ATSParser.cpp revision bc7f5b2e56107cfeaeeab13cf8979379e3c2f139 
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//#define LOG_NDEBUG 0
18#define LOG_TAG "ATSParser"
19#include <utils/Log.h>
20
21#include "ATSParser.h"
22
23#include "AnotherPacketSource.h"
24#include "ESQueue.h"
25#include "include/avc_utils.h"
26
27#include <media/stagefright/foundation/ABitReader.h>
28#include <media/stagefright/foundation/ABuffer.h>
29#include <media/stagefright/foundation/ADebug.h>
30#include <media/stagefright/foundation/AMessage.h>
31#include <media/stagefright/foundation/hexdump.h>
32#include <media/stagefright/MediaDefs.h>
33#include <media/stagefright/MediaErrors.h>
34#include <media/stagefright/MetaData.h>
35#include <utils/KeyedVector.h>
36
37namespace android {
38
39// I want the expression "y" evaluated even if verbose logging is off.
40#define MY_LOGV(x, y) \
41    do { unsigned tmp = y; LOGV(x, tmp); } while (0)
42
43static const size_t kTSPacketSize = 188;
44
45struct ATSParser::Program : public RefBase {
46    Program(ATSParser *parser, unsigned programMapPID);
47
48    bool parsePID(
49            unsigned pid, unsigned payload_unit_start_indicator,
50            ABitReader *br);
51
52    void signalDiscontinuity(DiscontinuityType type);
53    void signalEOS(status_t finalResult);
54
55    sp<MediaSource> getSource(SourceType type);
56
57    int64_t convertPTSToTimestamp(uint64_t PTS);
58
59    bool PTSTimeDeltaEstablished() const {
60        return mFirstPTSValid;
61    }
62
63private:
64    ATSParser *mParser;
65    unsigned mProgramMapPID;
66    KeyedVector<unsigned, sp<Stream> > mStreams;
67    bool mFirstPTSValid;
68    uint64_t mFirstPTS;
69
70    void parseProgramMap(ABitReader *br);
71
72    DISALLOW_EVIL_CONSTRUCTORS(Program);
73};
74
75struct ATSParser::Stream : public RefBase {
76    Stream(Program *program, unsigned elementaryPID, unsigned streamType);
77
78    unsigned type() const { return mStreamType; }
79    unsigned pid() const { return mElementaryPID; }
80    void setPID(unsigned pid) { mElementaryPID = pid; }
81
82    void parse(
83            unsigned payload_unit_start_indicator,
84            ABitReader *br);
85
86    void signalDiscontinuity(DiscontinuityType type);
87    void signalEOS(status_t finalResult);
88
89    sp<MediaSource> getSource(SourceType type);
90
91protected:
92    virtual ~Stream();
93
94private:
95    Program *mProgram;
96    unsigned mElementaryPID;
97    unsigned mStreamType;
98
99    sp<ABuffer> mBuffer;
100    sp<AnotherPacketSource> mSource;
101    bool mPayloadStarted;
102    DiscontinuityType mPendingDiscontinuity;
103
104    ElementaryStreamQueue mQueue;
105
106    void flush();
107    void parsePES(ABitReader *br);
108
109    void onPayloadData(
110            unsigned PTS_DTS_flags, uint64_t PTS, uint64_t DTS,
111            const uint8_t *data, size_t size);
112
113    void extractAACFrames(const sp<ABuffer> &buffer);
114
115    void deferDiscontinuity(DiscontinuityType type);
116
117    DISALLOW_EVIL_CONSTRUCTORS(Stream);
118};
119
120////////////////////////////////////////////////////////////////////////////////
121
122ATSParser::Program::Program(ATSParser *parser, unsigned programMapPID)
123    : mParser(parser),
124      mProgramMapPID(programMapPID),
125      mFirstPTSValid(false),
126      mFirstPTS(0) {
127}
128
129bool ATSParser::Program::parsePID(
130        unsigned pid, unsigned payload_unit_start_indicator,
131        ABitReader *br) {
132    if (pid == mProgramMapPID) {
133        if (payload_unit_start_indicator) {
134            unsigned skip = br->getBits(8);
135            br->skipBits(skip * 8);
136        }
137
138        parseProgramMap(br);
139        return true;
140    }
141
142    ssize_t index = mStreams.indexOfKey(pid);
143    if (index < 0) {
144        return false;
145    }
146
147    mStreams.editValueAt(index)->parse(
148            payload_unit_start_indicator, br);
149
150    return true;
151}
152
153void ATSParser::Program::signalDiscontinuity(DiscontinuityType type) {
154    for (size_t i = 0; i < mStreams.size(); ++i) {
155        mStreams.editValueAt(i)->signalDiscontinuity(type);
156    }
157}
158
159void ATSParser::Program::signalEOS(status_t finalResult) {
160    for (size_t i = 0; i < mStreams.size(); ++i) {
161        mStreams.editValueAt(i)->signalEOS(finalResult);
162    }
163}
164
