summaryrefslogtreecommitdiffstats
path: root/dom/media/ADTSDemuxer.cpp
diff options
context:
space:
mode:
authorMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
committerMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
commit5f8de423f190bbb79a62f804151bc24824fa32d8 (patch)
tree10027f336435511475e392454359edea8e25895d /dom/media/ADTSDemuxer.cpp
parent49ee0794b5d912db1f95dce6eb52d781dc210db5 (diff)
downloadUXP-5f8de423f190bbb79a62f804151bc24824fa32d8.tar
UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.tar.gz
UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.tar.lz
UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.tar.xz
UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.zip
Add m-esr52 at 52.6.0
Diffstat (limited to 'dom/media/ADTSDemuxer.cpp')
-rw-r--r--dom/media/ADTSDemuxer.cpp845
1 files changed, 845 insertions, 0 deletions
diff --git a/dom/media/ADTSDemuxer.cpp b/dom/media/ADTSDemuxer.cpp
new file mode 100644
index 000000000..82075b65b
--- /dev/null
+++ b/dom/media/ADTSDemuxer.cpp
@@ -0,0 +1,845 @@
+/* -*- 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 <inttypes.h>
+
+#include "nsAutoPtr.h"
+#include "VideoUtils.h"
+#include "TimeUnits.h"
+#include "prenv.h"
+
+#ifdef PR_LOGGING
+extern mozilla::LazyLogModule gMediaDemuxerLog;
+#define ADTSLOG(msg, ...) \
+ MOZ_LOG(gMediaDemuxerLog, LogLevel::Debug, ("ADTSDemuxer " msg, ##__VA_ARGS__))
+#define ADTSLOGV(msg, ...) \
+ MOZ_LOG(gMediaDemuxerLog, LogLevel::Verbose, ("ADTSDemuxer " msg, ##__VA_ARGS__))
+#else
+#define ADTSLOG(msg, ...) do {} while (false)
+#define ADTSLOGV(msg, ...) do {} while (false)
+#endif
+
+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
+ size_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 = (p[3] & 0x03) << 11 | (p[4] & 0xFF) << 3 | (p[5] & 0xE0) >> 5;
+ mNumAACFrames = (p[6] & 0x03) + 1;
+
+ static const int32_t SAMPLE_RATES[16] = {
+ 96000, 88200, 64000, 48000,
+ 44100, 32000, 24000, 22050,
+ 16000, 12000, 11025, 8000,
+ 7350
+ };
+ 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), mHeader() {}
+
+ int64_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.
+ int64_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(int64_t aOffset, uint8_t* aStart, uint8_t* aEnd) {
+ MOZ_ASSERT(aStart && aEnd);
+
+ bool found = false;
+ 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 + (ptr - aStart) - 1;
+
+ return found;
+ }
+
+private:
+ // The offset to the start of the header.
+ int64_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(int64_t aOffset, uint8_t* aStart, 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;
+};
+
+
+// Return the AAC Profile Level Indication based upon sample rate and channels
+// Information based upon table 1.10 from ISO/IEC 14496-3:2005(E)
+static int8_t
+ProfileLevelIndication(const Frame& frame)
+{
+ const FrameHeader& header = frame.Header();
+ MOZ_ASSERT(header.IsValid());
+
+ if (!header.IsValid()) {
+ return 0;
+ }
+
+ const int channels = header.mChannels;
+ const int sampleRate = header.mSampleRate;
+
+ if (channels <= 2) {
+ if (sampleRate <= 24000) {
+ // AAC Profile L1
+ return 0x28;
+ }
+ else if (sampleRate <= 48000) {
+ // AAC Profile L2
+ return 0x29;
+ }
+ }
+ else if (channels <= 5) {
+ if (sampleRate <= 48000) {
+ // AAC Profile L4
+ return 0x2A;
+ }
+ else if (sampleRate <= 96000) {
+ // AAC Profile L5
+ return 0x2B;
+ }
+ }
+
+ // TODO: Should this be 0xFE for 'no audio profile specified'?
+ return 0;
+}
+
+
+// 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
+
+// ADTSDemuxer
+
+ADTSDemuxer::ADTSDemuxer(MediaResource* aSource)
+ : mSource(aSource)
+{}
+
+bool
+ADTSDemuxer::InitInternal()
+{
+ if (!mTrackDemuxer) {
+ mTrackDemuxer = new ADTSTrackDemuxer(mSource);
+ }
+ 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__);
+}
+
+bool
+ADTSDemuxer::HasTrackType(TrackInfo::TrackType aType) const
+{
+ return aType == TrackInfo::kAudioTrack;
+}
+
+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();
+ if (length > -1)
+ return true;
+ return false;
+}
+
+
+// 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)
+{
+ Reset();
+}
+
+ADTSTrackDemuxer::~ADTSTrackDemuxer()
+{
+ delete mParser;
+ mParser = nullptr;
+}
+
+bool
+ADTSTrackDemuxer::Init()
+{
+
+ FastSeek(media::TimeUnit());
+ // 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(media::TimeUnit());
+
+ if (!mInfo) {
+ mInfo = MakeUnique<AudioInfo>();
+ }
+
+ mInfo->mRate = mSamplesPerSecond;
+ mInfo->mChannels = mChannels;
+ mInfo->mBitDepth = 16;
+ mInfo->mDuration = Duration().ToMicroseconds();
+
+ // AAC Specific information
+ mInfo->mMimeType = "audio/mp4a-latm";
+
+ // Configure AAC codec-specific values.
