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/MediaSource.h>
24 #include <media/stagefright/foundation/ABase.h>
25 #include <media/stagefright/foundation/AMessage.h>
26 #include <media/stagefright/foundation/AudioPresentationInfo.h>
27 #include <utils/KeyedVector.h>
28 #include <utils/Vector.h>
29 #include <utils/RefBase.h>
30 #include <vector>
31 
32 namespace android {
33 namespace hardware {
34 namespace cas {
35 namespace V1_0 {
36 struct ICas;
37 }}}
38 using hardware::cas::V1_0::ICas;
39 
40 class ABitReader;
41 struct ABuffer;
42 struct AnotherPacketSource;
43 
44 struct ATSParser : public RefBase {
45     enum DiscontinuityType {
46         DISCONTINUITY_NONE              = 0,
47         DISCONTINUITY_TIME              = 1,
48         DISCONTINUITY_AUDIO_FORMAT      = 2,
49         DISCONTINUITY_VIDEO_FORMAT      = 4,
50         DISCONTINUITY_ABSOLUTE_TIME     = 8,
51         DISCONTINUITY_TIME_OFFSET       = 16,
52 
53         // For legacy reasons this also implies a time discontinuity.
54         DISCONTINUITY_FORMATCHANGE      =
55             DISCONTINUITY_AUDIO_FORMAT
56                 | DISCONTINUITY_VIDEO_FORMAT
57                 | DISCONTINUITY_TIME,
58         DISCONTINUITY_FORMAT_ONLY       =
59             DISCONTINUITY_AUDIO_FORMAT
60                 | DISCONTINUITY_VIDEO_FORMAT,
61     };
62 
63     enum Flags {
64         // The 90kHz clock (PTS/DTS) is absolute, i.e. PTS=0 corresponds to
65         // a media time of 0.
66         // If this flag is _not_ specified, the first PTS encountered in a
67         // program of this stream will be assumed to correspond to media time 0
68         // instead.
69         TS_TIMESTAMPS_ARE_ABSOLUTE = 1,
70         // Video PES packets contain exactly one (aligned) access unit.
71         ALIGNED_VIDEO_DATA         = 2,
72     };
73 
74     enum SourceType {
75         VIDEO = 0,
76         AUDIO = 1,
77         META  = 2,
78         NUM_SOURCE_TYPES = 3
79     };
80 
81     // Event is used to signal sync point event at feedTSPacket().
82     struct SyncEvent {
83         explicit SyncEvent(off64_t offset);
84 
85         void init(off64_t offset, const sp<AnotherPacketSource> &source,
86                 int64_t timeUs, SourceType type);
87 
hasReturnedDataATSParser::SyncEvent88         bool hasReturnedData() const { return mHasReturnedData; }
89         void reset();
getOffsetATSParser::SyncEvent90         off64_t getOffset() const { return mOffset; }
getMediaSourceATSParser::SyncEvent91         const sp<AnotherPacketSource> &getMediaSource() const { return mMediaSource; }
getTimeUsATSParser::SyncEvent92         int64_t getTimeUs() const { return mTimeUs; }
getTypeATSParser::SyncEvent93         SourceType getType() const { return mType; }
94 
95     private:
96         bool mHasReturnedData;
97         /*
98          * mHasReturnedData == false: the current offset (or undefined if the returned data
99                                       has been invalidated via reset())
100          * mHasReturnedData == true: the start offset of sync payload
101          */
102         off64_t mOffset;
103         /* The media source object for this event. */
104         sp<AnotherPacketSource> mMediaSource;
105         /* The timestamp of the sync frame. */
106         int64_t mTimeUs;
107         SourceType mType;
108     };
109 
110     explicit ATSParser(uint32_t flags = 0);
111 
112     status_t setMediaCas(const sp<ICas> &cas);
113 
114     // Feed a TS packet into the parser. uninitialized event with the start
115     // offset of this TS packet goes in, and if the parser detects PES with
116     // a sync frame, the event will be initiailzed with the start offset of the
117     // PES. Note that the offset of the event can be different from what we fed,
118     // as a PES may consist of multiple TS packets.
119     //
120     // Even in the case feedTSPacket() returns non-OK value, event still may be
121     // initialized if the parsing failed after the detection.
