Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 818 insertions, 0 deletions

diff --git a/dom/media/ADTSDemuxer.cpp b/dom/media/ADTSDemuxer.cpp
new file mode 100644
index 0000000000..29ea270461
--- /dev/null
+++ b/dom/media/ADTSDemuxer.cpp
@@ -0,0 +1,818 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "ADTSDemuxer.h"
+
+#include "TimeUnits.h"
+#include "VideoUtils.h"
+#include "mozilla/Logging.h"
+#include "mozilla/UniquePtr.h"
+#include <inttypes.h>
+
+extern mozilla::LazyLogModule gMediaDemuxerLog;
+#define LOG(msg, ...) \
+  MOZ_LOG(gMediaDemuxerLog, LogLevel::Debug, msg, ##__VA_ARGS__)
+#define ADTSLOG(msg, ...) \
+  DDMOZ_LOG(gMediaDemuxerLog, LogLevel::Debug, msg, ##__VA_ARGS__)
+#define ADTSLOGV(msg, ...) \
+  DDMOZ_LOG(gMediaDemuxerLog, LogLevel::Verbose, msg, ##__VA_ARGS__)
+
+namespace mozilla {
+namespace adts {
+
+// adts::FrameHeader - Holds the ADTS frame header and its parsing
+// state.
+//
+// ADTS Frame Structure
+//
+// 11111111 1111BCCD EEFFFFGH HHIJKLMM MMMMMMMM MMMOOOOO OOOOOOPP(QQQQQQQQ
+// QQQQQQQQ)
+//
+// Header consists of 7 or 9 bytes(without or with CRC).
+// Letter   Length(bits)  Description
+// { sync } 12            syncword 0xFFF, all bits must be 1
+// B        1             MPEG Version: 0 for MPEG-4, 1 for MPEG-2
+// C        2             Layer: always 0
+// D        1             protection absent, Warning, set to 1 if there is no
+//                        CRC and 0 if there is CRC
+// E        2             profile, the MPEG-4 Audio Object Type minus 1
+// F        4             MPEG-4 Sampling Frequency Index (15 is forbidden)
+// H        3             MPEG-4 Channel Configuration (in the case of 0, the
+//                        channel configuration is sent via an in-band PCE)
+// M        13            frame length, this value must include 7 or 9 bytes of
+//                        header length: FrameLength =
+//                          (ProtectionAbsent == 1 ? 7 : 9) + size(AACFrame)
+// O        11            Buffer fullness
+// P        2             Number of AAC frames(RDBs) in ADTS frame minus 1, for
+//                        maximum compatibility always use 1 AAC frame per ADTS
+//                        frame
+// Q        16            CRC if protection absent is 0
+class FrameHeader {
+ public:
+  uint32_t mFrameLength{};
+  uint32_t mSampleRate{};
+  uint32_t mSamples{};
+  uint32_t mChannels{};
+  uint8_t mObjectType{};
+  uint8_t mSamplingIndex{};
+  uint8_t mChannelConfig{};
+  uint8_t mNumAACFrames{};
+  bool mHaveCrc{};
+
+  // Returns whether aPtr matches a valid ADTS header sync marker
+  static bool MatchesSync(const uint8_t* aPtr) {
+    return aPtr[0] == 0xFF && (aPtr[1] & 0xF6) == 0xF0;
+  }
+
+  FrameHeader() { Reset(); }
+
+  // Header size
+  uint64_t HeaderSize() const { return (mHaveCrc) ? 9 : 7; }
+
+  bool IsValid() const { return mFrameLength > 0; }
+
+  // Resets the state to allow for a new parsing session.
+  void Reset() { PodZero(this); }
+
+  // Returns whether the byte creates a valid sequence up to this point.
+  bool Parse(const uint8_t* aPtr) {
+    const uint8_t* p = aPtr;
+
+    if (!MatchesSync(p)) {
+      return false;
+    }
+
+    // AAC has 1024 samples per frame per channel.