165struct StreamInfo {
166    unsigned mType;
167    unsigned mPID;
168};
169
170void ATSParser::Program::parseProgramMap(ABitReader *br) {
171    unsigned table_id = br->getBits(8);
172    LOGV("  table_id = %u", table_id);
173    CHECK_EQ(table_id, 0x02u);
174
175    unsigned section_syntax_indicator = br->getBits(1);
176    LOGV("  section_syntax_indicator = %u", section_syntax_indicator);
177    CHECK_EQ(section_syntax_indicator, 1u);
178
179    CHECK_EQ(br->getBits(1), 0u);
180    MY_LOGV("  reserved = %u", br->getBits(2));
181
182    unsigned section_length = br->getBits(12);
183    LOGV("  section_length = %u", section_length);
184    CHECK_EQ(section_length & 0xc00, 0u);
185    CHECK_LE(section_length, 1021u);
186
187    MY_LOGV("  program_number = %u", br->getBits(16));
188    MY_LOGV("  reserved = %u", br->getBits(2));
189    MY_LOGV("  version_number = %u", br->getBits(5));
190    MY_LOGV("  current_next_indicator = %u", br->getBits(1));
191    MY_LOGV("  section_number = %u", br->getBits(8));
192    MY_LOGV("  last_section_number = %u", br->getBits(8));
193    MY_LOGV("  reserved = %u", br->getBits(3));
194    MY_LOGV("  PCR_PID = 0x%04x", br->getBits(13));
195    MY_LOGV("  reserved = %u", br->getBits(4));
196
197    unsigned program_info_length = br->getBits(12);
198    LOGV("  program_info_length = %u", program_info_length);
199    CHECK_EQ(program_info_length & 0xc00, 0u);
200
201    br->skipBits(program_info_length * 8);  // skip descriptors
202
203    Vector<StreamInfo> infos;
204
205    // infoBytesRemaining is the number of bytes that make up the
206    // variable length section of ES_infos. It does not include the
207    // final CRC.
208    size_t infoBytesRemaining = section_length - 9 - program_info_length - 4;
209
210    while (infoBytesRemaining > 0) {
211        CHECK_GE(infoBytesRemaining, 5u);
212
213        unsigned streamType = br->getBits(8);
214        LOGV("    stream_type = 0x%02x", streamType);
215
216        MY_LOGV("    reserved = %u", br->getBits(3));
217
218        unsigned elementaryPID = br->getBits(13);
219        LOGV("    elementary_PID = 0x%04x", elementaryPID);
220
221        MY_LOGV("    reserved = %u", br->getBits(4));
222
223        unsigned ES_info_length = br->getBits(12);
224        LOGV("    ES_info_length = %u", ES_info_length);
225        CHECK_EQ(ES_info_length & 0xc00, 0u);
226
227        CHECK_GE(infoBytesRemaining - 5, ES_info_length);
228
229#if 0
230        br->skipBits(ES_info_length * 8);  // skip descriptors
231#else
232        unsigned info_bytes_remaining = ES_info_length;
233        while (info_bytes_remaining >= 2) {
234            MY_LOGV("      tag = 0x%02x", br->getBits(8));
235
236            unsigned descLength = br->getBits(8);
237            LOGV("      len = %u", descLength);
238
239            CHECK_GE(info_bytes_remaining, 2 + descLength);
240
241            br->skipBits(descLength * 8);
242
243            info_bytes_remaining -= descLength + 2;
244        }
245        CHECK_EQ(info_bytes_remaining, 0u);
246#endif
247
248        StreamInfo info;
249        info.mType = streamType;
250        info.mPID = elementaryPID;
251        infos.push(info);
252
253        infoBytesRemaining -= 5 + ES_info_length;
254    }
255
256    CHECK_EQ(infoBytesRemaining, 0u);
257    MY_LOGV("  CRC = 0x%08x", br->getBits(32));
258
259    bool PIDsChanged = false;
260    for (size_t i = 0; i < infos.size(); ++i) {
261        StreamInfo &info = infos.editItemAt(i);
262
263        ssize_t index = mStreams.indexOfKey(info.mPID);
264
265        if (index >= 0 && mStreams.editValueAt(index)->type() != info.mType) {
266            LOGI("uh oh. stream PIDs have changed.");
267            PIDsChanged = true;
268            break;
269        }
270    }
271
272    if (PIDsChanged) {
273        mStreams.clear();
274    }
275
276    for (size_t i = 0; i < infos.size(); ++i) {
277        StreamInfo &info = infos.editItemAt(i);
278
279        ssize_t index = mStreams.indexOfKey(info.mPID);
280
281        if (index < 0) {
282            sp<Stream> stream = new Stream(this, info.mPID, info.mType);
283            mStreams.add(info.mPID, stream);
284
285            if (PIDsChanged) {
286                stream->signalDiscontinuity(DISCONTINUITY_FORMATCHANGE);
287            }
288        }
289    }
290}
291
292sp<MediaSource> ATSParser::Program::getSource(SourceType type) {