122     status_t feedTSPacket(
123             const void *data, size_t size, SyncEvent *event = NULL);
124 
125     void signalDiscontinuity(
126             DiscontinuityType type, const sp<AMessage> &extra);
127 
128     void signalEOS(status_t finalResult);
129 
130     sp<AnotherPacketSource> getSource(SourceType type);
131     bool hasSource(SourceType type) const;
132 
133     bool PTSTimeDeltaEstablished();
134 
135     int64_t getFirstPTSTimeUs();
136 
137     void signalNewSampleAesKey(const sp<AMessage> &keyItem);
138 
139     enum {
140         // From ISO/IEC 13818-1: 2000 (E), Table 2-29
141         STREAMTYPE_RESERVED             = 0x00,
142         STREAMTYPE_MPEG1_VIDEO          = 0x01,
143         STREAMTYPE_MPEG2_VIDEO          = 0x02,
144         STREAMTYPE_MPEG1_AUDIO          = 0x03,
145         STREAMTYPE_MPEG2_AUDIO          = 0x04,
146         STREAMTYPE_PES_PRIVATE_DATA     = 0x06,
147         STREAMTYPE_MPEG2_AUDIO_ADTS     = 0x0f,
148         STREAMTYPE_MPEG4_VIDEO          = 0x10,
149         STREAMTYPE_METADATA             = 0x15,
150         STREAMTYPE_H264                 = 0x1b,
151 
152         // From ATSC A/53 Part 3:2009, 6.7.1
153         STREAMTYPE_AC3                  = 0x81,
154 
155         // Stream type 0x83 is non-standard,
156         // it could be LPCM or TrueHD AC3
157         STREAMTYPE_LPCM_AC3             = 0x83,
158         STREAMTYPE_EAC3                 = 0x87,
159 
160         //Sample Encrypted types
161         STREAMTYPE_H264_ENCRYPTED       = 0xDB,
162         STREAMTYPE_AAC_ENCRYPTED        = 0xCF,
163         STREAMTYPE_AC3_ENCRYPTED        = 0xC1,
164     };
165 
166     enum {
167         // From ISO/IEC 13818-1: 2007 (E), Table 2-45
168         DESCRIPTOR_CA                   = 0x09,
169 
170         // DVB BlueBook A038 Table 12
171         DESCRIPTOR_DVB_EXTENSION        = 0x7F,
172     };
173 
174     // DVB BlueBook A038 Table 109
175     enum {
176         EXT_DESCRIPTOR_DVB_AC4                  = 0x15,
177         EXT_DESCRIPTOR_DVB_AUDIO_PRESELECTION   = 0x19,
178         EXT_DESCRIPTOR_DVB_RESERVED_MAX         = 0x7F,
179     };
180 
181 protected:
182     virtual ~ATSParser();
183 
184 private:
185     struct Program;
186     struct Stream;
187     struct PSISection;
188     struct CasManager;
189     struct CADescriptor {
CADescriptorATSParser::CADescriptor190         CADescriptor() : mPID(0), mSystemID(-1) {}
191         unsigned mPID;
192         int32_t mSystemID;
193         std::vector<uint8_t> mPrivateData;
194     };
195 
196     struct StreamInfo {
197         unsigned mType;
198         unsigned mTypeExt;
199         unsigned mPID;
200         CADescriptor mCADescriptor;
201         AudioPresentationCollection mAudioPresentations;
202     };
203 
204     sp<CasManager> mCasManager;
205 
206     uint32_t mFlags;
207     Vector<sp<Program> > mPrograms;
208 
209     // Keyed by PID
210     KeyedVector<unsigned, sp<PSISection> > mPSISections;
211 
212     int64_t mAbsoluteTimeAnchorUs;
213 
214     bool mTimeOffsetValid;
215     int64_t mTimeOffsetUs;
216     int64_t mLastRecoveredPTS;
217 
218     size_t mNumTSPacketsParsed;
219 
220     sp<AMessage> mSampleAesKeyItem;
221 
222     void parseProgramAssociationTable(ABitReader *br);
223     void parseProgramMap(ABitReader *br);
224     // Parse PES packet where br is pointing to. If the PES contains a sync
225     // frame, set event with the time and the start offset of this PES.
226     // Note that the method itself does not touch event.
227     void parsePES(ABitReader *br, SyncEvent *event);
228 
229     // Strip remaining packet headers and pass to appropriate program/stream
230     // to parse the payload. If the payload turns out to be PES and contains
231     // a sync frame, event shall be set with the time and start offset of the
232     // PES.
233     // Note that the method itself does not touch event.
234     status_t parsePID(
235         ABitReader *br, unsigned PID,
236         unsigned continuity_counter,
237         unsigned payload_unit_start_indicator,
238         unsigned transport_scrambling_control,
239         unsigned random_access_indicator,
240         SyncEvent *event);
241 
242     status_t parseAdaptationField(
243             ABitReader *br, unsigned PID, unsigned *random_access_indicator);
244 
245     // see feedTSPacket().
246     status_t parseTS(ABitReader *br, SyncEvent *event);
247 
248     void updatePCR(unsigned PID, uint64_t PCR, uint64_t byteOffsetFromStart);
249 
250     uint64_t mPCR[2];
251     uint64_t mPCRBytes[2];
252     int64_t mSystemTimeUs[2];
253     size_t mNumPCRs;
254 
255     DISALLOW_EVIL_CONSTRUCTORS(ATSParser);
256 };
257 
258 }  // namespace android
259 
260 #endif  // A_TS_PARSER_H_
261