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diff --git a/dom/media/mp3/MP3Demuxer.cpp b/dom/media/mp3/MP3Demuxer.cpp
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+++ b/dom/media/mp3/MP3Demuxer.cpp
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+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* 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 "MP3Demuxer.h"
+
+#include <algorithm>
+#include <inttypes.h>
+#include <limits>
+
+#include "ByteWriter.h"
+#include "TimeUnits.h"
+#include "VideoUtils.h"
+#include "mozilla/Assertions.h"
+
+extern mozilla::LazyLogModule gMediaDemuxerLog;
+#define MP3LOG(msg, ...) \
+ DDMOZ_LOG(gMediaDemuxerLog, LogLevel::Debug, msg, ##__VA_ARGS__)
+#define MP3LOGV(msg, ...) \
+ DDMOZ_LOG(gMediaDemuxerLog, LogLevel::Verbose, msg, ##__VA_ARGS__)
+
+using mozilla::media::TimeInterval;
+using mozilla::media::TimeIntervals;
+using mozilla::media::TimeUnit;
+
+namespace mozilla {
+
+// MP3Demuxer
+
+MP3Demuxer::MP3Demuxer(MediaResource* aSource) : mSource(aSource) {
+ DDLINKCHILD("source", aSource);
+}
+
+bool MP3Demuxer::InitInternal() {
+ if (!mTrackDemuxer) {
+ mTrackDemuxer = new MP3TrackDemuxer(mSource);
+ DDLINKCHILD("track demuxer", mTrackDemuxer.get());
+ }
+ return mTrackDemuxer->Init();
+}
+
+RefPtr<MP3Demuxer::InitPromise> MP3Demuxer::Init() {
+ if (!InitInternal()) {
+ MP3LOG("MP3Demuxer::Init() failure: waiting for data");
+
+ return InitPromise::CreateAndReject(NS_ERROR_DOM_MEDIA_METADATA_ERR,
+ __func__);
+ }
+
+ MP3LOG("MP3Demuxer::Init() successful");
+ return InitPromise::CreateAndResolve(NS_OK, __func__);
+}
+
+uint32_t MP3Demuxer::GetNumberTracks(TrackInfo::TrackType aType) const {
+ return aType == TrackInfo::kAudioTrack ? 1u : 0u;
+}
+
+already_AddRefed<MediaTrackDemuxer> MP3Demuxer::GetTrackDemuxer(
+ TrackInfo::TrackType aType, uint32_t aTrackNumber) {
+ if (!mTrackDemuxer) {
+ return nullptr;
+ }
+ return RefPtr<MP3TrackDemuxer>(mTrackDemuxer).forget();
+}
+
+bool MP3Demuxer::IsSeekable() const { return true; }
+
+void MP3Demuxer::NotifyDataArrived() {
+ // TODO: bug 1169485.
+ NS_WARNING("Unimplemented function NotifyDataArrived");
+ MP3LOGV("NotifyDataArrived()");
+}
+
+void MP3Demuxer::NotifyDataRemoved() {
+ // TODO: bug 1169485.
+ NS_WARNING("Unimplemented function NotifyDataRemoved");
+ MP3LOGV("NotifyDataRemoved()");
+}
+
+// MP3TrackDemuxer
+
+MP3TrackDemuxer::MP3TrackDemuxer(MediaResource* aSource)
+ : mSource(aSource),
+ mFrameLock(false),
+ mOffset(0),
+ mFirstFrameOffset(0),
+ mNumParsedFrames(0),
+ mFrameIndex(0),
+ mTotalFrameLen(0),
+ mSamplesPerFrame(0),
+ mSamplesPerSecond(0),
+ mChannels(0) {
+ DDLINKCHILD("source", aSource);
+ Reset();
+}
+
+bool MP3TrackDemuxer::Init() {
+ Reset();
+ FastSeek(TimeUnit());
+ // Read the first frame to fetch sample rate and other meta data.
