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Simplify parsing of encryption data + support SENC boxes.
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Issue: #4
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@ojw28
ojw28 committed Aug 11, 2014
1 parent 8ec8840 commit 005e98f
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Showing 3 changed files with 79 additions and 80 deletions.
1 change: 1 addition & 0 deletions library/src/main/java/com/google/android/exoplayer/parser/mp4/Atom.java
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Original file line number Diff line number Diff line change
Expand Up @@ -54,6 +54,7 @@
public static final int TYPE_frma = 0x66726D61;
public static final int TYPE_saiz = 0x7361697A;
public static final int TYPE_uuid = 0x75756964;
public static final int TYPE_senc = 0x73656E63;

public final int type;

Expand Down
135 changes: 70 additions & 65 deletions library/src/main/java/com/google/android/exoplayer/parser/mp4/FragmentedMp4Extractor.java
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Original file line number Diff line number Diff line change
Expand Up @@ -93,7 +93,7 @@ public final class FragmentedMp4Extractor {
// Parser states
private static final int STATE_READING_ATOM_HEADER = 0;
private static final int STATE_READING_ATOM_PAYLOAD = 1;
private static final int STATE_READING_CENC_AUXILIARY_DATA = 2;
private static final int STATE_READING_ENCRYPTION_DATA = 2;
private static final int STATE_READING_SAMPLE = 3;

// Atom data offsets
Expand Down Expand Up @@ -130,6 +130,7 @@ public final class FragmentedMp4Extractor {
parsedAtoms.add(Atom.TYPE_pssh);
parsedAtoms.add(Atom.TYPE_saiz);
parsedAtoms.add(Atom.TYPE_uuid);
parsedAtoms.add(Atom.TYPE_senc);
PARSED_ATOMS = Collections.unmodifiableSet(parsedAtoms);
}

Expand Down Expand Up @@ -162,8 +163,6 @@ public final class FragmentedMp4Extractor {
private int atomType;
private int atomSize;
private ParsableByteArray atomData;
private ParsableByteArray cencAuxiliaryData;
private int cencAuxiliaryBytesRead;

private int pendingSeekTimeMs;
private int sampleIndex;
Expand Down Expand Up @@ -273,8 +272,8 @@ public int read(NonBlockingInputStream inputStream, SampleHolder out)
case STATE_READING_ATOM_PAYLOAD:
results |= readAtomPayload(inputStream);
break;
case STATE_READING_CENC_AUXILIARY_DATA:
results |= readCencAuxiliaryData(inputStream);
case STATE_READING_ENCRYPTION_DATA:
results |= readEncryptionData(inputStream);
break;
default:
results |= readOrSkipSample(inputStream, out);
Expand Down Expand Up @@ -330,9 +329,6 @@ private void enterState(int state) {
rootAtomBytesRead = 0;
}
break;
case STATE_READING_CENC_AUXILIARY_DATA:
cencAuxiliaryBytesRead = 0;
break;
}
parserState = state;
}
Expand All @@ -354,12 +350,9 @@ private int readAtomHeader(NonBlockingInputStream inputStream) {
atomType = atomHeader.readInt();

if (atomType == Atom.TYPE_mdat) {
int cencAuxSize = fragmentRun.auxiliarySampleInfoTotalSize;
if (cencAuxSize > 0) {
cencAuxiliaryData = new ParsableByteArray(cencAuxSize);
enterState(STATE_READING_CENC_AUXILIARY_DATA);
if (fragmentRun.sampleEncryptionDataNeedsFill) {
enterState(STATE_READING_ENCRYPTION_DATA);
} else {
cencAuxiliaryData = null;
enterState(STATE_READING_SAMPLE);
}
return 0;
Expand Down Expand Up @@ -631,7 +624,7 @@ private static Pair<MediaFormat, TrackEncryptionBox> parseMp4aFromParent(Parsabl
if (childAtomType == Atom.TYPE_esds) {
initializationData = parseEsdsFromParent(parent, childStartPosition);
// TODO: Do we really need to do this? See [redacted]
// Update sampleRate and sampleRate from the AudioSpecificConfig initialization data.
// Update sampleRate and channelCount from the AudioSpecificConfig initialization data.
Pair<Integer, Integer> audioSpecificConfig =
CodecSpecificDataUtil.parseAudioSpecificConfig(initializationData);
sampleRate = audioSpecificConfig.first;
Expand Down Expand Up @@ -752,7 +745,7 @@ private static byte[] parseEsdsFromParent(ParsableByteArray parent, int position
parent.skip(13);