+    mSamples = 1024;
+
+    mHaveCrc = !(p[1] & 0x01);
+    mObjectType = ((p[2] & 0xC0) >> 6) + 1;
+    mSamplingIndex = (p[2] & 0x3C) >> 2;
+    mChannelConfig = (p[2] & 0x01) << 2 | (p[3] & 0xC0) >> 6;
+    mFrameLength = static_cast<uint32_t>(
+        (p[3] & 0x03) << 11 | (p[4] & 0xFF) << 3 | (p[5] & 0xE0) >> 5);
+    mNumAACFrames = (p[6] & 0x03) + 1;
+
+    static const uint32_t SAMPLE_RATES[] = {96000, 88200, 64000, 48000, 44100,
+                                            32000, 24000, 22050, 16000, 12000,
+                                            11025, 8000,  7350};
+    if (mSamplingIndex >= ArrayLength(SAMPLE_RATES)) {
+      LOG(("ADTS: Init() failure: invalid sample-rate index value: %" PRIu32
+           ".",
+           mSamplingIndex));
+      return false;
+    }
+    mSampleRate = SAMPLE_RATES[mSamplingIndex];
+
+    MOZ_ASSERT(mChannelConfig < 8);
+    mChannels = (mChannelConfig == 7) ? 8 : mChannelConfig;
+
+    return true;
+  }
+};
+
+// adts::Frame - Frame meta container used to parse and hold a frame
+// header and side info.
+class Frame {
+ public:
+  Frame() : mOffset(0) {}
+
+  uint64_t Offset() const { return mOffset; }
+  size_t Length() const {
+    // TODO: If fields are zero'd when invalid, this check wouldn't be
+    // necessary.
+    if (!mHeader.IsValid()) {
+      return 0;
+    }
+
+    return mHeader.mFrameLength;
+  }
+
+  // Returns the offset to the start of frame's raw data.
+  uint64_t PayloadOffset() const { return mOffset + mHeader.HeaderSize(); }
+
+  // Returns the length of the frame's raw data (excluding the header) in bytes.
+  size_t PayloadLength() const {
+    // TODO: If fields are zero'd when invalid, this check wouldn't be
+    // necessary.
+    if (!mHeader.IsValid()) {
+      return 0;
+    }
+
+    return mHeader.mFrameLength - mHeader.HeaderSize();
+  }
+
+  // Returns the parsed frame header.
+  const FrameHeader& Header() const { return mHeader; }
+
+  bool IsValid() const { return mHeader.IsValid(); }
+
+  // Resets the frame header and data.
+  void Reset() {
+    mHeader.Reset();
+    mOffset = 0;
+  }
+
+  // Returns whether the valid
+  bool Parse(uint64_t aOffset, const uint8_t* aStart, const uint8_t* aEnd) {
+    MOZ_ASSERT(aStart && aEnd);
+
+    bool found = false;
+    const uint8_t* ptr = aStart;
+    // Require at least 7 bytes of data at the end of the buffer for the minimum
+    // ADTS frame header.
+    while (ptr < aEnd - 7 && !found) {
+      found = mHeader.Parse(ptr);
+      ptr++;
+    }
+
+    mOffset = aOffset + (static_cast<size_t>(ptr - aStart)) - 1u;
+
+    return found;
+  }
+
+ private:
+  // The offset to the start of the header.
+  uint64_t mOffset;
+
+  // The currently parsed frame header.
+  FrameHeader mHeader;
+};
+
+class FrameParser {
+ public:
+  // Returns the currently parsed frame. Reset via Reset or EndFrameSession.
+  const Frame& CurrentFrame() const { return mFrame; }
+
+  // Returns the first parsed frame. Reset via Reset.
+  const Frame& FirstFrame() const { return mFirstFrame; }
+
+  // Resets the parser. Don't use between frames as first frame data is reset.
+  void Reset() {
+    EndFrameSession();
+    mFirstFrame.Reset();
+  }
+
+  // Clear the last parsed frame to allow for next frame parsing, i.e.:
+  // - sets PrevFrame to CurrentFrame
+  // - resets the CurrentFrame
+  // - resets ID3Header if no valid header was parsed yet
+  void EndFrameSession() { mFrame.Reset(); }
+
+  // Parses contents of given ByteReader for a valid frame header and returns
+  // true if one was found. After returning, the variable passed to
+  // 'aBytesToSkip' holds the amount of bytes to be skipped (if any) in order to
+  // jump across a large ID3v2 tag spanning multiple buffers.
+  bool Parse(uint64_t aOffset, const uint8_t* aStart, const uint8_t* aEnd) {
+    const bool found = mFrame.Parse(aOffset, aStart, aEnd);
+
+    if (mFrame.Length() && !mFirstFrame.Length()) {
+      mFirstFrame = mFrame;
+    }
+
+    return found;
+  }
+
+ private:
+  // We keep the first parsed frame around for static info access, the
+  // previously parsed frame for debugging and the currently parsed frame.
