Java NalUnitUtil类代码示例

import com.google.android.exoplayer2.util.NalUnitUtil; //导入依赖的package包/类
/**
 * @param flags Flags that control the extractor's behavior.
 * @param timestampAdjuster Adjusts sample timestamps. May be null if no adjustment is needed.
 * @param sideloadedTrack Sideloaded track information, in the case that the extractor
 *     will not receive a moov box in the input data.
 */
public FragmentedMp4Extractor(@Flags int flags, TimestampAdjuster timestampAdjuster,
    Track sideloadedTrack) {
  this.flags = flags | (sideloadedTrack != null ? FLAG_SIDELOADED : 0);
  this.timestampAdjuster = timestampAdjuster;
  this.sideloadedTrack = sideloadedTrack;
  atomHeader = new ParsableByteArray(Atom.LONG_HEADER_SIZE);
  nalStartCode = new ParsableByteArray(NalUnitUtil.NAL_START_CODE);
  nalPrefix = new ParsableByteArray(5);
  nalBuffer = new ParsableByteArray();
  encryptionSignalByte = new ParsableByteArray(1);
  extendedTypeScratch = new byte[16];
  containerAtoms = new Stack<>();
  pendingMetadataSampleInfos = new LinkedList<>();
  trackBundles = new SparseArray<>();
  durationUs = C.TIME_UNSET;
  segmentIndexEarliestPresentationTimeUs = C.TIME_UNSET;
  enterReadingAtomHeaderState();
}
 

import com.google.android.exoplayer2.util.NalUnitUtil; //导入依赖的package包/类
MatroskaExtractor(EbmlReader reader, @Flags int flags) {
  this.reader = reader;
  this.reader.init(new InnerEbmlReaderOutput());
  seekForCuesEnabled = (flags & FLAG_DISABLE_SEEK_FOR_CUES) == 0;
  varintReader = new VarintReader();
  tracks = new SparseArray<>();
  scratch = new ParsableByteArray(4);
  vorbisNumPageSamples = new ParsableByteArray(ByteBuffer.allocate(4).putInt(-1).array());
  seekEntryIdBytes = new ParsableByteArray(4);
  nalStartCode = new ParsableByteArray(NalUnitUtil.NAL_START_CODE);
  nalLength = new ParsableByteArray(4);
  sampleStrippedBytes = new ParsableByteArray();
  subripSample = new ParsableByteArray();
  encryptionInitializationVector = new ParsableByteArray(ENCRYPTION_IV_SIZE);
  encryptionSubsampleData = new ParsableByteArray();
}
 

import com.google.android.exoplayer2.util.NalUnitUtil; //导入依赖的package包/类
/**
 * @param flags Flags that control the extractor's behavior.
 * @param sideloadedTrack Sideloaded track information, in the case that the extractor
 *     will not receive a moov box in the input data.
 * @param timestampAdjuster Adjusts sample timestamps. May be null if no adjustment is needed.
 */
public FragmentedMp4Extractor(@Flags int flags, Track sideloadedTrack,
    TimestampAdjuster timestampAdjuster) {
  this.sideloadedTrack = sideloadedTrack;
  this.flags = flags | (sideloadedTrack != null ? FLAG_SIDELOADED : 0);
  this.timestampAdjuster = timestampAdjuster;
  atomHeader = new ParsableByteArray(Atom.LONG_HEADER_SIZE);
  nalStartCode = new ParsableByteArray(NalUnitUtil.NAL_START_CODE);
  nalLength = new ParsableByteArray(4);
  encryptionSignalByte = new ParsableByteArray(1);
  extendedTypeScratch = new byte[16];
  containerAtoms = new Stack<>();
  trackBundles = new SparseArray<>();
  durationUs = C.TIME_UNSET;
  enterReadingAtomHeaderState();
}
 