// Start of AudioSpecificConfig (defined in 14496-3)
parent.skip(1); // AudioSpecificConfig tag
parent.skip(1); // AudioSpecificConfig tag
varIntByte = parent.readUnsignedByte();
int varInt = varIntByte & 0x7F;
while (varIntByte > 127) {
Expand Down Expand Up @@ -789,26 +782,38 @@ private static int parseMfhd(ParsableByteArray mfhd) {
*/
private static void parseTraf(Track track, DefaultSampleValues extendsDefaults,
ContainerAtom traf, TrackFragment out, int workaroundFlags) {
LeafAtom saiz = traf.getLeafAtomOfType(Atom.TYPE_saiz);
if (saiz != null) {
parseSaiz(saiz.getData(), out);
}
LeafAtom tfdtAtom = traf.getLeafAtomOfType(Atom.TYPE_tfdt);
long decodeTime = tfdtAtom == null ? 0
: parseTfdt(traf.getLeafAtomOfType(Atom.TYPE_tfdt).getData());

LeafAtom tfhd = traf.getLeafAtomOfType(Atom.TYPE_tfhd);
DefaultSampleValues fragmentHeader = parseTfhd(extendsDefaults, tfhd.getData());
out.setSampleDescriptionIndex(fragmentHeader.sampleDescriptionIndex);

LeafAtom trun = traf.getLeafAtomOfType(Atom.TYPE_trun);
parseTrun(track, fragmentHeader, decodeTime, workaroundFlags, trun.getData(), out);

TrackEncryptionBox trackEncryptionBox =
track.sampleDescriptionEncryptionBoxes[fragmentHeader.sampleDescriptionIndex];
LeafAtom saiz = traf.getLeafAtomOfType(Atom.TYPE_saiz);
if (saiz != null) {
parseSaiz(trackEncryptionBox, saiz.getData(), out);
}

LeafAtom senc = traf.getLeafAtomOfType(Atom.TYPE_senc);
if (senc != null) {
parseSenc(senc.getData(), out);
}

LeafAtom uuid = traf.getLeafAtomOfType(Atom.TYPE_uuid);
if (uuid != null) {
parseUuid(uuid.getData(), out);
}
}

private static void parseSaiz(ParsableByteArray saiz, TrackFragment out) {
private static void parseSaiz(TrackEncryptionBox encryptionBox, ParsableByteArray saiz,
TrackFragment out) {
int vectorSize = encryptionBox.initializationVectorSize;
saiz.setPosition(ATOM_HEADER_SIZE);
int fullAtom = saiz.readInt();
int flags = parseFullAtomFlags(fullAtom);
Expand All @@ -818,19 +823,20 @@ private static void parseSaiz(ParsableByteArray saiz, TrackFragment out) {
int defaultSampleInfoSize = saiz.readUnsignedByte();
int sampleCount = saiz.readUnsignedIntToInt();
int totalSize = 0;
int[] sampleInfoSizes = new int[sampleCount];
boolean[] sampleHasSubsampleEncryptionTable = new boolean[sampleCount];
if (defaultSampleInfoSize == 0) {
for (int i = 0; i < sampleCount; i++) {
sampleInfoSizes[i] = saiz.readUnsignedByte();
totalSize += sampleInfoSizes[i];
int sampleInfoSize = saiz.readUnsignedByte();
totalSize += sampleInfoSize;
sampleHasSubsampleEncryptionTable[i] = sampleInfoSize > vectorSize;
}
} else {
for (int i = 0; i < sampleCount; i++) {
sampleInfoSizes[i] = defaultSampleInfoSize;
totalSize += defaultSampleInfoSize;
}
boolean subsampleEncryption = defaultSampleInfoSize > vectorSize;
totalSize += defaultSampleInfoSize * sampleCount;
Arrays.fill(sampleHasSubsampleEncryptionTable, subsampleEncryption);
}
out.setAuxiliarySampleInfoTables(totalSize, sampleInfoSizes);
out.setSampleEncryptionData(sampleHasSubsampleEncryptionTable,
new ParsableByteArray(totalSize), true);
}

/**
Expand Down Expand Up @@ -942,13 +948,8 @@ private static void parseTrun(Track track, DefaultSampleValues defaultSampleValu
}
sampleDecodingTimeTable[i] = (int) ((cumulativeTime * 1000) / timescale);
sampleSizeTable[i] = sampleSize;
boolean isSync = ((sampleFlags >> 16) & 0x1) == 0;
if (workaroundEveryVideoFrameIsSyncFrame && i != 0) {
isSync = false;
}
if (isSync) {
sampleIsSyncFrameTable[i] = true;
}
sampleIsSyncFrameTable[i] = ((sampleFlags >> 16) & 0x1) == 0
&& (!workaroundEveryVideoFrameIsSyncFrame || i == 0);
cumulativeTime += sampleDuration;
}

