Ejemplo n.º 1
0
  /** Parses a sidx atom (defined in 14496-12). */
  private static ChunkIndex parseSidx(ParsableByteArray atom, long inputPosition)
      throws ParserException {
    atom.setPosition(Atom.HEADER_SIZE);
    int fullAtom = atom.readInt();
    int version = Atom.parseFullAtomVersion(fullAtom);

    atom.skipBytes(4);
    long timescale = atom.readUnsignedInt();
    long earliestPresentationTime;
    long offset = inputPosition;
    if (version == 0) {
      earliestPresentationTime = atom.readUnsignedInt();
      offset += atom.readUnsignedInt();
    } else {
      earliestPresentationTime = atom.readUnsignedLongToLong();
      offset += atom.readUnsignedLongToLong();
    }

    atom.skipBytes(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 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 ParserException("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.skipBytes(4);
      offset += sizes[i];
    }

    return new ChunkIndex(sizes, offsets, durationsUs, timesUs);
  }
Ejemplo n.º 2
0
  /**
   * Parses a saio atom (defined in 14496-12).
   *
   * @param saio The saio atom to parse.
   * @param out The track fragment to populate with data from the saio atom.
   */
  private static void parseSaio(ParsableByteArray saio, TrackFragment out) throws ParserException {
    saio.setPosition(Atom.HEADER_SIZE);
    int fullAtom = saio.readInt();
    int flags = Atom.parseFullAtomFlags(fullAtom);
    if ((flags & 0x01) == 1) {
      saio.skipBytes(8);
    }

    int entryCount = saio.readUnsignedIntToInt();
    if (entryCount != 1) {
      // We only support one trun element currently, so always expect one entry.
      throw new ParserException("Unexpected saio entry count: " + entryCount);
    }

    int version = Atom.parseFullAtomVersion(fullAtom);
    out.auxiliaryDataPosition +=
        version == 0 ? saio.readUnsignedInt() : saio.readUnsignedLongToLong();
  }
Ejemplo n.º 3
0
 /**
  * Parses a tfdt atom (defined in 14496-12).
  *
  * @return baseMediaDecodeTime The sum of the decode durations of all earlier samples in the
  *     media, expressed in the media's timescale.
  */
 private static long parseTfdt(ParsableByteArray tfdt) {
   tfdt.setPosition(Atom.HEADER_SIZE);
   int fullAtom = tfdt.readInt();
   int version = Atom.parseFullAtomVersion(fullAtom);
   return version == 1 ? tfdt.readUnsignedLongToLong() : tfdt.readUnsignedInt();
 }
Ejemplo n.º 4
0
  private boolean readAtomHeader(ExtractorInput input) throws IOException, InterruptedException {
    if (atomHeaderBytesRead == 0) {
      // Read the standard length atom header.
      if (!input.readFully(atomHeader.data, 0, Atom.HEADER_SIZE, true)) {
        return false;
      }
      atomHeaderBytesRead = Atom.HEADER_SIZE;
      atomHeader.setPosition(0);
      atomSize = atomHeader.readUnsignedInt();
      atomType = atomHeader.readInt();
    }

    if (atomSize == Atom.LONG_SIZE_PREFIX) {
      // Read the extended atom size.
      int headerBytesRemaining = Atom.LONG_HEADER_SIZE - Atom.HEADER_SIZE;
      input.readFully(atomHeader.data, Atom.HEADER_SIZE, headerBytesRemaining);
      atomHeaderBytesRead += headerBytesRemaining;
      atomSize = atomHeader.readUnsignedLongToLong();
    }

    long atomPosition = input.getPosition() - atomHeaderBytesRead;
    if (atomType == Atom.TYPE_moof) {
      // The data positions may be updated when parsing the tfhd/trun.
      fragmentRun.auxiliaryDataPosition = atomPosition;
      fragmentRun.dataPosition = atomPosition;
    }

    if (atomType == Atom.TYPE_mdat) {
      endOfMdatPosition = atomPosition + atomSize;
      if (!haveOutputSeekMap) {
        extractorOutput.seekMap(SeekMap.UNSEEKABLE);
        haveOutputSeekMap = true;
      }
      if (fragmentRun.sampleEncryptionDataNeedsFill) {
        parserState = STATE_READING_ENCRYPTION_DATA;
      } else {
        parserState = STATE_READING_SAMPLE_START;
      }
      return true;
    }

    if (shouldParseContainerAtom(atomType)) {
      long endPosition = input.getPosition() + atomSize - Atom.HEADER_SIZE;
      containerAtoms.add(new ContainerAtom(atomType, endPosition));
      enterReadingAtomHeaderState();
    } else if (shouldParseLeafAtom(atomType)) {
      // We don't support parsing of leaf atoms that define extended atom sizes, or that have
      // lengths greater than Integer.MAX_VALUE.
      checkState(atomHeaderBytesRead == Atom.HEADER_SIZE);
      checkState(atomSize <= Integer.MAX_VALUE);
      atomData = new ParsableByteArray((int) atomSize);
      System.arraycopy(atomHeader.data, 0, atomData.data, 0, Atom.HEADER_SIZE);
      parserState = STATE_READING_ATOM_PAYLOAD;
    } else {
      // We don't support skipping of atoms that have lengths greater than Integer.MAX_VALUE.
      checkState(atomSize <= Integer.MAX_VALUE);
      atomData = null;
      parserState = STATE_READING_ATOM_PAYLOAD;
    }

    return true;
  }