import com.google.android.exoplayer2.util.NalUnitUtil; //导入依赖的package包/类
/**
 * @param flags Flags that control the extractor's behavior.
 * @param timestampAdjuster Adjusts sample timestamps. May be null if no adjustment is needed.
 * @param sideloadedTrack Sideloaded track information, in the case that the extractor
 *     will not receive a moov box in the input data. Null if a moov box is expected.
 * @param sideloadedDrmInitData The {@link DrmInitData} to use for encrypted tracks. If null, the
 *     pssh boxes (if present) will be used.
 * @param closedCaptionFormats For tracks that contain SEI messages, the formats of the closed
 *     caption channels to expose.
 */
public FragmentedMp4Extractor(@Flags int flags, TimestampAdjuster timestampAdjuster,
    Track sideloadedTrack, DrmInitData sideloadedDrmInitData, List<Format> closedCaptionFormats) {
  this.flags = flags | (sideloadedTrack != null ? FLAG_SIDELOADED : 0);
  this.timestampAdjuster = timestampAdjuster;
  this.sideloadedTrack = sideloadedTrack;
  this.sideloadedDrmInitData = sideloadedDrmInitData;
  this.closedCaptionFormats = Collections.unmodifiableList(closedCaptionFormats);
  atomHeader = new ParsableByteArray(Atom.LONG_HEADER_SIZE);
  nalStartCode = new ParsableByteArray(NalUnitUtil.NAL_START_CODE);
  nalPrefix = new ParsableByteArray(5);
  nalBuffer = new ParsableByteArray();
  encryptionSignalByte = new ParsableByteArray(1);
  defaultInitializationVector = new ParsableByteArray();
  extendedTypeScratch = new byte[16];
  containerAtoms = new Stack<>();
  pendingMetadataSampleInfos = new LinkedList<>();
  trackBundles = new SparseArray<>();
  durationUs = C.TIME_UNSET;
  segmentIndexEarliestPresentationTimeUs = C.TIME_UNSET;
  enterReadingAtomHeaderState();
}
 

import com.google.android.exoplayer2.util.NalUnitUtil; //导入依赖的package包/类
MatroskaExtractor(EbmlReader reader, @Flags int flags) {
  this.reader = reader;
  this.reader.init(new InnerEbmlReaderOutput());
  seekForCuesEnabled = (flags & FLAG_DISABLE_SEEK_FOR_CUES) == 0;
  varintReader = new VarintReader();
  tracks = new SparseArray<>();
  scratch = new ParsableByteArray(4);
  vorbisNumPageSamples = new ParsableByteArray(ByteBuffer.allocate(4).putInt(-1).array());
  seekEntryIdBytes = new ParsableByteArray(4);
  nalStartCode = new ParsableByteArray(NalUnitUtil.NAL_START_CODE);
  nalLength = new ParsableByteArray(4);
  sampleStrippedBytes = new ParsableByteArray();
  subtitleSample = new ParsableByteArray();
  encryptionInitializationVector = new ParsableByteArray(ENCRYPTION_IV_SIZE);
  encryptionSubsampleData = new ParsableByteArray();
}
 

import com.google.android.exoplayer2.util.NalUnitUtil; //导入依赖的package包/类
@Override
public void seek() {
  NalUnitUtil.clearPrefixFlags(prefixFlags);
  csdBuffer.reset();
  pesPtsUsAvailable = false;
  foundFirstFrameInGroup = false;
  totalBytesWritten = 0;
}
 

import com.google.android.exoplayer2.util.NalUnitUtil; //导入依赖的package包/类
@Override
public void seek() {
  NalUnitUtil.clearPrefixFlags(prefixFlags);
  sps.reset();
  pps.reset();
  sei.reset();
  sampleReader.reset();
  totalBytesWritten = 0;
}
 

import com.google.android.exoplayer2.util.NalUnitUtil; //导入依赖的package包/类
@Override
public void seek() {
  NalUnitUtil.clearPrefixFlags(prefixFlags);
  vps.reset();
  sps.reset();
  pps.reset();
  prefixSei.reset();
  suffixSei.reset();
  sampleReader.reset();
  totalBytesWritten = 0;
}
 