Expand All @@ -966,9 +967,19 @@ private static void parseUuid(ParsableByteArray uuid, TrackFragment out) {
return;
}

// See "Portable encoding of audio-video objects: The Protected Interoperable File Format
// (PIFF), John A. Bocharov et al, Section 5.3.2.1."
int fullAtom = uuid.readInt();
// Except for the extended type, this box is identical to a SENC box. See "Portable encoding of
// audio-video objects: The Protected Interoperable File Format (PIFF), John A. Bocharov et al,
// Section 5.3.2.1."
parseSenc(uuid, 16, out);
}

private static void parseSenc(ParsableByteArray senc, TrackFragment out) {
parseSenc(senc, 0, out);
}

private static void parseSenc(ParsableByteArray senc, int offset, TrackFragment out) {
senc.setPosition(ATOM_HEADER_SIZE + offset);
int fullAtom = senc.readInt();
int flags = parseFullAtomFlags(fullAtom);

if ((flags & 0x01 /* override_track_encryption_box_parameters */) != 0) {
Expand All @@ -977,15 +988,19 @@ private static void parseUuid(ParsableByteArray uuid, TrackFragment out) {
}

boolean subsampleEncryption = (flags & 0x02 /* use_subsample_encryption */) != 0;
int numberOfEntries = uuid.readUnsignedIntToInt();
if (numberOfEntries != out.length) {
throw new IllegalStateException("Length mismatch: " + numberOfEntries + ", " + out.length);
int sampleCount = senc.readUnsignedIntToInt();
if (sampleCount != out.length) {
throw new IllegalStateException("Length mismatch: " + sampleCount + ", " + out.length);
}

int sampleEncryptionDataLength = uuid.length() - uuid.getPosition();
boolean[] sampleHasSubsampleEncryptionTable = new boolean[sampleCount];
Arrays.fill(sampleHasSubsampleEncryptionTable, subsampleEncryption);

int sampleEncryptionDataLength = senc.length() - senc.getPosition();
ParsableByteArray sampleEncryptionData = new ParsableByteArray(sampleEncryptionDataLength);
uuid.readBytes(sampleEncryptionData.getData(), 0, sampleEncryptionData.length());
out.setSmoothStreamingSampleEncryptionData(sampleEncryptionData, subsampleEncryption);
senc.readBytes(sampleEncryptionData.getData(), 0, sampleEncryptionDataLength);

out.setSampleEncryptionData(sampleHasSubsampleEncryptionTable, sampleEncryptionData, false);
}

/**
Expand Down Expand Up @@ -1044,17 +1059,14 @@ private static SegmentIndex parseSidx(ParsableByteArray atom) {
return new SegmentIndex(atom.length(), sizes, offsets, durationsUs, timesUs);
}

private int readCencAuxiliaryData(NonBlockingInputStream inputStream) {
int length = cencAuxiliaryData.length();
int bytesRead = inputStream.read(cencAuxiliaryData.getData(), cencAuxiliaryBytesRead,
length - cencAuxiliaryBytesRead);
if (bytesRead == -1) {
return RESULT_END_OF_STREAM;
}
cencAuxiliaryBytesRead += bytesRead;
if (cencAuxiliaryBytesRead < length) {
private int readEncryptionData(NonBlockingInputStream inputStream) {
ParsableByteArray sampleEncryptionData = fragmentRun.sampleEncryptionData;
int sampleEncryptionDataLength = sampleEncryptionData.length();
if (inputStream.getAvailableByteCount() < sampleEncryptionDataLength) {
return RESULT_NEED_MORE_DATA;
}
inputStream.read(sampleEncryptionData.getData(), 0, sampleEncryptionDataLength);
fragmentRun.sampleEncryptionDataNeedsFill = false;
enterState(STATE_READING_SAMPLE);
return 0;
}
Expand Down Expand Up @@ -1093,15 +1105,12 @@ private int readOrSkipSample(NonBlockingInputStream inputStream, SampleHolder ou
}