+  Frame mFirstFrame;
+  Frame mFrame;
+};
+
+// Initialize the AAC AudioSpecificConfig.
+// Only handles two-byte version for AAC-LC.
+static void InitAudioSpecificConfig(const Frame& frame,
+                                    MediaByteBuffer* aBuffer) {
+  const FrameHeader& header = frame.Header();
+  MOZ_ASSERT(header.IsValid());
+
+  int audioObjectType = header.mObjectType;
+  int samplingFrequencyIndex = header.mSamplingIndex;
+  int channelConfig = header.mChannelConfig;
+
+  uint8_t asc[2];
+  asc[0] = (audioObjectType & 0x1F) << 3 | (samplingFrequencyIndex & 0x0E) >> 1;
+  asc[1] = (samplingFrequencyIndex & 0x01) << 7 | (channelConfig & 0x0F) << 3;
+
+  aBuffer->AppendElements(asc, 2);
+}
+
+}  // namespace adts
+
+using media::TimeUnit;
+
+// ADTSDemuxer
+
+ADTSDemuxer::ADTSDemuxer(MediaResource* aSource) : mSource(aSource) {
+  DDLINKCHILD("source", aSource);
+}
+
+bool ADTSDemuxer::InitInternal() {
+  if (!mTrackDemuxer) {
+    mTrackDemuxer = new ADTSTrackDemuxer(mSource);
+    DDLINKCHILD("track demuxer", mTrackDemuxer.get());
+  }
+  return mTrackDemuxer->Init();
+}
+
+RefPtr<ADTSDemuxer::InitPromise> ADTSDemuxer::Init() {
+  if (!InitInternal()) {
+    ADTSLOG("Init() failure: waiting for data");
+
+    return InitPromise::CreateAndReject(NS_ERROR_DOM_MEDIA_METADATA_ERR,
+                                        __func__);
+  }
+
+  ADTSLOG("Init() successful");
+  return InitPromise::CreateAndResolve(NS_OK, __func__);
+}
+
+uint32_t ADTSDemuxer::GetNumberTracks(TrackInfo::TrackType aType) const {
+  return (aType == TrackInfo::kAudioTrack) ? 1 : 0;
+}
+
+already_AddRefed<MediaTrackDemuxer> ADTSDemuxer::GetTrackDemuxer(
+    TrackInfo::TrackType aType, uint32_t aTrackNumber) {
+  if (!mTrackDemuxer) {
+    return nullptr;
+  }
+
+  return RefPtr<ADTSTrackDemuxer>(mTrackDemuxer).forget();
+}
+
+bool ADTSDemuxer::IsSeekable() const {
+  int64_t length = mSource->GetLength();
+  return length > -1;
+}
+
+// ADTSTrackDemuxer
+ADTSTrackDemuxer::ADTSTrackDemuxer(MediaResource* aSource)
+    : mSource(aSource),
+      mParser(new adts::FrameParser()),
+      mOffset(0),
+      mNumParsedFrames(0),
+      mFrameIndex(0),
+      mTotalFrameLen(0),
+      mSamplesPerFrame(0),
+      mSamplesPerSecond(0),
+      mChannels(0) {
+  DDLINKCHILD("source", aSource);
+  Reset();
+}
+
+ADTSTrackDemuxer::~ADTSTrackDemuxer() { delete mParser; }
+
+bool ADTSTrackDemuxer::Init() {
+  FastSeek(TimeUnit::Zero());
+  // Read the first frame to fetch sample rate and other meta data.
+  RefPtr<MediaRawData> frame(GetNextFrame(FindNextFrame(true)));
+
+  ADTSLOG("Init StreamLength()=%" PRId64 " first-frame-found=%d",
+          StreamLength(), !!frame);
+
+  if (!frame) {
+    return false;
+  }
+
+  // Rewind back to the stream begin to avoid dropping the first frame.
+  FastSeek(TimeUnit::Zero());
+
+  if (!mSamplesPerSecond) {
+    return false;
+  }
+
+  if (!mInfo) {
+    mInfo = MakeUnique<AudioInfo>();
+  }
+
+  mInfo->mRate = mSamplesPerSecond;
+  mInfo->mChannels = mChannels;
+  mInfo->mBitDepth = 16;
+  mInfo->mDuration = Duration();
+
+  // AAC Specific information
+  mInfo->mMimeType = "audio/mp4a-latm";
+
+  // Configure AAC codec-specific values.
