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 <utils/KeyedVector.h>
26 #include <utils/Vector.h>
27 #include <utils/RefBase.h>
28 
29 namespace android {
30 
31 struct ABitReader;
32 struct ABuffer;
33 struct MediaSource;
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     };
50 
51     enum Flags {
52         // The 90kHz clock (PTS/DTS) is absolute, i.e. PTS=0 corresponds to
53         // a media time of 0.
54         // If this flag is _not_ specified, the first PTS encountered in a
55         // program of this stream will be assumed to correspond to media time 0
56         // instead.
57         TS_TIMESTAMPS_ARE_ABSOLUTE = 1,
58         // Video PES packets contain exactly one (aligned) access unit.
59         ALIGNED_VIDEO_DATA         = 2,
60     };
61 
62     ATSParser(uint32_t flags = 0);
63 
64     status_t feedTSPacket(const void *data, size_t size);
65 
66     void signalDiscontinuity(
67             DiscontinuityType type, const sp<AMessage> &extra);
68 
69     void signalEOS(status_t finalResult);
70 
71     enum SourceType {
72         VIDEO = 0,
73         AUDIO = 1,
74         NUM_SOURCE_TYPES = 2
75     };
76     sp<MediaSource> getSource(SourceType type);
77     bool hasSource(SourceType type) const;
78 
79     bool PTSTimeDeltaEstablished();
80 
81     enum {
82         // From ISO/IEC 13818-1: 2000 (E), Table 2-29
83         STREAMTYPE_RESERVED             = 0x00,
84         STREAMTYPE_MPEG1_VIDEO          = 0x01,
85         STREAMTYPE_MPEG2_VIDEO          = 0x02,
86         STREAMTYPE_MPEG1_AUDIO          = 0x03,
87         STREAMTYPE_MPEG2_AUDIO          = 0x04,
88         STREAMTYPE_MPEG2_AUDIO_ADTS     = 0x0f,
89         STREAMTYPE_MPEG4_VIDEO          = 0x10,
90         STREAMTYPE_H264                 = 0x1b,
91 
92         // From ATSC A/53 Part 3:2009, 6.7.1
93         STREAMTYPE_AC3                  = 0x81,
94 
95         // Stream type 0x83 is non-standard,
96         // it could be LPCM or TrueHD AC3
97         STREAMTYPE_LPCM_AC3             = 0x83,
98     };
99 
100 protected:
101     virtual ~ATSParser();
102 
103 private:
104     struct Program;
105     struct Stream;
106     struct PSISection;
107 
108     uint32_t mFlags;
109     Vector<sp<Program> > mPrograms;
110 
111     // Keyed by PID
112     KeyedVector<unsigned, sp<PSISection> > mPSISections;
113 
114     int64_t mAbsoluteTimeAnchorUs;
115 
116     bool mTimeOffsetValid;
117     int64_t mTimeOffsetUs;
118 
119     size_t mNumTSPacketsParsed;
120 
121     void parseProgramAssociationTable(ABitReader *br);
122     void parseProgramMap(ABitReader *br);
123     void parsePES(ABitReader *br);
124 
125     status_t parsePID(
126         ABitReader *br, unsigned PID,
127         unsigned continuity_counter,
128         unsigned payload_unit_start_indicator);
129 
130     void parseAdaptationField(ABitReader *br, unsigned PID);
131     status_t parseTS(ABitReader *br);
132 
133     void updatePCR(unsigned PID, uint64_t PCR, size_t byteOffsetFromStart);
134 
135     uint64_t mPCR[2];
136     size_t mPCRBytes[2];
137     int64_t mSystemTimeUs[2];
138     size_t mNumPCRs;
139 
140     DISALLOW_EVIL_CONSTRUCTORS(ATSParser);
141 };
142 
143 }  // namespace android
144 
145 #endif  // A_TS_PARSER_H_
146