import com.google.android.exoplayer2.util.NalUnitUtil; //导入依赖的package包/类
/**
 * Parses AVC configuration data.
 *
 * @param data A {@link ParsableByteArray}, whose position is set to the start of the AVC
 *     configuration data to parse.
 * @return A parsed representation of the HEVC configuration data.
 * @throws ParserException If an error occurred parsing the data.
 */
public static AvcConfig parse(ParsableByteArray data) throws ParserException {
  try {
    data.skipBytes(4); // Skip to the AVCDecoderConfigurationRecord (defined in 14496-15)
    int nalUnitLengthFieldLength = (data.readUnsignedByte() & 0x3) + 1;
    if (nalUnitLengthFieldLength == 3) {
      throw new IllegalStateException();
    }
    List<byte[]> initializationData = new ArrayList<>();
    int numSequenceParameterSets = data.readUnsignedByte() & 0x1F;
    for (int j = 0; j < numSequenceParameterSets; j++) {
      initializationData.add(buildNalUnitForChild(data));
    }
    int numPictureParameterSets = data.readUnsignedByte();
    for (int j = 0; j < numPictureParameterSets; j++) {
      initializationData.add(buildNalUnitForChild(data));
    }

    int width = Format.NO_VALUE;
    int height = Format.NO_VALUE;
    float pixelWidthAspectRatio = 1;
    if (numSequenceParameterSets > 0) {
      byte[] sps = initializationData.get(0);
      SpsData spsData = NalUnitUtil.parseSpsNalUnit(initializationData.get(0),
          nalUnitLengthFieldLength, sps.length);
      width = spsData.width;
      height = spsData.height;
      pixelWidthAspectRatio = spsData.pixelWidthAspectRatio;
    }
    return new AvcConfig(initializationData, nalUnitLengthFieldLength, width, height,
        pixelWidthAspectRatio);
  } catch (ArrayIndexOutOfBoundsException e) {
    throw new ParserException("Error parsing AVC config", e);
  }
}
 

import com.google.android.exoplayer2.util.NalUnitUtil; //导入依赖的package包/类
MatroskaExtractor(EbmlReader reader) {
  this.reader = reader;
  this.reader.init(new InnerEbmlReaderOutput());
  varintReader = new VarintReader();
  tracks = new SparseArray<>();
  scratch = new ParsableByteArray(4);
  vorbisNumPageSamples = new ParsableByteArray(ByteBuffer.allocate(4).putInt(-1).array());
  seekEntryIdBytes = new ParsableByteArray(4);
  nalStartCode = new ParsableByteArray(NalUnitUtil.NAL_START_CODE);
  nalLength = new ParsableByteArray(4);
  sampleStrippedBytes = new ParsableByteArray();
  subripSample = new ParsableByteArray();
  encryptionInitializationVector = new ParsableByteArray(ENCRYPTION_IV_SIZE);
  encryptionSubsampleData = new ParsableByteArray();
}
 

import com.google.android.exoplayer2.util.NalUnitUtil; //导入依赖的package包/类
public Mp4Extractor() {
  atomHeader = new ParsableByteArray(Atom.LONG_HEADER_SIZE);
  containerAtoms = new Stack<>();
  nalStartCode = new ParsableByteArray(NalUnitUtil.NAL_START_CODE);
  nalLength = new ParsableByteArray(4);
  enterReadingAtomHeaderState();
}
 

import com.google.android.exoplayer2.util.NalUnitUtil; //导入依赖的package包/类
@Override
public void seek() {
  NalUnitUtil.clearPrefixFlags(prefixFlags);
  csdBuffer.reset();
  totalBytesWritten = 0;
  startedFirstSample = false;
}
 

import com.google.android.exoplayer2.util.NalUnitUtil; //导入依赖的package包/类
/**
 * Creates a new extractor for unfragmented MP4 streams, using the specified flags to control the
 * extractor's behavior.
 *
 * @param flags Flags that control the extractor's behavior.
 */
public Mp4Extractor(@Flags int flags) {
  this.flags = flags;
  atomHeader = new ParsableByteArray(Atom.LONG_HEADER_SIZE);
  containerAtoms = new Stack<>();
  nalStartCode = new ParsableByteArray(NalUnitUtil.NAL_START_CODE);
  nalLength = new ParsableByteArray(4);
}
 

import com.google.android.exoplayer2.util.NalUnitUtil; //导入依赖的package包/类
@Override
public void consume(ParsableByteArray data) {
  int offset = data.getPosition();
  int limit = data.limit();
  byte[] dataArray = data.data;

  // Append the data to the buffer.
  totalBytesWritten += data.bytesLeft();
  output.sampleData(data, data.bytesLeft());

  int searchOffset = offset;
  while (true) {
    int startCodeOffset = NalUnitUtil.findNalUnit(dataArray, searchOffset, limit, prefixFlags);

    if (startCodeOffset == limit) {
      // We've scanned to the end of the data without finding another start code.
      if (!hasOutputFormat) {
        csdBuffer.onData(dataArray, offset, limit);
      }
      return;
    }

