueTimesUs == null || cueClusterPositions == null
      || cueTimesUs.size() == 0 || cueTimesUs.size() != cueClusterPositions.size()) {
    throw new IllegalStateException("Invalid/missing cue points");
  }
  int cuePointsSize = cueTimesUs.size();
  int[] sizes = new int[cuePointsSize];
  long[] offsets = new long[cuePointsSize];
  long[] durationsUs = new long[cuePointsSize];
  long[] timesUs = new long[cuePointsSize];
  for (int i = 0; i < cuePointsSize; i++) {
    timesUs[i] = cueTimesUs.get(i);
    offsets[i] = segmentStartOffsetBytes + cueClusterPositions.get(i);
  }
  for (int i = 0; i < cuePointsSize - 1; i++) {
    sizes[i] = (int) (offsets[i + 1] - offsets[i]);
    durationsUs[i] = timesUs[i + 1] - timesUs[i];
  }
  sizes[cuePointsSize - 1] = (int) (segmentEndOffsetBytes - offsets[cuePointsSize - 1]);
  durationsUs[cuePointsSize - 1] = durationUs - timesUs[cuePointsSize - 1];
  cues = new SegmentIndex((int) cuesSizeBytes, sizes, offsets, durationsUs, timesUs);
  cueTimesUs = null;
  cueClusterPositions = null;
  readResults |= RESULT_READ_INDEX;
}

@Override
public SegmentIndex getIndex() {
  return segmentIndex;
}

/**
 * Parses a sidx atom (defined in 14496-12).
 */
private static SegmentIndex parseSidx(ParsableByteArray atom) {
  atom.setPosition(ATOM_HEADER_SIZE);
  int fullAtom = atom.readInt();
  int version = parseFullAtomVersion(fullAtom);

  atom.skip(4);
  long timescale = atom.readUnsignedInt();
  long earliestPresentationTime;
  long firstOffset;
  if (version == 0) {
    earliestPresentationTime = atom.readUnsignedInt();
    firstOffset = atom.readUnsignedInt();
  } else {
    earliestPresentationTime = atom.readUnsignedLongToLong();
    firstOffset = atom.readUnsignedLongToLong();
  }

  atom.skip(2);

  int referenceCount = atom.readUnsignedShort();
  int[] sizes = new int[referenceCount];
  long[] offsets = new long[referenceCount];
  long[] durationsUs = new long[referenceCount];
  long[] timesUs = new long[referenceCount];

  long offset = firstOffset;
  long time = earliestPresentationTime;
  long timeUs = Util.scaleLargeTimestamp(time, C.MICROS_PER_SECOND, timescale);
  for (int i = 0; i < referenceCount; i++) {
    int firstInt = atom.readInt();

    int type = 0x80000000 & firstInt;
    if (type != 0) {
      throw new IllegalStateException("Unhandled indirect reference");
    }
    long referenceDuration = atom.readUnsignedInt();

    sizes[i] = 0x7fffffff & firstInt;
    offsets[i] = offset;

    // Calculate time and duration values such that any rounding errors are consistent. i.e. That
    // timesUs[i] + durationsUs[i] == timesUs[i + 1].
    timesUs[i] = timeUs;
    time += referenceDuration;
    timeUs = Util.scaleLargeTimestamp(time, C.MICROS_PER_SECOND, timescale);
    durationsUs[i] = timeUs - timesUs[i];

    atom.skip(4);
    offset += sizes[i];
  }

  return new SegmentIndex(atom.length(), sizes, offsets, durationsUs, timesUs);
}

@Override
public SegmentIndex getIndex() {
  return cues;
}

@Override
public SegmentIndex getIndex() {
  return segmentIndex;
}

/**
 * Parses a sidx atom (defined in 14496-12).
 */
private static SegmentIndex parseSidx(ParsableByteArray atom) {
  atom.setPosition(ATOM_HEADER_SIZE);
  int fullAtom = atom.readInt();
  int version = parseFullAtomVersion(fullAtom);

  atom.skip(4);
  long timescale = atom.readUnsignedInt();
  long earliestPresentationTime;
  long firstOffset;
  if (version == 0) {
    earliestPresentationTime = atom.readUnsignedInt();
    firstOffset = atom.readUnsignedInt();
  } else {
    earliestPresentationTime = atom.readUnsignedLongToLong();
    firstOffset = atom.readUnsignedLongToLong();
  }

  atom.skip(2);

  int referenceCount = atom.readUnsignedShort();
  int[] sizes = new int[referenceCount];
  long[] offsets = new long[referenceCount];
  long[] durationsUs = new long[referenceCount];
  long[] timesUs = new long[referenceCount];

  long offset = firstOffset;
  long time = earliestPresentationTime;
  for (int i = 0; i < referenceCount; i++) {
    int firstInt = atom.readInt();

    int type = 0x80000000 & firstInt;
    if (type != 0) {
      throw new IllegalStateException("Unhandled indirect reference");
    }
    long referenceDuration = atom.readUnsignedInt();

    sizes[i] = 0x7fffffff & firstInt;
    offsets[i] = offset;

    // Calculate time and duration values such that any rounding errors are consistent. i.e. That
    // timesUs[i] + durationsUs[i] == timesUs[i + 1].
    timesUs[i] = (time * 1000000L) / timescale;
    long nextTimeUs = ((time + referenceDuration) * 1000000L) / timescale;
    durationsUs[i] = nextTimeUs - timesUs[i];
    time += referenceDuration;

    atom.skip(4);
    offset += sizes[i];
  }

  return new SegmentIndex(atom.length(), sizes, offsets, durationsUs, timesUs);
}

@Override
public SegmentIndex getIndex() {
  return cues;
}

/**
 * @param segmentIndex The {@link SegmentIndex} to wrap.
 * @param uri The {@link Uri} where the data is located.
 * @param indexAnchor The index anchor point. This value is added to the byte offsets specified
 *     in the wrapped {@link SegmentIndex}.
 */
public DashWrappingSegmentIndex(SegmentIndex segmentIndex, Uri uri, long indexAnchor) {
  this.segmentIndex = segmentIndex;
  this.uri = uri;
  this.indexAnchor = indexAnchor;
}

/**
 * @param segmentIndex The {@link SegmentIndex} to wrap.
 * @param uri The {@link Uri} where the data is located.
 * @param indexAnchor The index anchor point. This value is added to the byte offsets specified
 *     in the wrapped {@link SegmentIndex}.
 */
public DashWrappingSegmentIndex(SegmentIndex segmentIndex, Uri uri, long indexAnchor) {
  this.segmentIndex = segmentIndex;
  this.uri = uri;
  this.indexAnchor = indexAnchor;
}