+ RefPtr<MediaRawData> frame(GetNextFrame(FindFirstFrame()));
+
+ MP3LOG("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());
+
+ if (!mInfo) {
+ mInfo = MakeUnique<AudioInfo>();
+ }
+
+ mInfo->mRate = mSamplesPerSecond;
+ mInfo->mChannels = mChannels;
+ mInfo->mBitDepth = 16;
+ mInfo->mMimeType = "audio/mpeg";
+ mInfo->mDuration = Duration().valueOr(TimeUnit::FromInfinity());
+ Mp3CodecSpecificData mp3CodecData{};
+ if (mEncoderDelay) {
+ mp3CodecData.mEncoderDelayFrames = mEncoderDelay;
+ mp3CodecData.mEncoderPaddingFrames = mEncoderPadding;
+ }
+ mInfo->mCodecSpecificConfig =
+ AudioCodecSpecificVariant{std::move(mp3CodecData)};
+
+ MP3LOG("Init mInfo={mRate=%d mChannels=%d mBitDepth=%d mDuration=%s (%lfs)}",
+ mInfo->mRate, mInfo->mChannels, mInfo->mBitDepth,
+ mInfo->mDuration.ToString().get(), mInfo->mDuration.ToSeconds());
+
+ return mSamplesPerSecond && mChannels;
+}
+
+media::TimeUnit MP3TrackDemuxer::SeekPosition() const {
+ TimeUnit pos = Duration(mFrameIndex);
+ auto duration = Duration();
+ if (duration) {
+ pos = std::min(*duration, pos);
+ }
+ return pos;
+}
+
+const FrameParser::Frame& MP3TrackDemuxer::LastFrame() const {
+ return mParser.PrevFrame();
+}
+
+RefPtr<MediaRawData> MP3TrackDemuxer::DemuxSample() {
+ return GetNextFrame(FindNextFrame());
+}
+
+const ID3Parser::ID3Header& MP3TrackDemuxer::ID3Header() const {
+ return mParser.ID3Header();
+}
+
+const FrameParser::VBRHeader& MP3TrackDemuxer::VBRInfo() const {
+ return mParser.VBRInfo();
+}
+
+UniquePtr<TrackInfo> MP3TrackDemuxer::GetInfo() const { return mInfo->Clone(); }
+
+RefPtr<MP3TrackDemuxer::SeekPromise> MP3TrackDemuxer::Seek(
+ const TimeUnit& aTime) {
+ mRemainingEncoderPadding = AssertedCast<int32_t>(mEncoderPadding);
+ // Efficiently seek to the position.
+ FastSeek(aTime);
+ // Correct seek position by scanning the next frames.
+ const TimeUnit seekTime = ScanUntil(aTime);
+
+ return SeekPromise::CreateAndResolve(seekTime, __func__);
+}
+
+TimeUnit MP3TrackDemuxer::FastSeek(const TimeUnit& aTime) {
+ MP3LOG("FastSeek(%" PRId64 ") avgFrameLen=%f mNumParsedFrames=%" PRIu64
+ " mFrameIndex=%" PRId64 " mOffset=%" PRIu64,
+ aTime.ToMicroseconds(), AverageFrameLength(), mNumParsedFrames,
+ mFrameIndex, mOffset);
+
+ const auto& vbr = mParser.VBRInfo();
+ if (aTime.IsZero()) {
+ // Quick seek to the beginning of the stream.
+ mFrameIndex = 0;
+ } else if (vbr.IsTOCPresent() && Duration() &&
+ *Duration() != TimeUnit::Zero()) {
+ // Use TOC for more precise seeking.
+ mFrameIndex = FrameIndexFromOffset(vbr.Offset(aTime, Duration().value()));
+ } else if (AverageFrameLength() > 0) {
+ mFrameIndex = FrameIndexFromTime(aTime);
+ }
+
+ mOffset = OffsetFromFrameIndex(mFrameIndex);
+
+ if (mOffset > mFirstFrameOffset && StreamLength() > 0) {
+ mOffset = std::min(StreamLength() - 1, mOffset);
+ }
+
+ mParser.EndFrameSession();
+
+ MP3LOG("FastSeek End TOC=%d avgFrameLen=%f mNumParsedFrames=%" PRIu64
+ " mFrameIndex=%" PRId64 " mFirstFrameOffset=%" PRId64
+ " mOffset=%" PRIu64 " SL=%" PRId64 " NumBytes=%u",
+ vbr.IsTOCPresent(), AverageFrameLength(), mNumParsedFrames,
+ mFrameIndex, mFirstFrameOffset, mOffset, StreamLength(),
+ vbr.NumBytes().valueOr(0));
+
+ return Duration(mFrameIndex);
+}
+
+TimeUnit MP3TrackDemuxer::ScanUntil(const TimeUnit& aTime) {
+ MP3LOG("ScanUntil(%" PRId64 ") avgFrameLen=%f mNumParsedFrames=%" PRIu64
+ " mFrameIndex=%" PRId64 " mOffset=%" PRIu64,
+ aTime.ToMicroseconds(), AverageFrameLength(), mNumParsedFrames,
+ mFrameIndex, mOffset);
+
+ if (aTime.IsZero()) {
+ return FastSeek(aTime);
+ }
+
+ if (Duration(mFrameIndex) > aTime) {
+ // We've seeked past the target time, rewind back a little to correct it.