+  // For AAC, mProfile and mExtendedProfile contain the audioObjectType from
+  // Table 1.3 -- Audio Profile definition, ISO/IEC 14496-3. Eg. 2 == AAC LC
+  mInfo->mProfile = mInfo->mExtendedProfile =
+      mParser->FirstFrame().Header().mObjectType;
+  AudioCodecSpecificBinaryBlob blob;
+  InitAudioSpecificConfig(mParser->FirstFrame(), blob.mBinaryBlob);
+  mInfo->mCodecSpecificConfig = AudioCodecSpecificVariant{std::move(blob)};
+
+  ADTSLOG("Init mInfo={mRate=%u mChannels=%u mBitDepth=%u mDuration=%" PRId64
+          "}",
+          mInfo->mRate, mInfo->mChannels, mInfo->mBitDepth,
+          mInfo->mDuration.ToMicroseconds());
+
+  // AAC encoder delay can be 2112 (typical value when using Apple AAC encoder),
+  // or 1024 (typical value when encoding using fdk_aac, often via ffmpeg).
+  // See
+  // https://developer.apple.com/library/content/documentation/QuickTime/QTFF/QTFFAppenG/QTFFAppenG.html
+  // In an attempt to not trim valid audio data, and because ADTS doesn't
+  // provide a way to know this pre-roll value, this offets by 1024 frames.
+  mPreRoll = TimeUnit(1024, mSamplesPerSecond);
+  return mChannels;
+}
+
+UniquePtr<TrackInfo> ADTSTrackDemuxer::GetInfo() const {
+  return mInfo->Clone();
+}
+
+RefPtr<ADTSTrackDemuxer::SeekPromise> ADTSTrackDemuxer::Seek(
+    const TimeUnit& aTime) {
+  // Efficiently seek to the position.
+  const TimeUnit time = aTime > mPreRoll ? aTime - mPreRoll : TimeUnit::Zero();
+  FastSeek(time);
+  // Correct seek position by scanning the next frames.
+  const TimeUnit seekTime = ScanUntil(time);
+
+  return SeekPromise::CreateAndResolve(seekTime, __func__);
+}
+
+TimeUnit ADTSTrackDemuxer::FastSeek(const TimeUnit& aTime) {
+  ADTSLOG("FastSeek(%" PRId64 ") avgFrameLen=%f mNumParsedFrames=%" PRIu64
+          " mFrameIndex=%" PRId64 " mOffset=%" PRIu64,
+          aTime.ToMicroseconds(), AverageFrameLength(), mNumParsedFrames,
+          mFrameIndex, mOffset);
+
+  const uint64_t firstFrameOffset = mParser->FirstFrame().Offset();
+  if (!aTime.ToMicroseconds()) {
+    // Quick seek to the beginning of the stream.
+    mOffset = firstFrameOffset;
+  } else if (AverageFrameLength() > 0) {
+    mOffset =
+        firstFrameOffset +
+        AssertedCast<uint64_t>(AssertedCast<double>(FrameIndexFromTime(aTime)) *
+                               AverageFrameLength());
+  }
+
+  const int64_t streamLength = StreamLength();
+  if (mOffset > firstFrameOffset && streamLength > 0) {
+    mOffset = std::min(static_cast<uint64_t>(streamLength - 1), mOffset);
+  }
+
+  mFrameIndex = FrameIndexFromOffset(mOffset);
+  mParser->EndFrameSession();
+
+  ADTSLOG("FastSeek End avgFrameLen=%f mNumParsedFrames=%" PRIu64
+          " mFrameIndex=%" PRId64 " mFirstFrameOffset=%" PRIu64
+          " mOffset=%" PRIu64 " SL=%" PRIu64 "",
+          AverageFrameLength(), mNumParsedFrames, mFrameIndex, firstFrameOffset,
+          mOffset, streamLength);
+
+  return Duration(mFrameIndex);
+}
+
+TimeUnit ADTSTrackDemuxer::ScanUntil(const TimeUnit& aTime) {
+  ADTSLOG("ScanUntil(%" PRId64 ") avgFrameLen=%f mNumParsedFrames=%" PRIu64
+          " mFrameIndex=%" PRId64 " mOffset=%" PRIu64,
+          aTime.ToMicroseconds(), AverageFrameLength(), mNumParsedFrames,
+          mFrameIndex, mOffset);
+
+  if (!aTime.ToMicroseconds()) {
+    return FastSeek(aTime);