+
+ // According to
+ // https://msdn.microsoft.com/en-us/library/windows/desktop/dd742784%28v=vs.85%29.aspx,
+ // wAudioProfileLevelIndication, which is passed mInfo->mProfile, is
+ // a value from Table 1.12 -- audioProfileLevelIndication values, ISO/IEC 14496-3.
+ mInfo->mProfile = ProfileLevelIndication(mParser->FirstFrame());
+ // For AAC, mExtendedProfile contains the audioObjectType from Table
+ // 1.3 -- Audio Profile definition, ISO/IEC 14496-3. Eg. 2 == AAC LC
+ mInfo->mExtendedProfile = mParser->FirstFrame().Header().mObjectType;
+ InitAudioSpecificConfig(mParser->FirstFrame(), mInfo->mCodecSpecificConfig);
+
+ ADTSLOG("Init mInfo={mRate=%u mChannels=%u mBitDepth=%u mDuration=%" PRId64 "}",
+ mInfo->mRate, mInfo->mChannels, mInfo->mBitDepth, mInfo->mDuration);
+
+ return mSamplesPerSecond && mChannels;
+}
+
+UniquePtr<TrackInfo>
+ADTSTrackDemuxer::GetInfo() const
+{
+ return mInfo->Clone();
+}
+
+RefPtr<ADTSTrackDemuxer::SeekPromise>
+ADTSTrackDemuxer::Seek(media::TimeUnit aTime)
+{
+ // Efficiently seek to the position.
+ FastSeek(aTime);
+ // Correct seek position by scanning the next frames.
+ const media::TimeUnit seekTime = ScanUntil(aTime);
+
+ return SeekPromise::CreateAndResolve(seekTime, __func__);
+}
+
+media::TimeUnit
+ADTSTrackDemuxer::FastSeek(const media::TimeUnit& aTime)
+{
+ ADTSLOG("FastSeek(%" PRId64 ") avgFrameLen=%f mNumParsedFrames=%" PRIu64
+ " mFrameIndex=%" PRId64 " mOffset=%" PRIu64,
+ aTime.ToMicroseconds(), AverageFrameLength(), mNumParsedFrames,
+ mFrameIndex, mOffset);
+
+ const int64_t firstFrameOffset = mParser->FirstFrame().Offset();
+ if (!aTime.ToMicroseconds()) {
+ // Quick seek to the beginning of the stream.
+ mOffset = firstFrameOffset;
+ } else if (AverageFrameLength() > 0) {
+ mOffset = firstFrameOffset + FrameIndexFromTime(aTime) *
+ AverageFrameLength();
+ }
+
+ if (mOffset > firstFrameOffset && StreamLength() > 0) {
+ mOffset = std::min(StreamLength() - 1, mOffset);
+ }
+
+ mFrameIndex = FrameIndexFromOffset(mOffset);
+ mParser->EndFrameSession();
+
+ ADTSLOG("FastSeek End avgFrameLen=%f mNumParsedFrames=%" PRIu64
+ " mFrameIndex=%" PRId64 " mFirstFrameOffset=%llu mOffset=%" PRIu64
+ " SL=%llu",
+ AverageFrameLength(), mNumParsedFrames, mFrameIndex,
+ firstFrameOffset, mOffset, StreamLength());
+
+ return Duration(mFrameIndex);
+}
+
+media::TimeUnit
+ADTSTrackDemuxer::ScanUntil(const media::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->mSamples.AppendElement(frame);
+ }
+
+ ADTSLOGV("GetSamples() End mSamples.Size()=%d aNumSamples=%d mOffset=%" PRIu64
+ " mNumParsedFrames=%" PRIu64 " mFrameIndex=%" PRId64
+ " mTotalFrameLen=%" PRIu64 " mSamplesPerFrame=%d mSamplesPerSecond=%d "
+ "mChannels=%d",
+ frames->mSamples.Length(), aNumSamples, mOffset, mNumParsedFrames,
+ mFrameIndex, mTotalFrameLen, mSamplesPerFrame, mSamplesPerSecond,
+ mChannels);
+
+ if (frames->mSamples.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(media::TimeUnit());
+}
+
+RefPtr<ADTSTrackDemuxer::SkipAccessPointPromise>
+ADTSTrackDemuxer::SkipToNextRandomAccessPoint(media::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 mOffset;
+}
+
+media::TimeIntervals
+ADTSTrackDemuxer::GetBuffered()
+{
+ media::TimeUnit duration = Duration();
+
+ if (duration <= media::TimeUnit()) {
+ return media::TimeIntervals();
+ }
+
+ AutoPinned<MediaResource> stream(mSource.GetResource());
+ return GetEstimatedBufferedTimeRanges(stream, duration.ToMicroseconds());
+}
+
+int64_t
+ADTSTrackDemuxer::StreamLength() const
+{
+ return mSource.GetLength();
+}
+
+media::TimeUnit
+ADTSTrackDemuxer::Duration() const
+{
+ if (!mNumParsedFrames) {
+ return media::TimeUnit::FromMicroseconds(-1);
+ }
+
+ const int64_t streamLen = StreamLength();
+ if (streamLen < 0) {
+ // Unknown length, we can't estimate duration.
