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& new_buffers_cb,
  33                     const NewTextBuffersCB& text_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   void EmitNeedKeyIfNecessary(
  54       const std::vector<ProtectionSystemSpecificHeader>& headers);
  55
  56   // To retain proper framing, each 'mdat' atom must be read; to limit memory
  57   // usage, the atom's data needs to be discarded incrementally as frames are
  58   // extracted from the stream. This function discards data from the stream up
  59   // to |offset|, updating the |mdat_tail_| value so that framing can be
  60   // retained after all 'mdat' information has been read.
  61   // Returns 'true' on success, 'false' if there was an error.
  62   bool ReadAndDiscardMDATsUntil(const int64 offset);
  63
  64   void ChangeState(State new_state);
  65
  66   bool EmitConfigs();
  67   bool PrepareAVCBuffer(const AVCDecoderConfigurationRecord& avc_config,
  68                         std::vector<uint8>* frame_buf,
  69                         std::vector<SubsampleEntry>* subsamples) const;
  70   bool PrepareAACBuffer(const AAC& aac_config,
  71                         std::vector<uint8>* frame_buf,
  72                         std::vector<SubsampleEntry>* subsamples) const;
  73   bool EnqueueSample(BufferQueue* audio_buffers,
  74                      BufferQueue* video_buffers,
  75                      bool* err);
  76   bool SendAndFlushSamples(BufferQueue* audio_buffers,
  77                            BufferQueue* video_buffers);
  78
  79   void Reset();
  80
  81   State state_;
  82   InitCB init_cb_;
  83   NewConfigCB config_cb_;
  84   NewBuffersCB new_buffers_cb_;
  85   NeedKeyCB need_key_cb_;
  86   NewMediaSegmentCB new_segment_cb_;
  87   base::Closure end_of_segment_cb_;
  88   LogCB log_cb_;
  89
  90   OffsetByteQueue queue_;
  91
  92   // These two parameters are only valid in the |kEmittingSegments| state.
  93   //
  94   // |moof_head_| is the offset of the start of the most recently parsed moof
  95   // block. All byte offsets in sample information are relative to this offset,
  96   // as mandated by the Media Source spec.
  97   int64 moof_head_;
  98   // |mdat_tail_| is the stream offset of the end of the current 'mdat' box.
  99   // Valid iff it is greater than the head of the queue.
 100   int64 mdat_tail_;
 101
 102   scoped_ptr<mp4::Movie> moov_;
 103   scoped_ptr<mp4::TrackRunIterator> runs_;
 104
 105   bool has_audio_;
 106   bool has_video_;
 107   uint32 audio_track_id_;
 108   uint32 video_track_id_;
 109   // The object types allowed for audio tracks.
 110   std::set<int> audio_object_types_;
 111   bool has_sbr_;
 112   bool is_audio_track_encrypted_;
 113   bool is_video_track_encrypted_;
 114
 115   DISALLOW_COPY_AND_ASSIGN(MP4StreamParser);
 116 };
 117
 118 }  // namespace mp4
 119 }  // namespace media
 120
 121 #endif  // MEDIA_MP4_MP4_STREAM_PARSER_H_