    // We've found a start code with the following value.
    int startCodeValue = data.data[startCodeOffset + 3] & 0xFF;

    if (!hasOutputFormat) {
      // This is the number of bytes from the current offset to the start of the next start
      // code. It may be negative if the start code started in the previously consumed data.
      int lengthToStartCode = startCodeOffset - offset;
      if (lengthToStartCode > 0) {
        csdBuffer.onData(dataArray, offset, startCodeOffset);
      }
      // This is the number of bytes belonging to the next start code that have already been
      // passed to csdDataTargetBuffer.
      int bytesAlreadyPassed = lengthToStartCode < 0 ? -lengthToStartCode : 0;
      if (csdBuffer.onStartCode(startCodeValue, bytesAlreadyPassed)) {
        // The csd data is complete, so we can decode and output the media format.
        Pair<Format, Long> result = parseCsdBuffer(csdBuffer, formatId);
        output.format(result.first);
        frameDurationUs = result.second;
        hasOutputFormat = true;
      }
    }

    if (hasOutputFormat && (startCodeValue == START_GROUP || startCodeValue == START_PICTURE)) {
      int bytesWrittenPastStartCode = limit - startCodeOffset;
      if (foundFirstFrameInGroup) {
        @C.BufferFlags int flags = isKeyframe ? C.BUFFER_FLAG_KEY_FRAME : 0;
        int size = (int) (totalBytesWritten - framePosition) - bytesWrittenPastStartCode;
        output.sampleMetadata(frameTimeUs, flags, size, bytesWrittenPastStartCode, null);
        isKeyframe = false;
      }
      if (startCodeValue == START_GROUP) {
        foundFirstFrameInGroup = false;
        isKeyframe = true;
      } else /* startCodeValue == START_PICTURE */ {
        frameTimeUs = pesPtsUsAvailable ? pesTimeUs : (frameTimeUs + frameDurationUs);
        framePosition = totalBytesWritten - bytesWrittenPastStartCode;
        pesPtsUsAvailable = false;
        foundFirstFrameInGroup = true;
      }
    }

    offset = startCodeOffset;
    searchOffset = offset + 3;
  }
}
 

import com.google.android.exoplayer2.util.NalUnitUtil; //导入依赖的package包/类
@Override
public void consume(ParsableByteArray data) {
  int offset = data.getPosition();
  int limit = data.limit();
  byte[] dataArray = data.data;

  // Append the data to the buffer.
  totalBytesWritten += data.bytesLeft();
  output.sampleData(data, data.bytesLeft());

  // Scan the appended data, processing NAL units as they are encountered
  while (true) {
    int nalUnitOffset = NalUnitUtil.findNalUnit(dataArray, offset, limit, prefixFlags);

    if (nalUnitOffset == limit) {
      // We've scanned to the end of the data without finding the start of another NAL unit.
      nalUnitData(dataArray, offset, limit);
      return;
    }

    // We've seen the start of a NAL unit of the following type.
    int nalUnitType = NalUnitUtil.getNalUnitType(dataArray, nalUnitOffset);

    // This is the number of bytes from the current offset to the start of the next NAL unit.
    // It may be negative if the NAL unit started in the previously consumed data.
    int lengthToNalUnit = nalUnitOffset - offset;
    if (lengthToNalUnit > 0) {
      nalUnitData(dataArray, offset, nalUnitOffset);
    }
    int bytesWrittenPastPosition = limit - nalUnitOffset;
    long absolutePosition = totalBytesWritten - bytesWrittenPastPosition;
    // Indicate the end of the previous NAL unit. If the length to the start of the next unit
    // is negative then we wrote too many bytes to the NAL buffers. Discard the excess bytes
    // when notifying that the unit has ended.
    endNalUnit(absolutePosition, bytesWrittenPastPosition,
        lengthToNalUnit < 0 ? -lengthToNalUnit : 0, pesTimeUs);
    // Indicate the start of the next NAL unit.
    startNalUnit(absolutePosition, nalUnitType, pesTimeUs);
    // Continue scanning the data.
    offset = nalUnitOffset + 3;
  }
}