+ const int64_t rewind = aTime.ToMicroseconds() / 100;
+ FastSeek(aTime - TimeUnit::FromMicroseconds(rewind));
+ }
+
+ if (Duration(mFrameIndex + 1) > aTime) {
+ return SeekPosition();
+ }
+
+ MediaByteRange nextRange = FindNextFrame();
+ while (SkipNextFrame(nextRange) && Duration(mFrameIndex + 1) < aTime) {
+ nextRange = FindNextFrame();
+ MP3LOGV("ScanUntil* avgFrameLen=%f mNumParsedFrames=%" PRIu64
+ " mFrameIndex=%" PRId64 " mOffset=%" PRIu64 " Duration=%" PRId64,
+ AverageFrameLength(), mNumParsedFrames, mFrameIndex, mOffset,
+ Duration(mFrameIndex + 1).ToMicroseconds());
+ }
+
+ MP3LOG("ScanUntil End avgFrameLen=%f mNumParsedFrames=%" PRIu64
+ " mFrameIndex=%" PRId64 " mOffset=%" PRIu64,
+ AverageFrameLength(), mNumParsedFrames, mFrameIndex, mOffset);
+
+ return SeekPosition();
+}
+
+RefPtr<MP3TrackDemuxer::SamplesPromise> MP3TrackDemuxer::GetSamples(
+ int32_t aNumSamples) {
+ MP3LOGV("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);
+
+ if (!aNumSamples) {
+ return SamplesPromise::CreateAndReject(NS_ERROR_DOM_MEDIA_DEMUXER_ERR,
+ __func__);
+ }
+
+ RefPtr<SamplesHolder> frames = new SamplesHolder();
+
+ while (aNumSamples--) {
+ RefPtr<MediaRawData> frame(GetNextFrame(FindNextFrame()));
+ if (!frame) {
+ break;
+ }
+ if (!frame->HasValidTime()) {
+ return SamplesPromise::CreateAndReject(NS_ERROR_DOM_MEDIA_DEMUXER_ERR,
+ __func__);
+ }
+ frames->AppendSample(frame);
+ }
+
+ MP3LOGV("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 MP3TrackDemuxer::Reset() {
+ MP3LOG("Reset()");
+
+ FastSeek(TimeUnit());
+ mParser.Reset();
+}
+
+RefPtr<MP3TrackDemuxer::SkipAccessPointPromise>
+MP3TrackDemuxer::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 MP3TrackDemuxer::GetResourceOffset() const { return mOffset; }
+
+TimeIntervals MP3TrackDemuxer::GetBuffered() {
+ AutoPinned<MediaResource> stream(mSource.GetResource());
+ TimeIntervals buffered;
+
+ if (Duration() && stream->IsDataCachedToEndOfResource(0)) {
+ // Special case completely cached files. This also handles local files.
+ buffered += TimeInterval(TimeUnit(), *Duration());
+ MP3LOGV("buffered = [[%" PRId64 ", %" PRId64 "]]",
+ TimeUnit().ToMicroseconds(), Duration()->ToMicroseconds());
+ return buffered;
+ }
+
+ MediaByteRangeSet ranges;
+ nsresult rv = stream->GetCachedRanges(ranges);
+ NS_ENSURE_SUCCESS(rv, buffered);
+
+ for (const auto& range : ranges) {
+ if (range.IsEmpty()) {
+ continue;
+ }
+ TimeUnit start = Duration(FrameIndexFromOffset(range.mStart));
+ TimeUnit end = Duration(FrameIndexFromOffset(range.mEnd));
+ MP3LOGV("buffered += [%" PRId64 ", %" PRId64 "]", start.ToMicroseconds(),
+ end.ToMicroseconds());
+ buffered += TimeInterval(start, end);
+ }
+
+ // If the number of frames reported by the header is valid,
+ // the duration calculated from it is the maximal duration.
+ if (ValidNumAudioFrames() && Duration()) {
+ TimeInterval duration = TimeInterval(TimeUnit(), *Duration());
+ return buffered.Intersection(duration);
+ }
+
+ return buffered;
+}
+
+int64_t MP3TrackDemuxer::StreamLength() const { return mSource.GetLength(); }
+
+media::NullableTimeUnit NothingIfNegative(TimeUnit aDuration) {
+ if (aDuration.IsNegative()) {
+ return Nothing();
+ }
+ return Some(aDuration);
+}
+
+media::NullableTimeUnit MP3TrackDemuxer::Duration() const {
+ if (!mNumParsedFrames) {
+ return Nothing();
+ }
+
+ int64_t numFrames = 0;
+ const auto numAudioFrames = ValidNumAudioFrames();
+ if (numAudioFrames) {
+ // VBR headers don't include the VBR header frame.