+  }
+
+  if (Duration(mFrameIndex) > aTime) {
+    FastSeek(aTime);
+  }
+
+  while (SkipNextFrame(FindNextFrame()) && Duration(mFrameIndex + 1) < aTime) {
+    ADTSLOGV("ScanUntil* avgFrameLen=%f mNumParsedFrames=%" PRIu64
+             " mFrameIndex=%" PRId64 " mOffset=%" PRIu64 " Duration=%" PRId64,
+             AverageFrameLength(), mNumParsedFrames, mFrameIndex, mOffset,
+             Duration(mFrameIndex + 1).ToMicroseconds());
+  }
+
+  ADTSLOG("ScanUntil End avgFrameLen=%f mNumParsedFrames=%" PRIu64
+          " mFrameIndex=%" PRId64 " mOffset=%" PRIu64,
+          AverageFrameLength(), mNumParsedFrames, mFrameIndex, mOffset);
+
+  return Duration(mFrameIndex);
+}
+
+RefPtr<ADTSTrackDemuxer::SamplesPromise> ADTSTrackDemuxer::GetSamples(
+    int32_t aNumSamples) {
+  ADTSLOGV("GetSamples(%d) Begin mOffset=%" PRIu64 " mNumParsedFrames=%" PRIu64
+           " mFrameIndex=%" PRId64 " mTotalFrameLen=%" PRIu64
+           " mSamplesPerFrame=%d "
+           "mSamplesPerSecond=%d mChannels=%d",
+           aNumSamples, mOffset, mNumParsedFrames, mFrameIndex, mTotalFrameLen,
+           mSamplesPerFrame, mSamplesPerSecond, mChannels);
+
+  MOZ_ASSERT(aNumSamples);
+
+  RefPtr<SamplesHolder> frames = new SamplesHolder();
+
+  while (aNumSamples--) {
+    RefPtr<MediaRawData> frame(GetNextFrame(FindNextFrame()));
+    if (!frame) break;
+    frames->AppendSample(frame);
+  }
+
+  ADTSLOGV(
+      "GetSamples() End mSamples.Size()=%zu aNumSamples=%d mOffset=%" PRIu64
+      " mNumParsedFrames=%" PRIu64 " mFrameIndex=%" PRId64
+      " mTotalFrameLen=%" PRIu64
+      " mSamplesPerFrame=%d mSamplesPerSecond=%d "
+      "mChannels=%d",
+      frames->GetSamples().Length(), aNumSamples, mOffset, mNumParsedFrames,
+      mFrameIndex, mTotalFrameLen, mSamplesPerFrame, mSamplesPerSecond,
+      mChannels);
+
+  if (frames->GetSamples().IsEmpty()) {
+    return SamplesPromise::CreateAndReject(NS_ERROR_DOM_MEDIA_END_OF_STREAM,
+                                           __func__);
+  }
+
+  return SamplesPromise::CreateAndResolve(frames, __func__);
+}
+
+void ADTSTrackDemuxer::Reset() {
+  ADTSLOG("Reset()");
+  MOZ_ASSERT(mParser);
+  if (mParser) {
+    mParser->Reset();
+  }
+  FastSeek(TimeUnit::Zero());
+}
+
+RefPtr<ADTSTrackDemuxer::SkipAccessPointPromise>
+ADTSTrackDemuxer::SkipToNextRandomAccessPoint(const TimeUnit& aTimeThreshold) {
+  // Will not be called for audio-only resources.
+  return SkipAccessPointPromise::CreateAndReject(
+      SkipFailureHolder(NS_ERROR_DOM_MEDIA_DEMUXER_ERR, 0), __func__);
+}
+
+int64_t ADTSTrackDemuxer::GetResourceOffset() const {
+  return AssertedCast<int64_t>(mOffset);
+}
+
+media::TimeIntervals ADTSTrackDemuxer::GetBuffered() {
+  auto duration = Duration();
+
+  if (duration.IsInfinite()) {
+    return media::TimeIntervals();
+  }
+
+  AutoPinned<MediaResource> stream(mSource.GetResource());
+  return GetEstimatedBufferedTimeRanges(stream, duration.ToMicroseconds());
+}
+
+int64_t ADTSTrackDemuxer::StreamLength() const { return mSource.GetLength(); }
+
+TimeUnit ADTSTrackDemuxer::Duration() const {
+  if (!mNumParsedFrames) {
+    return TimeUnit::Invalid();
+  }
+
+  const int64_t streamLen = StreamLength();
+  if (streamLen < 0) {
+    // Unknown length, we can't estimate duration, this is probably a live
+    // stream.
