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 hasReturnedDataATSParser::SyncEvent72 bool hasReturnedData() const { return mHasReturnedData; } 73 void reset(); getOffsetATSParser::SyncEvent74 off64_t getOffset() const { return mOffset; } getMediaSourceATSParser::SyncEvent75 const sp<MediaSource> &getMediaSource() const { return mMediaSource; } getTimeUsATSParser::SyncEvent76 int64_t getTimeUs() const { return mTimeUs; } 77 78 private: 79 bool mHasReturnedData; 80 /* 81 * mHasReturnedData == false: the current offset (or undefined if the returned data 82 has been invalidated via reset()) 83 * mHasReturnedData == true: the start offset of sync payload 84 */ 85 off64_t mOffset; 86 /* The media source object for this event. */ 87 sp<MediaSource> mMediaSource; 88 /* The timestamp of the sync frame. */ 89 int64_t mTimeUs; 90 }; 91 92 ATSParser(uint32_t flags = 0); 93 94 // Feed a TS packet into the parser. uninitialized event with the start 95 // offset of this TS packet goes in, and if the parser detects PES with 96 // a sync frame, the event will be initiailzed with the start offset of the 97 // PES. Note that the offset of the event can be different from what we fed, 98 // as a PES may consist of multiple TS packets. 99 // 100 // Even in the case feedTSPacket() returns non-OK value, event still may be 101 // initialized if the parsing failed after the detection. 102 status_t feedTSPacket( 103 const void *data, size_t size, SyncEvent *event = NULL); 104 105 void signalDiscontinuity( 106 DiscontinuityType type, const sp<AMessage> &extra); 107 108 void signalEOS(status_t finalResult); 109 110 enum SourceType { 111 VIDEO = 0, 112 AUDIO = 1, 113 META = 2, 114 NUM_SOURCE_TYPES = 3 115 }; 116 sp<MediaSource> getSource(SourceType type); 117 bool hasSource(SourceType type) const; 118 119 bool PTSTimeDeltaEstablished(); 120 121 enum { 122 // From ISO/IEC 13818-1: 2000 (E), Table 2-29 123 STREAMTYPE_RESERVED = 0x00, 124 STREAMTYPE_MPEG1_VIDEO = 0x01, 125 STREAMTYPE_MPEG2_VIDEO = 0x02, 126 STREAMTYPE_MPEG1_AUDIO = 0x03, 127 STREAMTYPE_MPEG2_AUDIO = 0x04, 128 STREAMTYPE_MPEG2_AUDIO_ADTS = 0x0f, 129 STREAMTYPE_MPEG4_VIDEO = 0x10, 130 STREAMTYPE_METADATA = 0x15, 131 STREAMTYPE_H264 = 0x1b, 132 133 // From ATSC A/53 Part 3:2009, 6.7.1 134 STREAMTYPE_AC3 = 0x81, 135 136 // Stream type 0x83 is non-standard, 137 // it could be LPCM or TrueHD AC3 138 STREAMTYPE_LPCM_AC3 = 0x83, 139 }; 140 141 protected: 142 virtual ~ATSParser(); 143 144 private: 145 struct Program; 146 struct Stream; 147 struct PSISection; 148 149 uint32_t mFlags; 150 Vector<sp<Program> > mPrograms; 151 152 // Keyed by PID 153 KeyedVector<unsigned, sp<PSISection> > mPSISections; 154 155 int64_t mAbsoluteTimeAnchorUs; 156 157 bool mTimeOffsetValid; 158 int64_t mTimeOffsetUs; 159 int64_t mLastRecoveredPTS; 160 161 size_t mNumTSPacketsParsed; 162 163 void parseProgramAssociationTable(ABitReader *br); 164 void parseProgramMap(ABitReader *br); 165 // Parse PES packet where br is pointing to. If the PES contains a sync 166 // frame, set event with the time and the start offset of this PES. 167 // Note that the method itself does not touch event. 168 void parsePES(ABitReader *br, SyncEvent *event); 169 170 // Strip remaining packet headers and pass to appropriate program/stream 171 // to parse the payload. If the payload turns out to be PES and contains 172 // a sync frame, event shall be set with the time and start offset of the 173 // PES. 174 // Note that the method itself does not touch event. 175 status_t parsePID( 176 ABitReader *br, unsigned PID, 177 unsigned continuity_counter, 178 unsigned payload_unit_start_indicator, 179 SyncEvent *event); 180 181 status_t parseAdaptationField(ABitReader *br, unsigned PID); 182 // see feedTSPacket(). 183 status_t parseTS(ABitReader *br, SyncEvent *event); 184 185 void updatePCR(unsigned PID, uint64_t PCR, uint64_t byteOffsetFromStart); 186 187 uint64_t mPCR[2]; 188 uint64_t mPCRBytes[2]; 189 int64_t mSystemTimeUs[2]; 190 size_t mNumPCRs; 191 192 DISALLOW_EVIL_CONSTRUCTORS(ATSParser); 193 }; 194 195 } // namespace android 196 197 #endif // A_TS_PARSER_H_ 198