+ numFrames = numAudioFrames.value() + 1;
+ return NothingIfNegative(Duration(numFrames) -
+ (EncoderDelay() + Padding()));
+ }
+
+ const int64_t streamLen = StreamLength();
+ if (streamLen < 0) { // Live streams.
+ // Unknown length, we can't estimate duration.
+ return Nothing();
+ }
+ // We can't early return when streamLen < 0 before checking numAudioFrames
+ // since some live radio will give an opening remark before playing music
+ // and the duration of the opening talk can be calculated by numAudioFrames.
+
+ int64_t size = streamLen - mFirstFrameOffset;
+ MOZ_ASSERT(size);
+
+ if (mParser.ID3v1MetadataFound() && size > 128) {
+ size -= 128;
+ }
+
+ // If it's CBR, calculate the duration by bitrate.
+ if (!mParser.VBRInfo().IsValid()) {
+ const uint32_t bitrate = mParser.CurrentFrame().Header().Bitrate();
+ return NothingIfNegative(
+ media::TimeUnit::FromSeconds(static_cast<double>(size) * 8 / bitrate));
+ }
+
+ if (AverageFrameLength() > 0) {
+ numFrames = std::lround(AssertedCast<double>(size) / AverageFrameLength());
+ }
+
+ return NothingIfNegative(Duration(numFrames) - (EncoderDelay() + Padding()));
+}
+
+TimeUnit MP3TrackDemuxer::Duration(int64_t aNumFrames) const {
+ if (!mSamplesPerSecond) {
+ return TimeUnit::Invalid();
+ }
+
+ const int64_t frameCount = aNumFrames * mSamplesPerFrame;
+ return TimeUnit(frameCount, mSamplesPerSecond);
+}
+
+MediaByteRange MP3TrackDemuxer::FindFirstFrame() {
+ // We attempt to find multiple successive frames to avoid locking onto a false
+ // positive if we're fed a stream that has been cut mid-frame.
+ // For compatibility reasons we have to use the same frame count as Chrome,
+ // since some web sites actually use a file that short to test our playback
+ // capabilities.
+ static const int MIN_SUCCESSIVE_FRAMES = 3;
+ mFrameLock = false;
+
+ MediaByteRange candidateFrame = FindNextFrame();
+ int numSuccFrames = candidateFrame.Length() > 0;
+ MediaByteRange currentFrame = candidateFrame;
+ MP3LOGV("FindFirst() first candidate frame: mOffset=%" PRIu64
+ " Length()=%" PRIu64,
+ candidateFrame.mStart, candidateFrame.Length());
+
+ while (candidateFrame.Length()) {
+ mParser.EndFrameSession();
+ mOffset = currentFrame.mEnd;
+ const MediaByteRange prevFrame = currentFrame;
+
+ // FindNextFrame() here will only return frames consistent with our
+ // candidate frame.
+ currentFrame = FindNextFrame();
+ numSuccFrames += currentFrame.Length() > 0;
+ // Multiple successive false positives, which wouldn't be caught by the
+ // consistency checks alone, can be detected by wrong alignment (non-zero
+ // gap between frames).
+ const int64_t frameSeparation = currentFrame.mStart - prevFrame.mEnd;
+
+ if (!currentFrame.Length() || frameSeparation != 0) {
+ MP3LOGV(
+ "FindFirst() not enough successive frames detected, "
+ "rejecting candidate frame: successiveFrames=%d, last "
+ "Length()=%" PRIu64 ", last frameSeparation=%" PRId64,
+ numSuccFrames, currentFrame.Length(), frameSeparation);
+
+ mParser.ResetFrameData();
+ mOffset = candidateFrame.mStart + 1;
+ candidateFrame = FindNextFrame();
+ numSuccFrames = candidateFrame.Length() > 0;
+ currentFrame = candidateFrame;
+ MP3LOGV("FindFirst() new candidate frame: mOffset=%" PRIu64
+ " Length()=%" PRIu64,
+ candidateFrame.mStart, candidateFrame.Length());
+ } else if (numSuccFrames >= MIN_SUCCESSIVE_FRAMES) {
+ MP3LOG(
+ "FindFirst() accepting candidate frame: "
+ "successiveFrames=%d",
+ numSuccFrames);
+ mFrameLock = true;
+ return candidateFrame;
+ } else if (prevFrame.mStart == mParser.TotalID3HeaderSize() &&
+ currentFrame.mEnd == StreamLength()) {
+ // We accept streams with only two frames if both frames are valid. This
+ // is to handle very short files and provide parity with Chrome. See
+ // bug 1432195 for more information. This will not handle short files
+ // with a trailing tag, but as of writing we lack infrastructure to
+ // handle such tags.
