1 // Copyright 2014 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_FORMATS_MP4_MP4_STREAM_PARSER_H_ 6 #define MEDIA_FORMATS_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/formats/common/offset_byte_queue.h" 18 #include "media/formats/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 bool ignore_text_tracks, 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 kWaitingForSampleData, 46 kEmittingSamples, 47 kError 48 }; 49 50 bool ParseBox(bool* err); 51 bool ParseMoov(mp4::BoxReader* reader); 52 bool ParseMoof(mp4::BoxReader* reader); 53 54 void 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 |max_clear_offset|, updating the |mdat_tail_| value so that framing can 61 // be retained after all 'mdat' information has been read. |max_clear_offset| 62 // is the upper bound on what can be removed from |queue_|. Anything below 63 // this offset is no longer needed by the parser. 64 // Returns 'true' on success, 'false' if there was an error. 65 bool ReadAndDiscardMDATsUntil(int64 max_clear_offset); 66 67 void ChangeState(State new_state); 68 69 bool EmitConfigs(); 70 bool PrepareAVCBuffer(const AVCDecoderConfigurationRecord& avc_config, 71 std::vector<uint8>* frame_buf, 72 std::vector<SubsampleEntry>* subsamples) const; 73 bool PrepareAACBuffer(const AAC& aac_config, 74 std::vector<uint8>* frame_buf, 75 std::vector<SubsampleEntry>* subsamples) const; 76 bool EnqueueSample(BufferQueue* audio_buffers, 77 BufferQueue* video_buffers, 78 bool* err); 79 bool SendAndFlushSamples(BufferQueue* audio_buffers, 80 BufferQueue* video_buffers); 81 82 void Reset(); 83 84 // Checks to see if we have enough data in |queue_| to transition to 85 // kEmittingSamples and start enqueuing samples. 86 bool HaveEnoughDataToEnqueueSamples(); 87 88 // Sets |highest_end_offset_| based on the data in |moov_| 89 // and |moof|. Returns true if |highest_end_offset_| was successfully 90 // computed. 91 bool ComputeHighestEndOffset(const MovieFragment& moof); 92 93 State state_; 94 InitCB init_cb_; 95 NewConfigCB config_cb_; 96 NewBuffersCB new_buffers_cb_; 97 NeedKeyCB need_key_cb_; 98 NewMediaSegmentCB new_segment_cb_; 99 base::Closure end_of_segment_cb_; 100 LogCB log_cb_; 101 102 OffsetByteQueue queue_; 103 104 // These two parameters are only valid in the |kEmittingSegments| state. 105 // 106 // |moof_head_| is the offset of the start of the most recently parsed moof 107 // block. All byte offsets in sample information are relative to this offset, 108 // as mandated by the Media Source spec. 109 int64 moof_head_; 110 // |mdat_tail_| is the stream offset of the end of the current 'mdat' box. 111 // Valid iff it is greater than the head of the queue. 112 int64 mdat_tail_; 113 114 // The highest end offset in the current moof. This offset is 115 // relative to |moof_head_|. This value is used to make sure we have collected 116 // enough bytes to parse all samples and aux_info in the current moof. 117 int64 highest_end_offset_; 118 119 scoped_ptr<mp4::Movie> moov_; 120 scoped_ptr<mp4::TrackRunIterator> runs_; 121 122 bool has_audio_; 123 bool has_video_; 124 uint32 audio_track_id_; 125 uint32 video_track_id_; 126 // The object types allowed for audio tracks. 127 std::set<int> audio_object_types_; 128 bool has_sbr_; 129 bool is_audio_track_encrypted_; 130 bool is_video_track_encrypted_; 131 132 DISALLOW_COPY_AND_ASSIGN(MP4StreamParser); 133 }; 134 135 } // namespace mp4 136 } // namespace media 137 138 #endif // MEDIA_FORMATS_MP4_MP4_STREAM_PARSER_H_ 139