private int skipSample(NonBlockingInputStream inputStream, int sampleSize) {
ParsableByteArray sampleEncryptionData = cencAuxiliaryData != null ? cencAuxiliaryData
: fragmentRun.smoothStreamingSampleEncryptionData;
ParsableByteArray sampleEncryptionData = fragmentRun.sampleEncryptionData;
if (sampleEncryptionData != null) {
TrackEncryptionBox encryptionBox =
track.sampleDescriptionEncryptionBoxes[fragmentRun.sampleDescriptionIndex];
int vectorSize = encryptionBox.initializationVectorSize;
boolean subsampleEncryption = cencAuxiliaryData != null
? fragmentRun.auxiliarySampleInfoSizeTable[sampleIndex] > vectorSize
: fragmentRun.smoothStreamingUsesSubsampleEncryption;
boolean subsampleEncryption = fragmentRun.sampleHasSubsampleEncryptionTable[sampleIndex];
sampleEncryptionData.skip(vectorSize);
int subsampleCount = subsampleEncryption ? sampleEncryptionData.readUnsignedShort() : 1;
if (subsampleEncryption) {
Expand All @@ -1128,13 +1137,11 @@ private int readSample(NonBlockingInputStream inputStream, int sampleSize, Sampl
out.flags |= MediaExtractor.SAMPLE_FLAG_SYNC;
lastSyncSampleIndex = sampleIndex;
}
if (out.allowDataBufferReplacement
&& (out.data == null || out.data.capacity() < sampleSize)) {
if (out.allowDataBufferReplacement && (out.data == null || out.data.capacity() < sampleSize)) {
outputData = ByteBuffer.allocate(sampleSize);
out.data = outputData;
}
ParsableByteArray sampleEncryptionData = cencAuxiliaryData != null ? cencAuxiliaryData
: fragmentRun.smoothStreamingSampleEncryptionData;
ParsableByteArray sampleEncryptionData = fragmentRun.sampleEncryptionData;
if (sampleEncryptionData != null) {
readSampleEncryptionData(sampleEncryptionData, out);
}
Expand Down Expand Up @@ -1173,9 +1180,7 @@ private void readSampleEncryptionData(ParsableByteArray sampleEncryptionData, Sa
byte[] keyId = encryptionBox.keyId;
boolean isEncrypted = encryptionBox.isEncrypted;
int vectorSize = encryptionBox.initializationVectorSize;
boolean subsampleEncryption = cencAuxiliaryData != null
? fragmentRun.auxiliarySampleInfoSizeTable[sampleIndex] > vectorSize
: fragmentRun.smoothStreamingUsesSubsampleEncryption;
boolean subsampleEncryption = fragmentRun.sampleHasSubsampleEncryptionTable[sampleIndex];

byte[] vector = out.cryptoInfo.iv;
if (vector == null || vector.length != 16) {
Expand Down
23 changes: 8 additions & 15 deletions library/src/main/java/com/google/android/exoplayer/parser/mp4/TrackFragment.java
View file
Original file line number Diff line number Diff line change
Expand Up @@ -27,12 +27,10 @@
public int[] sampleDecodingTimeTable;
public int[] sampleCompositionTimeOffsetTable;
public boolean[] sampleIsSyncFrameTable;
public boolean[] sampleHasSubsampleEncryptionTable;

public int auxiliarySampleInfoTotalSize;
public int[] auxiliarySampleInfoSizeTable;

public boolean smoothStreamingUsesSubsampleEncryption;
public ParsableByteArray smoothStreamingSampleEncryptionData;
public ParsableByteArray sampleEncryptionData;
public boolean sampleEncryptionDataNeedsFill;

public void setSampleDescriptionIndex(int sampleDescriptionIndex) {
this.sampleDescriptionIndex = sampleDescriptionIndex;
Expand All @@ -47,16 +45,11 @@ public void setSampleTables(int[] sampleSizeTable, int[] sampleDecodingTimeTable
this.length = sampleSizeTable.length;
}

public void setAuxiliarySampleInfoTables(int totalAuxiliarySampleInfoSize,
int[] auxiliarySampleInfoSizeTable) {
this.auxiliarySampleInfoTotalSize = totalAuxiliarySampleInfoSize;
this.auxiliarySampleInfoSizeTable = auxiliarySampleInfoSizeTable;
}

public void setSmoothStreamingSampleEncryptionData(ParsableByteArray data,
boolean usesSubsampleEncryption) {
this.smoothStreamingSampleEncryptionData = data;
this.smoothStreamingUsesSubsampleEncryption = usesSubsampleEncryption;
public void setSampleEncryptionData(boolean[] sampleHasSubsampleEncryptionTable,
ParsableByteArray sampleEncryptionData, boolean sampleEncryptionDataNeedsFill) {
this.sampleHasSubsampleEncryptionTable = sampleHasSubsampleEncryptionTable;
this.sampleEncryptionData = sampleEncryptionData;
this.sampleEncryptionDataNeedsFill = sampleEncryptionDataNeedsFill;
}

public int getSamplePresentationTime(int index) {
Expand Down

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