1 /* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef A_TS_PARSER_H_ 18 19 #define A_TS_PARSER_H_ 20 21 #include <sys/types.h> 22 23 #include <media/stagefright/foundation/ABase.h> 24 #include <media/stagefright/foundation/AMessage.h> 25 #include <media/stagefright/MediaSource.h> 26 #include <utils/KeyedVector.h> 27 #include <utils/Vector.h> 28 #include <utils/RefBase.h> 29 30 namespace android { 31 32 class ABitReader; 33 struct ABuffer; 34 35 struct ATSParser : public RefBase { 36 enum DiscontinuityType { 37 DISCONTINUITY_NONE = 0, 38 DISCONTINUITY_TIME = 1, 39 DISCONTINUITY_AUDIO_FORMAT = 2, 40 DISCONTINUITY_VIDEO_FORMAT = 4, 41 DISCONTINUITY_ABSOLUTE_TIME = 8, 42 DISCONTINUITY_TIME_OFFSET = 16, 43 44 // For legacy reasons this also implies a time discontinuity. 45 DISCONTINUITY_FORMATCHANGE = 46 DISCONTINUITY_AUDIO_FORMAT 47 | DISCONTINUITY_VIDEO_FORMAT 48 | DISCONTINUITY_TIME, 49 DISCONTINUITY_FORMAT_ONLY = 50 DISCONTINUITY_AUDIO_FORMAT 51 | DISCONTINUITY_VIDEO_FORMAT, 52 }; 53 54 enum Flags { 55 // The 90kHz clock (PTS/DTS) is absolute, i.e. PTS=0 corresponds to 56 // a media time of 0. 57 // If this flag is _not_ specified, the first PTS encountered in a 58 // program of this stream will be assumed to correspond to media time 0 59 // instead. 60 TS_TIMESTAMPS_ARE_ABSOLUTE = 1, 61 // Video PES packets contain exactly one (aligned) access unit. 62 ALIGNED_VIDEO_DATA = 2, 63 }; 64 65 // Event is used to signal sync point event at feedTSPacket(). 66 struct SyncEvent { 67 SyncEvent(off64_t offset); 68 69 void init(off64_t offset, const sp<MediaSource> &source, 70 int64_t timeUs); 71 isInitATSParser::SyncEvent72 bool isInit() { return mInit; } getOffsetATSParser::SyncEvent73 off64_t getOffset() { return mOffset; } getMediaSourceATSParser::SyncEvent74 const sp<MediaSource> &getMediaSource() { return mMediaSource; } getTimeUsATSParser::SyncEvent75 int64_t getTimeUs() { return mTimeUs; } 76 77 private: 78 bool mInit; 79 /* 80 * mInit == false: the current offset 81 * mInit == true: the start offset of sync payload 82 */ 83 off64_t mOffset; 84 /* The media source object for this event. */ 85 sp<MediaSource> mMediaSource; 86 /* The timestamp of the sync frame. */ 87 int64_t mTimeUs; 88 }; 89 90 ATSParser(uint32_t flags = 0); 91 92 // Feed a TS packet into the parser. uninitialized event with the start 93 // offset of this TS packet goes in, and if the parser detects PES with 94 // a sync frame, the event will be initiailzed with the start offset of the 95 // PES. Note that the offset of the event can be different from what we fed, 96 // as a PES may consist of multiple TS packets. 97 // 98 // Even in the case feedTSPacket() returns non-OK value, event still may be 99 // initialized if the parsing failed after the detection. 100 status_t feedTSPacket( 101 const void *data, size_t size, SyncEvent *event = NULL); 102 103 void signalDiscontinuity( 104 DiscontinuityType type, const sp<AMessage> &extra); 105 106 void signalEOS(status_t finalResult); 107 108 enum SourceType { 109 VIDEO = 0, 110 AUDIO = 1, 111 META = 2, 112 NUM_SOURCE_TYPES = 3 113 }; 114 sp<MediaSource> getSource(SourceType type); 115 bool hasSource(SourceType type) const; 116 117 bool PTSTimeDeltaEstablished(); 118 119 enum { 120 // From ISO/IEC 13818-1: 2000 (E), Table 2-29 121 STREAMTYPE_RESERVED = 0x00, 122 STREAMTYPE_MPEG1_VIDEO = 0x01, 123 STREAMTYPE_MPEG2_VIDEO = 0x02, 124 STREAMTYPE_MPEG1_AUDIO = 0x03, 125 STREAMTYPE_MPEG2_AUDIO = 0x04, 126 STREAMTYPE_MPEG2_AUDIO_ADTS = 0x0f, 127 STREAMTYPE_MPEG4_VIDEO = 0x10, 128 STREAMTYPE_METADATA = 0x15, 129 STREAMTYPE_H264 = 0x1b, 130 131 // From ATSC A/53 Part 3:2009, 6.7.1 132 STREAMTYPE_AC3 = 0x81, 133 134 // Stream type 0x83 is non-standard, 135 // it could be LPCM or TrueHD AC3 136 STREAMTYPE_LPCM_AC3 = 0x83, 137 }; 138 139 protected: 140 virtual ~ATSParser(); 141 142 private: 143 struct Program; 144 struct Stream; 145 struct PSISection; 146 147 uint32_t mFlags; 148 Vector<sp<Program> > mPrograms; 149 150 // Keyed by PID 151 KeyedVector<unsigned, sp<PSISection> > mPSISections; 152 153 int64_t mAbsoluteTimeAnchorUs; 154 155 bool mTimeOffsetValid; 156 int64_t mTimeOffsetUs; 157 int64_t mLastRecoveredPTS; 158 159 size_t mNumTSPacketsParsed; 160 161 void parseProgramAssociationTable(ABitReader *br); 162 void parseProgramMap(ABitReader *br); 163 // Parse PES packet where br is pointing to. If the PES contains a sync 164 // frame, set event with the time and the start offset of this PES. 165 // Note that the method itself does not touch event. 166 void parsePES(ABitReader *br, SyncEvent *event); 167 168 // Strip remaining packet headers and pass to appropriate program/stream 169 // to parse the payload. If the payload turns out to be PES and contains 170 // a sync frame, event shall be set with the time and start offset of the 171 // PES. 172 // Note that the method itself does not touch event. 173 status_t parsePID( 174 ABitReader *br, unsigned PID, 175 unsigned continuity_counter, 176 unsigned payload_unit_start_indicator, 177 SyncEvent *event); 178 179 status_t parseAdaptationField(ABitReader *br, unsigned PID); 180 // see feedTSPacket(). 181 status_t parseTS(ABitReader *br, SyncEvent *event); 182 183 void updatePCR(unsigned PID, uint64_t PCR, size_t byteOffsetFromStart); 184 185 uint64_t mPCR[2]; 186 size_t mPCRBytes[2]; 187 int64_t mSystemTimeUs[2]; 188 size_t mNumPCRs; 189 190 DISALLOW_EVIL_CONSTRUCTORS(ATSParser); 191 }; 192 193 } // namespace android 194 195 #endif // A_TS_PARSER_H_ 196