+ MP3LOG(
+ "FindFirst() accepting candidate frame for short stream: "
+ "successiveFrames=%d",
+ numSuccFrames);
+ mFrameLock = true;
+ return candidateFrame;
+ }
+ }
+
+ MP3LOG("FindFirst() no suitable first frame found");
+ return candidateFrame;
+}
+
+static bool VerifyFrameConsistency(const FrameParser::Frame& aFrame1,
+ const FrameParser::Frame& aFrame2) {
+ const auto& h1 = aFrame1.Header();
+ const auto& h2 = aFrame2.Header();
+
+ return h1.IsValid() && h2.IsValid() && h1.Layer() == h2.Layer() &&
+ h1.SlotSize() == h2.SlotSize() &&
+ h1.SamplesPerFrame() == h2.SamplesPerFrame() &&
+ h1.Channels() == h2.Channels() && h1.SampleRate() == h2.SampleRate() &&
+ h1.RawVersion() == h2.RawVersion() &&
+ h1.RawProtection() == h2.RawProtection();
+}
+
+MediaByteRange MP3TrackDemuxer::FindNextFrame() {
+ static const int BUFFER_SIZE = 64;
+ static const uint32_t MAX_SKIPPABLE_BYTES = 1024 * BUFFER_SIZE;
+
+ MP3LOGV("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;
+ int64_t frameHeaderOffset = 0;
+ int64_t startOffset = mOffset;
+ const bool searchingForID3 = !mParser.ID3Header().HasSizeBeenSet();
+
+ // Check whether we've found a valid MPEG frame.
+ while (!foundFrame) {
+ // How many bytes we can go without finding a valid MPEG frame
+ // (effectively rounded up to the next full buffer size multiple, as we
+ // only check this before reading the next set of data into the buffer).
+
+ // This default value of 0 will be used during testing whether we're being
+ // fed a valid stream, which shouldn't have any gaps between frames.
+ uint32_t maxSkippableBytes = 0;
+
+ if (!mParser.FirstFrame().Length()) {
+ // We're looking for the first valid frame. A well-formed file should
+ // have its first frame header right at the start (skipping an ID3 tag
+ // if necessary), but in order to support files that might have been
+ // improperly cut, we search the first few kB for a frame header.
+ maxSkippableBytes = MAX_SKIPPABLE_BYTES;
+ // Since we're counting the skipped bytes from the offset we started
+ // this parsing session with, we need to discount the ID3 tag size only
+ // if we were looking for one during the current frame parsing session.
+ if (searchingForID3) {
+ maxSkippableBytes += mParser.TotalID3HeaderSize();
+ }
+ } else if (mFrameLock) {
+ // We've found a valid MPEG stream, so don't impose any limits
+ // to allow skipping corrupted data until we hit EOS.
+ maxSkippableBytes = std::numeric_limits<uint32_t>::max();
+ }
+
+ if ((mOffset - startOffset > maxSkippableBytes) ||
+ (read = Read(buffer, mOffset, BUFFER_SIZE)) == 0) {
+ MP3LOG(
+ "FindNext() EOS or exceeded maxSkippeableBytes without a frame "
+ "(read: %d)",
+ read);
+ // This is not a valid MPEG audio stream or we've reached EOS, give up.
+ break;
+ }
+
+ BufferReader reader(buffer, read);
+ uint32_t bytesToSkip = 0;
+ auto res = mParser.Parse(&reader, &bytesToSkip);
+ foundFrame = res.unwrapOr(false);
+ int64_t readerOffset = static_cast<int64_t>(reader.Offset());
+ frameHeaderOffset = mOffset + readerOffset - FrameParser::FrameHeader::SIZE;
+
+ // If we've found neither an MPEG frame header nor an ID3v2 tag,
+ // the reader shouldn't have any bytes remaining.
+ MOZ_ASSERT(foundFrame || bytesToSkip || !reader.Remaining());
+
+ if (foundFrame && mParser.FirstFrame().Length() &&
+ !VerifyFrameConsistency(mParser.FirstFrame(), mParser.CurrentFrame())) {
+ MP3LOG("Skipping frame");
+ // We've likely hit a false-positive, ignore it and proceed with the
+ // search for the next valid frame.
+ foundFrame = false;
+ mOffset = frameHeaderOffset + 1;
+ mParser.EndFrameSession();
+ } else {
+ // Advance mOffset by the amount of bytes read and if necessary,
+ // skip an ID3v2 tag which stretches beyond the current buffer.