+    return TimeUnit::FromInfinity();
+  }
+  const int64_t firstFrameOffset =
+      AssertedCast<int64_t>(mParser->FirstFrame().Offset());
+  int64_t numFrames =
+      AssertedCast<int64_t>(AssertedCast<double>(streamLen - firstFrameOffset) /
+                            AverageFrameLength());
+  return Duration(numFrames);
+}
+
+TimeUnit ADTSTrackDemuxer::Duration(int64_t aNumFrames) const {
+  if (!mSamplesPerSecond) {
+    return TimeUnit::Invalid();
+  }
+
+  return TimeUnit(aNumFrames * mSamplesPerFrame, mSamplesPerSecond);
+}
+
+const adts::Frame& ADTSTrackDemuxer::FindNextFrame(
+    bool findFirstFrame /*= false*/) {
+  static const int BUFFER_SIZE = 4096;
+  static const int MAX_SKIPPED_BYTES = 10 * BUFFER_SIZE;
+
+  ADTSLOGV("FindNext() Begin mOffset=%" PRIu64 " mNumParsedFrames=%" PRIu64
+           " mFrameIndex=%" PRId64 " mTotalFrameLen=%" PRIu64
+           " mSamplesPerFrame=%d mSamplesPerSecond=%d mChannels=%d",
+           mOffset, mNumParsedFrames, mFrameIndex, mTotalFrameLen,
+           mSamplesPerFrame, mSamplesPerSecond, mChannels);
+
+  uint8_t buffer[BUFFER_SIZE];
+  uint32_t read = 0;
+
+  bool foundFrame = false;
+  uint64_t frameHeaderOffset = mOffset;
+
+  // Prepare the parser for the next frame parsing session.
+  mParser->EndFrameSession();
+
+  // Check whether we've found a valid ADTS frame.
+  while (!foundFrame) {
+    if ((read = Read(buffer, AssertedCast<int64_t>(frameHeaderOffset),
+                     BUFFER_SIZE)) == 0) {
+      ADTSLOG("FindNext() EOS without a frame");
+      break;
+    }
+
+    if (frameHeaderOffset - mOffset > MAX_SKIPPED_BYTES) {
+      ADTSLOG("FindNext() exceeded MAX_SKIPPED_BYTES without a frame");
+      break;
+    }
+
+    const adts::Frame& currentFrame = mParser->CurrentFrame();
+    foundFrame = mParser->Parse(frameHeaderOffset, buffer, buffer + read);
+    if (findFirstFrame && foundFrame) {
+      // Check for sync marker after the found frame, since it's
+      // possible to find sync marker in AAC data. If sync marker
+      // exists after the current frame then we've found a frame
+      // header.
+      uint64_t nextFrameHeaderOffset =
+          currentFrame.Offset() + currentFrame.Length();
+      uint32_t read =
+          Read(buffer, AssertedCast<int64_t>(nextFrameHeaderOffset), 2);
+      if (read != 2 || !adts::FrameHeader::MatchesSync(buffer)) {
+        frameHeaderOffset = currentFrame.Offset() + 1;
+        mParser->Reset();
+        foundFrame = false;
+        continue;
+      }
+    }
+
+    if (foundFrame) {
+      break;
+    }
+
+    // Minimum header size is 7 bytes.
+    uint64_t advance = read - 7;
+
+    // Check for offset overflow.
