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/* -*- 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/. */
#ifndef ADTS_DEMUXER_H_
#define ADTS_DEMUXER_H_
#include "mozilla/Attributes.h"
#include "mozilla/Maybe.h"
#include "MediaDataDemuxer.h"
#include "MediaResource.h"
namespace mozilla {
namespace adts {
class Frame;
class FrameParser;
} // namespace adts
class ADTSTrackDemuxer;
DDLoggedTypeDeclNameAndBase(ADTSDemuxer, MediaDataDemuxer);
class ADTSDemuxer : public MediaDataDemuxer,
public DecoderDoctorLifeLogger<ADTSDemuxer> {
public:
// MediaDataDemuxer interface.
explicit ADTSDemuxer(MediaResource* aSource);
RefPtr<InitPromise> Init() override;
uint32_t GetNumberTracks(TrackInfo::TrackType aType) const override;
already_AddRefed<MediaTrackDemuxer> GetTrackDemuxer(
TrackInfo::TrackType aType, uint32_t aTrackNumber) override;
bool IsSeekable() const override;
// Return true if a valid ADTS frame header could be found.
static bool ADTSSniffer(const uint8_t* aData, const uint32_t aLength);
private:
bool InitInternal();
RefPtr<MediaResource> mSource;
RefPtr<ADTSTrackDemuxer> mTrackDemuxer;
};
DDLoggedTypeNameAndBase(ADTSTrackDemuxer, MediaTrackDemuxer);
class ADTSTrackDemuxer : public MediaTrackDemuxer,
public DecoderDoctorLifeLogger<ADTSTrackDemuxer> {
public:
explicit ADTSTrackDemuxer(MediaResource* aSource);
// Initializes the track demuxer by reading the first frame for meta data.
// Returns initialization success state.
bool Init();
// Returns the total stream length if known, -1 otherwise.
int64_t StreamLength() const;
// Returns the estimated stream duration, or a 0-duration if unknown.
media::TimeUnit Duration() const;
// Returns the estimated duration up to the given frame number,
// or a 0-duration if unknown.
media::TimeUnit Duration(int64_t aNumFrames) const;
// MediaTrackDemuxer interface.
UniquePtr<TrackInfo> GetInfo() const override;
RefPtr<SeekPromise> Seek(const media::TimeUnit& aTime) override;
RefPtr<SamplesPromise> GetSamples(int32_t aNumSamples = 1) override;
void Reset() override;
RefPtr<SkipAccessPointPromise> SkipToNextRandomAccessPoint(
const media::TimeUnit& aTimeThreshold) override;
int64_t GetResourceOffset() const override;
media::TimeIntervals GetBuffered() override;
private:
// Destructor.
~ADTSTrackDemuxer();
// Fast approximate seeking to given time.
media::TimeUnit FastSeek(const media::TimeUnit& aTime);
// Seeks by scanning the stream up to the given time for more accurate
// results.
media::TimeUnit ScanUntil(const media::TimeUnit& aTime);
// Finds the next valid frame and returns its byte range.
const adts::Frame& FindNextFrame(bool findFirstFrame = false);
// Skips the next frame given the provided byte range.
bool SkipNextFrame(const adts::Frame& aFrame);
// Returns the next ADTS frame, if available.
already_AddRefed<MediaRawData> GetNextFrame(const adts::Frame& aFrame);
// Updates post-read meta data.
void UpdateState(const adts::Frame& aFrame);
// Returns the frame index for the given offset.
int64_t FrameIndexFromOffset(int64_t aOffset) const;
// Returns the frame index for the given time.
int64_t FrameIndexFromTime(const media::TimeUnit& aTime) const;
// Reads aSize bytes into aBuffer from the source starting at aOffset.
// Returns the actual size read.
int32_t Read(uint8_t* aBuffer, int64_t aOffset, int32_t aSize);
// Returns the average frame length derived from the previously parsed frames.
double AverageFrameLength() const;
// The (hopefully) ADTS resource.
MediaResourceIndex mSource;
// ADTS frame parser used to detect frames and extract side info.
adts::FrameParser* mParser;
// Current byte offset in the source stream.
int64_t mOffset;
// Total parsed frames.
uint64_t mNumParsedFrames;
// Current frame index.
int64_t mFrameIndex;
// Sum of parsed frames' lengths in bytes.
uint64_t mTotalFrameLen;
// Samples per frame metric derived from frame headers or 0 if none available.
uint32_t mSamplesPerFrame;
// Samples per second metric derived from frame headers or 0 if none
// available.
uint32_t mSamplesPerSecond;
// Channel count derived from frame headers or 0 if none available.
uint32_t mChannels;
// Audio track config info.
UniquePtr<AudioInfo> mInfo;
// Amount of pre-roll time when seeking.
// AAC encoder delay is by default 2112 audio frames.
media::TimeUnit mPreRoll;
};
} // namespace mozilla
#endif // !ADTS_DEMUXER_H_