+ NS_ENSURE_TRUE(mOffset + read + bytesToSkip > mOffset,
+ MediaByteRange(0, 0));
+ mOffset += static_cast<int64_t>(read + bytesToSkip);
+ }
+ }
+
+ if (StreamLength() != -1) {
+ mEOS = frameHeaderOffset + mParser.CurrentFrame().Length() + BUFFER_SIZE >
+ StreamLength();
+ }
+
+ if (!foundFrame || !mParser.CurrentFrame().Length()) {
+ MP3LOG("FindNext() Exit foundFrame=%d mParser.CurrentFrame().Length()=%d ",
+ foundFrame, mParser.CurrentFrame().Length());
+ return {0, 0};
+ }
+
+ MP3LOGV("FindNext() End mOffset=%" PRIu64 " mNumParsedFrames=%" PRIu64
+ " mFrameIndex=%" PRId64 " frameHeaderOffset=%" PRId64
+ " mTotalFrameLen=%" PRIu64
+ " mSamplesPerFrame=%d mSamplesPerSecond=%d"
+ " mChannels=%d, mEOS=%s",
+ mOffset, mNumParsedFrames, mFrameIndex, frameHeaderOffset,
+ mTotalFrameLen, mSamplesPerFrame, mSamplesPerSecond, mChannels,
+ mEOS ? "true" : "false");
+
+ return {frameHeaderOffset,
+ frameHeaderOffset + mParser.CurrentFrame().Length()};
+}
+
+bool MP3TrackDemuxer::SkipNextFrame(const MediaByteRange& aRange) {
+ if (!mNumParsedFrames || !aRange.Length()) {
+ // We can't skip the first frame, since it could contain VBR headers.
+ RefPtr<MediaRawData> frame(GetNextFrame(aRange));
+ return frame;
+ }
+
+ UpdateState(aRange);
+
+ MP3LOGV("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;
+}
+
+media::TimeUnit MP3TrackDemuxer::EncoderDelay() const {
+ return media::TimeUnit(mEncoderDelay, mSamplesPerSecond);
+}
+
+uint32_t MP3TrackDemuxer::EncoderDelayFrames() const { return mEncoderDelay; }
+
+media::TimeUnit MP3TrackDemuxer::Padding() const {
+ return media::TimeUnit(mEncoderPadding, mSamplesPerSecond);
+}
+
+uint32_t MP3TrackDemuxer::PaddingFrames() const { return mEncoderPadding; }
+
+already_AddRefed<MediaRawData> MP3TrackDemuxer::GetNextFrame(
+ const MediaByteRange& aRange) {
+ MP3LOG("GetNext() Begin({mStart=%" PRId64 " Length()=%" PRId64 "})",
+ aRange.mStart, aRange.Length());
+ if (!aRange.Length()) {
+ return nullptr;
+ }
+
+ RefPtr<MediaRawData> frame = new MediaRawData();
+ frame->mOffset = aRange.mStart;
+
+ UniquePtr<MediaRawDataWriter> frameWriter(frame->CreateWriter());
+ if (!frameWriter->SetSize(static_cast<size_t>(aRange.Length()))) {
+ MP3LOG("GetNext() Exit failed to allocated media buffer");
+ return nullptr;
+ }
+
+ const uint32_t read =
+ Read(frameWriter->Data(), frame->mOffset, frame->Size());
+
+ if (read != aRange.Length()) {
+ MP3LOG("GetNext() Exit read=%u frame->Size()=%zu", read, frame->Size());
+ return nullptr;
+ }
+
+ UpdateState(aRange);
+
+ if (mNumParsedFrames == 1) {
+ // First frame parsed, let's read VBR info if available.
+ BufferReader reader(frame->Data(), frame->Size());
+ mFirstFrameOffset = frame->mOffset;
+
+ if (mParser.ParseVBRHeader(&reader)) {
+ // Parsing was successful
+ if (mParser.VBRInfo().Type() == FrameParser::VBRHeader::XING) {
+ MP3LOG("XING header present, skipping encoder delay (%u frames)",
+ mParser.VBRInfo().EncoderDelay());
+ mEncoderDelay = mParser.VBRInfo().EncoderDelay();
+ mEncoderPadding = mParser.VBRInfo().EncoderPadding();
+ // Padding is encoded as a 12-bit unsigned number so this is fine.
+ mRemainingEncoderPadding = AssertedCast<int32_t>(mEncoderPadding);
+ if (mEncoderDelay == 0) {
+ // Skip the VBR frame + the decoder delay, that is always 529 frames
+ // in practice for the decoder we're using.