+ return media::TimeUnit::FromMicroseconds(-1);
+ }
+ const int64_t firstFrameOffset = mParser->FirstFrame().Offset();
+ int64_t numFrames = (streamLen - firstFrameOffset) / AverageFrameLength();
+ return Duration(numFrames);
+}
+
+media::TimeUnit
+ADTSTrackDemuxer::Duration(int64_t aNumFrames) const
+{
+ if (!mSamplesPerSecond) {
+ return media::TimeUnit::FromMicroseconds(-1);
+ }
+
+ return FramesToTimeUnit(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];
+ int32_t read = 0;
+
+ bool foundFrame = false;
+ int64_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, 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.
+ int64_t nextFrameHeaderOffset = currentFrame.Offset() + currentFrame.Length();
+ int32_t read = Read(buffer, 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.
+ int64_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()=%d ",
+ foundFrame, mParser->CurrentFrame().Length());
+ mParser->Reset();
+ return mParser->CurrentFrame();
+ }
+
+ ADTSLOGV("FindNext() End mOffset=%" PRIu64 " mNumParsedFrames=%" PRIu64
+ " mFrameIndex=%" PRId64 " frameHeaderOffset=%d"
+ " 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=%" PRId64 " HeaderSize()=%d Length()=%d})",
+ aFrame.Offset(), aFrame.Header().HeaderSize(), aFrame.PayloadLength());
+ if (!aFrame.IsValid())
+ return nullptr;
+
+ const int64_t offset = aFrame.PayloadOffset();
+ const uint32_t length = aFrame.PayloadLength();
+
+ RefPtr<MediaRawData> frame = new MediaRawData();
+ frame->mOffset = offset;
+
+ nsAutoPtr<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, length);
+ if (read != length) {
+ ADTSLOG("GetNext() Exit read=%u frame->Size()=%u", read, frame->Size());
+ return nullptr;
+ }
+
+ UpdateState(aFrame);
+
+ frame->mTime = Duration(mFrameIndex - 1).ToMicroseconds();
+ frame->mDuration = Duration(1).ToMicroseconds();
+ frame->mTimecode = frame->mTime;
+ frame->mKeyframe = true;
+
+ MOZ_ASSERT(frame->mTime >= 0);
+ MOZ_ASSERT(frame->mDuration > 0);
+
+ 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(int64_t aOffset) const
+{
+ int64_t frameIndex = 0;
+
+ if (AverageFrameLength() > 0) {
+ frameIndex = (aOffset - mParser->FirstFrame().Offset()) / AverageFrameLength();
+ }
+
+ ADTSLOGV("FrameIndexFromOffset(%" PRId64 ") -> %" PRId64, aOffset, frameIndex);
+ return std::max<int64_t>(0, frameIndex);
+}
+
+int64_t
+ADTSTrackDemuxer::FrameIndexFromTime(const media::TimeUnit& aTime) const
+{
+ int64_t frameIndex = 0;
+ if (mSamplesPerSecond > 0 && mSamplesPerFrame > 0) {
+ frameIndex = 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)
+{
+ int32_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);
+}
+
+int32_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) {
+ // Prevent blocking reads after successful initialization.
+ aSize = std::min<int64_t>(aSize, streamLen - aOffset);
+ }
+
+ 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 static_cast<int32_t>(read);
+}
+
+double
+ADTSTrackDemuxer::AverageFrameLength() const
+{
+ if (mNumParsedFrames) {
+ return static_cast<double>(mTotalFrameLen) / mNumParsedFrames;
+ }
+
+ return 0.0;
+}
+
+} // namespace mozilla