+    if (frameHeaderOffset + advance <= frameHeaderOffset) {
+      break;
+    }
+
+    frameHeaderOffset += advance;
+  }
+
+  if (!foundFrame || !mParser->CurrentFrame().Length()) {
+    ADTSLOG(
+        "FindNext() Exit foundFrame=%d mParser->CurrentFrame().Length()=%zu ",
+        foundFrame, mParser->CurrentFrame().Length());
+    mParser->Reset();
+    return mParser->CurrentFrame();
+  }
+
+  ADTSLOGV("FindNext() End mOffset=%" PRIu64 " mNumParsedFrames=%" PRIu64
+           " mFrameIndex=%" PRId64 " frameHeaderOffset=%" PRId64
+           " mTotalFrameLen=%" PRIu64
+           " mSamplesPerFrame=%d mSamplesPerSecond=%d"
+           " mChannels=%d",
+           mOffset, mNumParsedFrames, mFrameIndex, frameHeaderOffset,
+           mTotalFrameLen, mSamplesPerFrame, mSamplesPerSecond, mChannels);
+
+  return mParser->CurrentFrame();
+}
+
+bool ADTSTrackDemuxer::SkipNextFrame(const adts::Frame& aFrame) {
+  if (!mNumParsedFrames || !aFrame.Length()) {
+    RefPtr<MediaRawData> frame(GetNextFrame(aFrame));
+    return frame;
+  }
+
+  UpdateState(aFrame);
+
+  ADTSLOGV("SkipNext() End mOffset=%" PRIu64 " mNumParsedFrames=%" PRIu64
+           " mFrameIndex=%" PRId64 " mTotalFrameLen=%" PRIu64
+           " mSamplesPerFrame=%d mSamplesPerSecond=%d mChannels=%d",
+           mOffset, mNumParsedFrames, mFrameIndex, mTotalFrameLen,
+           mSamplesPerFrame, mSamplesPerSecond, mChannels);
+
+  return true;
+}
+
+already_AddRefed<MediaRawData> ADTSTrackDemuxer::GetNextFrame(
+    const adts::Frame& aFrame) {
+  ADTSLOG("GetNext() Begin({mOffset=%" PRIu64 " HeaderSize()=%" PRIu64
+          " Length()=%zu})",
+          aFrame.Offset(), aFrame.Header().HeaderSize(),
+          aFrame.PayloadLength());
+  if (!aFrame.IsValid()) return nullptr;
+
+  const int64_t offset = AssertedCast<int64_t>(aFrame.PayloadOffset());
+  const uint32_t length = aFrame.PayloadLength();
+
+  RefPtr<MediaRawData> frame = new MediaRawData();
+  frame->mOffset = offset;
+
+  UniquePtr<MediaRawDataWriter> frameWriter(frame->CreateWriter());
+  if (!frameWriter->SetSize(length)) {
+    ADTSLOG("GetNext() Exit failed to allocated media buffer");
+    return nullptr;
+  }
+
+  const uint32_t read =
+      Read(frameWriter->Data(), offset, AssertedCast<int32_t>(length));
+  if (read != length) {
+    ADTSLOG("GetNext() Exit read=%u frame->Size()=%zu", read, frame->Size());
+    return nullptr;
+  }
+
+  UpdateState(aFrame);
+
+  TimeUnit rawpts = Duration(mFrameIndex - 1) - mPreRoll;
+  TimeUnit rawDuration = Duration(1);
+  TimeUnit rawend = rawpts + rawDuration;
+
+  frame->mTime = std::max(TimeUnit::Zero(), rawpts);
+  frame->mDuration = Duration(1);
+  frame->mTimecode = frame->mTime;
+  frame->mKeyframe = true;
+
+  // Handle decoder delay. A packet must be trimmed if its pts, adjusted for
+  // decoder delay, is negative. A packet can be trimmed entirely.
+  if (rawpts.IsNegative()) {
+    frame->mDuration = std::max(TimeUnit::Zero(), rawend - frame->mTime);
+  }
+
+  // ADTS frames can have a presentation duration of zero, e.g. when a frame is
+  // part of preroll.
+  MOZ_ASSERT(frame->mDuration.IsPositiveOrZero());
+
+  ADTSLOG("ADTS packet demuxed: pts [%lf, %lf] (duration: %lf)",
+          frame->mTime.ToSeconds(), frame->GetEndTime().ToSeconds(),
+          frame->mDuration.ToSeconds());
+
+  // Indicate original packet information to trim after decoding.