+ mEncoderDelay = mSamplesPerFrame + 529;
+ MP3LOG(
+ "No explicit delay present in vbr header, delay is assumed to be "
+ "%u frames\n",
+ mEncoderDelay);
+ }
+ } else if (mParser.VBRInfo().Type() == FrameParser::VBRHeader::VBRI) {
+ MP3LOG("VBRI header present, skipping encoder delay (%u frames)",
+ mParser.VBRInfo().EncoderDelay());
+ mEncoderDelay = mParser.VBRInfo().EncoderDelay();
+ }
+ }
+ }
+
+ TimeUnit rawPts = Duration(mFrameIndex - 1) - EncoderDelay();
+ TimeUnit rawDuration = Duration(1);
+ TimeUnit rawEnd = rawPts + rawDuration;
+
+ frame->mTime = std::max(TimeUnit::Zero(mSamplesPerSecond), rawPts);
+
+ frame->mDuration = Duration(1);
+ frame->mTimecode = frame->mTime;
+ frame->mKeyframe = true;
+ frame->mEOS = mEOS;
+
+ // 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(mSamplesPerSecond), rawEnd - frame->mTime);
+ }
+
+ // It's possible to create an mp3 file that has a padding value that somehow
+ // spans multiple packets. In that case the duration is probably known,
+ // because it's probably a VBR file with a XING header (that has a duration
+ // field). Use the duration to be able to set the correct duration on
+ // packets that aren't the last one.
+ // For most files, the padding is less than a packet, it's simply substracted.
+ if (mParser.VBRInfo().Type() == FrameParser::VBRHeader::XING &&
+ mRemainingEncoderPadding > 0 &&
+ frame->GetEndTime() > Duration().valueOr(TimeUnit::FromInfinity())) {
+ TimeUnit duration = Duration().value();
+ TimeUnit inPaddingZone = frame->GetEndTime() - duration;
+ TimeUnit originalEnd = frame->GetEndTime();
+ TimeUnit originalPts = frame->mTime;
+ frame->mDuration -= inPaddingZone;
+ // Packet is entirely padding and will be completely discarded by the
+ // decoder.
+ if (frame->mDuration.IsNegative()) {
+ frame->mDuration = TimeUnit::Zero(mSamplesPerSecond);
+ }
+ int32_t paddingFrames =
+ AssertedCast<int32_t>(inPaddingZone.ToTicksAtRate(mSamplesPerSecond));
+ if (mRemainingEncoderPadding >= paddingFrames) {
+ mRemainingEncoderPadding -= paddingFrames;
+ } else {
+ mRemainingEncoderPadding = 0;
+ }
+ MP3LOG("Trimming [%s, %s] to [%s,%s] (padding) (stream duration: %s)",
+ originalPts.ToString().get(), originalEnd.ToString().get(),
+ frame->mTime.ToString().get(), frame->GetEndTime().ToString().get(),
+ duration.ToString().get());
+ } else if (frame->mEOS &&
+ mRemainingEncoderPadding <=
+ frame->mDuration.ToTicksAtRate(mSamplesPerSecond)) {
+ frame->mDuration -= TimeUnit(mRemainingEncoderPadding, mSamplesPerSecond);
+ MOZ_ASSERT(frame->mDuration.IsPositiveOrZero());
+ MP3LOG("Trimming last packet %s to [%s,%s]", Padding().ToString().get(),
+ frame->mTime.ToString().get(), frame->GetEndTime().ToString().get());
+ }
+
+ MP3LOGV("GetNext() End mOffset=%" PRIu64 " mNumParsedFrames=%" PRIu64
+ " mFrameIndex=%" PRId64 " mTotalFrameLen=%" PRIu64
+ " mSamplesPerFrame=%d mSamplesPerSecond=%d mChannels=%d, mEOS=%s",
+ mOffset, mNumParsedFrames, mFrameIndex, mTotalFrameLen,
+ mSamplesPerFrame, mSamplesPerSecond, mChannels,
+ mEOS ? "true" : "false");
+
+ // It's possible for the duration of a frame to be zero if the frame is to be
+ // trimmed entirely because it's fully comprised of decoder delay samples.
+ // This is common at the beginning of an stream.
+ MOZ_ASSERT(frame->mDuration.IsPositiveOrZero());
+
+ MP3LOG("Packet demuxed: pts [%s, %s] (duration: %s)",
+ frame->mTime.ToString().get(), frame->GetEndTime().ToString().get(),
+ frame->mDuration.ToString().get());
+
+ // Indicate original packet information to trim after decoding.
