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
30namespace android {
31
32class ABitReader;
33struct ABuffer;
34
35struct 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
72        bool isInit() { return mInit; }
73        off64_t getOffset() { return mOffset; }
74        const sp<MediaSource> &getMediaSource() { return mMediaSource; }
75        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
139protected:
140    virtual ~ATSParser();
141
142private:
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