+  if (frame->mDuration != rawDuration) {
+    frame->mOriginalPresentationWindow =
+        Some(media::TimeInterval{rawpts, rawend});
+    ADTSLOG("Total packet time excluding trimming: [%lf, %lf]",
+            rawpts.ToSeconds(), rawend.ToSeconds());
+  }
+
+  ADTSLOGV("GetNext() End mOffset=%" PRIu64 " mNumParsedFrames=%" PRIu64
+           " mFrameIndex=%" PRId64 " mTotalFrameLen=%" PRIu64
+           " mSamplesPerFrame=%d mSamplesPerSecond=%d mChannels=%d",
+           mOffset, mNumParsedFrames, mFrameIndex, mTotalFrameLen,
+           mSamplesPerFrame, mSamplesPerSecond, mChannels);
+
+  return frame.forget();
+}
+
+int64_t ADTSTrackDemuxer::FrameIndexFromOffset(uint64_t aOffset) const {
+  int64_t frameIndex = 0;
+
+  if (AverageFrameLength() > 0) {
+    frameIndex = AssertedCast<int64_t>(
+        AssertedCast<double>(aOffset - mParser->FirstFrame().Offset()) /
+        AverageFrameLength());
+    MOZ_ASSERT(frameIndex >= 0);
+  }
+
+  ADTSLOGV("FrameIndexFromOffset(%" PRId64 ") -> %" PRId64, aOffset,
+           frameIndex);
+  return frameIndex;
+}
+
+int64_t ADTSTrackDemuxer::FrameIndexFromTime(const TimeUnit& aTime) const {
+  int64_t frameIndex = 0;
+  if (mSamplesPerSecond > 0 && mSamplesPerFrame > 0) {
+    frameIndex = AssertedCast<int64_t>(aTime.ToSeconds() * mSamplesPerSecond /
+                                       mSamplesPerFrame) -
+                 1;
+  }
+
+  ADTSLOGV("FrameIndexFromOffset(%fs) -> %" PRId64, aTime.ToSeconds(),
+           frameIndex);
+  return std::max<int64_t>(0, frameIndex);
+}
+
+void ADTSTrackDemuxer::UpdateState(const adts::Frame& aFrame) {
+  uint32_t frameLength = aFrame.Length();
+  // Prevent overflow.
+  if (mTotalFrameLen + frameLength < mTotalFrameLen) {
+    // These variables have a linear dependency and are only used to derive the
+    // average frame length.
+    mTotalFrameLen /= 2;
+    mNumParsedFrames /= 2;
+  }
+
+  // Full frame parsed, move offset to its end.
+  mOffset = aFrame.Offset() + frameLength;
+  mTotalFrameLen += frameLength;
+
+  if (!mSamplesPerFrame) {
+    const adts::FrameHeader& header = aFrame.Header();
+    mSamplesPerFrame = header.mSamples;
+    mSamplesPerSecond = header.mSampleRate;
+    mChannels = header.mChannels;
+  }
+
+  ++mNumParsedFrames;
+  ++mFrameIndex;
+  MOZ_ASSERT(mFrameIndex > 0);
+}
+
+uint32_t ADTSTrackDemuxer::Read(uint8_t* aBuffer, int64_t aOffset,
+                                int32_t aSize) {
+  ADTSLOGV("ADTSTrackDemuxer::Read(%p %" PRId64 " %d)", aBuffer, aOffset,
+           aSize);
+
+  const int64_t streamLen = StreamLength();
+  if (mInfo && streamLen > 0) {
+    int64_t max = streamLen > aOffset ? streamLen - aOffset : 0;
+    // Prevent blocking reads after successful initialization.
+    aSize = std::min<int32_t>(aSize, AssertedCast<int32_t>(max));
+  }
+
+  uint32_t read = 0;
+  ADTSLOGV("ADTSTrackDemuxer::Read        -> ReadAt(%d)", aSize);
+  const nsresult rv = mSource.ReadAt(aOffset, reinterpret_cast<char*>(aBuffer),
+                                     static_cast<uint32_t>(aSize), &read);
+  NS_ENSURE_SUCCESS(rv, 0);
+  return read;
+}
+
+double ADTSTrackDemuxer::AverageFrameLength() const {
+  if (mNumParsedFrames) {
+    return AssertedCast<double>(mTotalFrameLen) /
+           AssertedCast<double>(mNumParsedFrames);
+  }
+
+  return 0.0;
+}
+
+/* static */
+bool ADTSDemuxer::ADTSSniffer(const uint8_t* aData, const uint32_t aLength) {
+  if (aLength < 7) {
+    return false;
+  }
+  if (!adts::FrameHeader::MatchesSync(aData)) {
+    return false;
+  }
+  auto parser = MakeUnique<adts::FrameParser>();
+
+  if (!parser->Parse(0, aData, aData + aLength)) {
+    return false;
+  }
+  const adts::Frame& currentFrame = parser->CurrentFrame();
+  // Check for sync marker after the found frame, since it's
+  // possible to find sync marker in AAC data. If sync marker
+  // exists after the current frame then we've found a frame
+  // header.
+  uint64_t nextFrameHeaderOffset =
+      currentFrame.Offset() + currentFrame.Length();
+  return aLength > nextFrameHeaderOffset &&
+         aLength - nextFrameHeaderOffset >= 2 &&
+         adts::FrameHeader::MatchesSync(aData + nextFrameHeaderOffset);
+}
+
+}  // namespace mozilla