dom/media/flac/FlacDemuxer.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef FLAC_DEMUXER_H_
   8 #define FLAC_DEMUXER_H_
   9
  10 #include "mozilla/Attributes.h"
  11 #include "MediaDataDemuxer.h"
  12 #include "MediaResource.h"
  13 namespace mozilla {
  14
  15 namespace flac {
  16 class Frame;
  17 class FrameParser;
  18 }  // namespace flac
  19 class FlacTrackDemuxer;
  20
  21 DDLoggedTypeDeclNameAndBase(FlacDemuxer, MediaDataDemuxer);
  22 DDLoggedTypeNameAndBase(FlacTrackDemuxer, MediaTrackDemuxer);
  23
  24 class FlacDemuxer : public MediaDataDemuxer,
  25                     public DecoderDoctorLifeLogger<FlacDemuxer> {
  26  public:
  27   // MediaDataDemuxer interface.
  28   explicit FlacDemuxer(MediaResource* aSource);
  29   RefPtr<InitPromise> Init() override;
  30   uint32_t GetNumberTracks(TrackInfo::TrackType aType) const override;
  31   already_AddRefed<MediaTrackDemuxer> GetTrackDemuxer(
  32       TrackInfo::TrackType aType, uint32_t aTrackNumber) override;
  33   bool IsSeekable() const override;
  34
  35   // Return true if a valid flac frame header could be found.
  36   static bool FlacSniffer(const uint8_t* aData, const uint32_t aLength);
  37
  38  private:
  39   bool InitInternal();
  40
  41   RefPtr<MediaResource> mSource;
  42   RefPtr<FlacTrackDemuxer> mTrackDemuxer;
  43 };
  44
  45 class FlacTrackDemuxer : public MediaTrackDemuxer,
  46                          public DecoderDoctorLifeLogger<FlacTrackDemuxer> {
  47  public:
  48   explicit FlacTrackDemuxer(MediaResource* aSource);
  49
  50   // Initializes the track demuxer by reading the first frame for meta data.
  51   // Returns initialization success state.
  52   bool Init();
  53
  54   // MediaTrackDemuxer interface.
  55   UniquePtr<TrackInfo> GetInfo() const override;
  56   RefPtr<SeekPromise> Seek(const media::TimeUnit& aTime) override;
  57   RefPtr<SamplesPromise> GetSamples(int32_t aNumSamples = 1) override;
  58   void Reset() override;
  59   int64_t GetResourceOffset() const override;
  60   media::TimeIntervals GetBuffered() override;
  61   RefPtr<SkipAccessPointPromise> SkipToNextRandomAccessPoint(
  62       const media::TimeUnit& aTimeThreshold) override;
  63
  64   bool IsSeekable() const;
  65
  66  private:
  67   // Destructor.
  68   ~FlacTrackDemuxer();
  69
  70   // Returns the estimated stream duration, or a 0-duration if unknown.
  71   media::TimeUnit Duration() const;
  72   media::TimeUnit TimeAtEnd();
  73
  74   // Fast approximate seeking to given time.
  75   media::TimeUnit FastSeek(const media::TimeUnit& aTime);
  76
  77   // Seeks by scanning the stream up to the given time for more accurate
  78   // results.
  79   media::TimeUnit ScanUntil(const media::TimeUnit& aTime);
  80
  81   // Finds the next valid frame and return it.
  82   const flac::Frame& FindNextFrame();
  83
  84   // Returns the next ADTS frame, if available.
  85   already_AddRefed<MediaRawData> GetNextFrame(const flac::Frame& aFrame);
  86
  87   // Reads aSize bytes into aBuffer from the source starting at aOffset.
  88   // Returns the actual size read.
  89   uint32_t Read(uint8_t* aBuffer, int64_t aOffset, int32_t aSize);
  90
  91   // Returns the average frame length derived from the previously parsed frames.
  92   double AverageFrameLength() const;
  93
  94   // The (hopefully) Flac resource.
  95   MediaResourceIndex mSource;
  96
  97   // Flac frame parser used to detect frames and extract side info.
  98   UniquePtr<flac::FrameParser> mParser;
  99
 100   // Total duration of parsed frames.
 101   media::TimeUnit mParsedFramesDuration;
 102
 103   // Sum of parsed frames' lengths in bytes.
 104   uint64_t mTotalFrameLen;
 105
 106   // Audio track config info.
 107   UniquePtr<AudioInfo> mInfo;
 108 };
 109
 110 }  // namespace mozilla
 111
 112 #endif  // !FLAC_DEMUXER_H_