/** 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);
}
private int appendSampleEncryptionData(ParsableByteArray sampleEncryptionData) {
int sampleDescriptionIndex = fragmentRun.header.sampleDescriptionIndex;
TrackEncryptionBox encryptionBox =
track.sampleDescriptionEncryptionBoxes[sampleDescriptionIndex];
int vectorSize = encryptionBox.initializationVectorSize;
boolean subsampleEncryption = fragmentRun.sampleHasSubsampleEncryptionTable[sampleIndex];
// Write the signal byte, containing the vector size and the subsample encryption flag.
encryptionSignalByte.data[0] = (byte) (vectorSize | (subsampleEncryption ? 0x80 : 0));
encryptionSignalByte.setPosition(0);
trackOutput.sampleData(encryptionSignalByte, 1);
// Write the vector.
trackOutput.sampleData(sampleEncryptionData, vectorSize);
// If we don't have subsample encryption data, we're done.
if (!subsampleEncryption) {
return 1 + vectorSize;
}
// Write the subsample encryption data.
int subsampleCount = sampleEncryptionData.readUnsignedShort();
sampleEncryptionData.skipBytes(-2);
int subsampleDataLength = 2 + 6 * subsampleCount;
trackOutput.sampleData(sampleEncryptionData, subsampleDataLength);
return 1 + vectorSize + subsampleDataLength;
}
