media/mp4/mp4_stream_parser.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef MEDIA_MP4_MP4_STREAM_PARSER_H_
   6 #define MEDIA_MP4_MP4_STREAM_PARSER_H_
   7
   8 #include <set>
   9 #include <vector>
  10
  11 #include "base/basictypes.h"
  12 #include "base/callback.h"
  13 #include "base/compiler_specific.h"
  14 #include "base/memory/scoped_ptr.h"
  15 #include "media/base/media_export.h"
  16 #include "media/base/stream_parser.h"
  17 #include "media/mp4/offset_byte_queue.h"
  18 #include "media/mp4/track_run_iterator.h"
  19
  20 namespace media {
  21 namespace mp4 {
  22
  23 struct Movie;
  24 class BoxReader;
  25
  26 class MEDIA_EXPORT MP4StreamParser : public StreamParser {
  27  public:
  28   MP4StreamParser(const std::set<int>& audio_object_types, bool has_sbr);
  29   virtual ~MP4StreamParser();
  30
  31   virtual void Init(const InitCB& init_cb, const NewConfigCB& config_cb,
  32                     const NewBuffersCB& audio_cb,
  33                     const NewBuffersCB& video_cb,
  34                     const NeedKeyCB& need_key_cb,
  35                     const NewMediaSegmentCB& new_segment_cb,
  36                     const base::Closure& end_of_segment_cb,
  37                     const LogCB& log_cb) OVERRIDE;
  38   virtual void Flush() OVERRIDE;
  39   virtual bool Parse(const uint8* buf, int size) OVERRIDE;
  40
  41  private:
  42   enum State {
  43     kWaitingForInit,
  44     kParsingBoxes,
  45     kEmittingSamples,
  46     kError
  47   };
  48
  49   bool ParseBox(bool* err);
  50   bool ParseMoov(mp4::BoxReader* reader);
  51   bool ParseMoof(mp4::BoxReader* reader);
  52
  53   // Returns 'true' if sent or not required, 'false' if there was an error.
  54   bool EmitNeedKeyIfNecessary(
  55       const std::vector<ProtectionSystemSpecificHeader>& headers);
  56
  57   // To retain proper framing, each 'mdat' atom must be read; to limit memory
  58   // usage, the atom's data needs to be discarded incrementally as frames are
  59   // extracted from the stream. This function discards data from the stream up
  60   // to |offset|, updating the |mdat_tail_| value so that framing can be
  61   // retained after all 'mdat' information has been read.
  62   // Returns 'true' on success, 'false' if there was an error.
  63   bool ReadAndDiscardMDATsUntil(const int64 offset);
  64
  65   void ChangeState(State new_state);
  66
  67   bool EmitConfigs();
  68   bool PrepareAVCBuffer(const AVCDecoderConfigurationRecord& avc_config,
  69                         std::vector<uint8>* frame_buf,
  70                         std::vector<SubsampleEntry>* subsamples) const;
  71   bool PrepareAACBuffer(const AAC& aac_config,
  72                         std::vector<uint8>* frame_buf,
  73                         std::vector<SubsampleEntry>* subsamples) const;
  74   bool EnqueueSample(BufferQueue* audio_buffers,
  75                      BufferQueue* video_buffers,
  76                      bool* err);
  77   bool SendAndFlushSamples(BufferQueue* audio_buffers,
  78                            BufferQueue* video_buffers);
  79
  80   void Reset();
  81
  82   State state_;
  83   InitCB init_cb_;
  84   NewConfigCB config_cb_;
  85   NewBuffersCB audio_cb_;
  86   NewBuffersCB video_cb_;
  87   NeedKeyCB need_key_cb_;
  88   NewMediaSegmentCB new_segment_cb_;
  89   base::Closure end_of_segment_cb_;
  90   LogCB log_cb_;
  91
  92   OffsetByteQueue queue_;
  93
  94   // These two parameters are only valid in the |kEmittingSegments| state.
  95   //
  96   // |moof_head_| is the offset of the start of the most recently parsed moof
  97   // block. All byte offsets in sample information are relative to this offset,
  98   // as mandated by the Media Source spec.
  99   int64 moof_head_;
 100   // |mdat_tail_| is the stream offset of the end of the current 'mdat' box.
 101   // Valid iff it is greater than the head of the queue.
 102   int64 mdat_tail_;
 103
 104   scoped_ptr<mp4::Movie> moov_;
 105   scoped_ptr<mp4::TrackRunIterator> runs_;
 106
 107   bool has_audio_;
 108   bool has_video_;
 109   uint32 audio_track_id_;
 110   uint32 video_track_id_;
 111   // The object types allowed for audio tracks.
 112   std::set<int> audio_object_types_;
 113   bool has_sbr_;
 114   bool is_audio_track_encrypted_;
 115   bool is_video_track_encrypted_;
 116
 117   DISALLOW_COPY_AND_ASSIGN(MP4StreamParser);
 118 };
 119
 120 }  // namespace mp4
 121 }  // namespace media
 122
 123 #endif  // MEDIA_MP4_MP4_STREAM_PARSER_H_