/** 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);
}
/**
* 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();
}
/**
* 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();
}
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;
}