+ if (frame->mDuration != rawDuration) {
+ frame->mOriginalPresentationWindow = Some(TimeInterval{rawPts, rawEnd});
+ MP3LOG("Total packet time excluding trimming: [%s, %s]",
+ rawPts.ToString().get(), rawEnd.ToString().get());
+ }
+
+ return frame.forget();
+}
+
+int64_t MP3TrackDemuxer::OffsetFromFrameIndex(int64_t aFrameIndex) const {
+ int64_t offset = 0;
+ const auto& vbr = mParser.VBRInfo();
+
+ if (vbr.IsComplete()) {
+ offset = mFirstFrameOffset + aFrameIndex * vbr.NumBytes().value() /
+ vbr.NumAudioFrames().value();
+ } else if (AverageFrameLength() > 0) {
+ offset = mFirstFrameOffset +
+ AssertedCast<int64_t>(static_cast<float>(aFrameIndex) *
+ AverageFrameLength());
+ }
+
+ MP3LOGV("OffsetFromFrameIndex(%" PRId64 ") -> %" PRId64, aFrameIndex, offset);
+ return std::max<int64_t>(mFirstFrameOffset, offset);
+}
+
+int64_t MP3TrackDemuxer::FrameIndexFromOffset(int64_t aOffset) const {
+ int64_t frameIndex = 0;
+ const auto& vbr = mParser.VBRInfo();
+
+ if (vbr.IsComplete()) {
+ frameIndex =
+ AssertedCast<int64_t>(static_cast<float>(aOffset - mFirstFrameOffset) /
+ static_cast<float>(vbr.NumBytes().value()) *
+ static_cast<float>(vbr.NumAudioFrames().value()));
+ frameIndex = std::min<int64_t>(vbr.NumAudioFrames().value(), frameIndex);
+ } else if (AverageFrameLength() > 0) {
+ frameIndex = AssertedCast<int64_t>(
+ static_cast<float>(aOffset - mFirstFrameOffset) / AverageFrameLength());
+ }
+
+ MP3LOGV("FrameIndexFromOffset(%" PRId64 ") -> %" PRId64, aOffset, frameIndex);
+ return std::max<int64_t>(0, frameIndex);
+}
+
+int64_t MP3TrackDemuxer::FrameIndexFromTime(
+ const media::TimeUnit& aTime) const {
+ int64_t frameIndex = 0;
+ if (mSamplesPerSecond > 0 && mSamplesPerFrame > 0) {
+ frameIndex = AssertedCast<int64_t>(
+ aTime.ToSeconds() * mSamplesPerSecond / mSamplesPerFrame - 1);
+ }
+
+ MP3LOGV("FrameIndexFromOffset(%fs) -> %" PRId64, aTime.ToSeconds(),
+ frameIndex);
+ return std::max<int64_t>(0, frameIndex);
+}
+
+void MP3TrackDemuxer::UpdateState(const MediaByteRange& aRange) {
+ // Prevent overflow.
+ if (mTotalFrameLen + aRange.Length() < 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 = aRange.mEnd;
+
+ mTotalFrameLen += aRange.Length();
+
+ if (!mSamplesPerFrame) {
+ mSamplesPerFrame = mParser.CurrentFrame().Header().SamplesPerFrame();
+ mSamplesPerSecond = mParser.CurrentFrame().Header().SampleRate();
+ mChannels = mParser.CurrentFrame().Header().Channels();
+ }
+
+ ++mNumParsedFrames;
+ ++mFrameIndex;
+ MOZ_ASSERT(mFrameIndex > 0);
+
+ // Prepare the parser for the next frame parsing session.
+ mParser.EndFrameSession();
+}
+
+uint32_t MP3TrackDemuxer::Read(uint8_t* aBuffer, int64_t aOffset,
+ uint32_t aSize) {
+ MP3LOGV("MP3TrackDemuxer::Read(%p %" PRId64 " %d)", aBuffer, aOffset, aSize);
+
+ const int64_t streamLen = StreamLength();
+ if (mInfo && streamLen > 0) {
+ // Prevent blocking reads after successful initialization.
+ int64_t max = streamLen > aOffset ? streamLen - aOffset : 0;
+ aSize = std::min<int64_t>(aSize, max);
+ }
+
+ uint32_t read = 0;
+ MP3LOGV("MP3TrackDemuxer::Read -> ReadAt(%u)", 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 MP3TrackDemuxer::AverageFrameLength() const {
+ if (mNumParsedFrames) {
+ return static_cast<double>(mTotalFrameLen) /
+ static_cast<double>(mNumParsedFrames);
+ }
+ const auto& vbr = mParser.VBRInfo();
+ if (vbr.IsComplete() && vbr.NumAudioFrames().value() + 1) {
+ return static_cast<double>(vbr.NumBytes().value()) /
+ (vbr.NumAudioFrames().value() + 1);
+ }
+ return 0.0;
+}
+
+Maybe<uint32_t> MP3TrackDemuxer::ValidNumAudioFrames() const {
+ return mParser.VBRInfo().IsValid() &&
+ mParser.VBRInfo().NumAudioFrames().valueOr(0) + 1 > 1
+ ? mParser.VBRInfo().NumAudioFrames()
+ : Nothing();
+}
+
+} // namespace mozilla
+
+#undef MP3LOG
+#undef MP3LOGV
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-25 03:11:41 +0000