293    size_t index = (type == MPEG2ADTS_AUDIO) ? 0 : 0;
294
295    for (size_t i = 0; i < mStreams.size(); ++i) {
296        sp<MediaSource> source = mStreams.editValueAt(i)->getSource(type);
297        if (source != NULL) {
298            if (index == 0) {
299                return source;
300            }
301            --index;
302        }
303    }
304
305    return NULL;
306}
307
308int64_t ATSParser::Program::convertPTSToTimestamp(uint64_t PTS) {
309    if (!mFirstPTSValid) {
310        mFirstPTSValid = true;
311        mFirstPTS = PTS;
312        PTS = 0;
313    } else if (PTS < mFirstPTS) {
314        PTS = 0;
315    } else {
316        PTS -= mFirstPTS;
317    }
318
319    return (PTS * 100) / 9;
320}
321
322////////////////////////////////////////////////////////////////////////////////
323
324ATSParser::Stream::Stream(
325        Program *program, unsigned elementaryPID, unsigned streamType)
326    : mProgram(program),
327      mElementaryPID(elementaryPID),
328      mStreamType(streamType),
329      mBuffer(new ABuffer(192 * 1024)),
330      mPayloadStarted(false),
331      mPendingDiscontinuity(DISCONTINUITY_NONE),
332      mQueue(streamType == 0x1b
333              ? ElementaryStreamQueue::H264 : ElementaryStreamQueue::AAC) {
334    mBuffer->setRange(0, 0);
335
336    LOGV("new stream PID 0x%02x, type 0x%02x", elementaryPID, streamType);
337}
338
339ATSParser::Stream::~Stream() {
340}
341
342void ATSParser::Stream::parse(
343        unsigned payload_unit_start_indicator, ABitReader *br) {
344    if (payload_unit_start_indicator) {
345        if (mPayloadStarted) {
346            // Otherwise we run the danger of receiving the trailing bytes
347            // of a PES packet that we never saw the start of and assuming
348            // we have a a complete PES packet.
349
350            flush();
351        }
352
353        mPayloadStarted = true;
354    }
355
356    if (!mPayloadStarted) {
357        return;
358    }
359
360    size_t payloadSizeBits = br->numBitsLeft();
361    CHECK_EQ(payloadSizeBits % 8, 0u);
362
363    CHECK_LE(mBuffer->size() + payloadSizeBits / 8, mBuffer->capacity());
364
365    memcpy(mBuffer->data() + mBuffer->size(), br->data(), payloadSizeBits / 8);
366    mBuffer->setRange(0, mBuffer->size() + payloadSizeBits / 8);
367}
368
369void ATSParser::Stream::signalDiscontinuity(DiscontinuityType type) {
370    mPayloadStarted = false;
371    mBuffer->setRange(0, 0);
372
373    switch (type) {
374        case DISCONTINUITY_HTTPLIVE:
375        {
376            mQueue.clear(true);
377
378            if (mStreamType == 0x1b) {
379                // Don't signal discontinuities on audio streams.
380                if (mSource != NULL) {
381                    mSource->queueDiscontinuity(type);
382                } else {
383                    deferDiscontinuity(type);
384                }
385            }
386            break;
387        }
388
389        case DISCONTINUITY_SEEK:
390        case DISCONTINUITY_FORMATCHANGE:
391        {
392            bool isASeek = (type == DISCONTINUITY_SEEK);
393
394            mQueue.clear(!isASeek);
395
396            if (mSource != NULL) {
397                mSource->queueDiscontinuity(type);
398            } else {
399                deferDiscontinuity(type);
400            }
401            break;
402        }
403
404        default:
405            TRESPASS();
406            break;
407    }
408}
409
410void ATSParser::Stream::deferDiscontinuity(DiscontinuityType type) {
411    if (type > mPendingDiscontinuity) {
412        // Only upgrade discontinuities.
413        mPendingDiscontinuity = type;
414    }
415}
416
417void ATSParser::Stream::signalEOS(status_t finalResult) {
418    if (mSource != NULL) {
419        mSource->signalEOS(finalResult);
420    }
421}
422
423void ATSParser::Stream::parsePES(ABitReader *br) {
424    unsigned packet_startcode_prefix = br->getBits(24);
425
426    LOGV("packet_startcode_prefix = 0x%08x", packet_startcode_prefix);
427
428    CHECK_EQ(packet_startcode_prefix, 0x000001u);
429
430    unsigned stream_id = br->getBits(8);
431    LOGV("stream_id = 0x%02x", stream_id);
432
433    unsigned PES_packet_length = br->getBits(16);
434    LOGV("PES_packet_length = %u", PES_packet_length);
435
436    if (stream_id != 0xbc  // program_stream_map
437            && stream_id != 0xbe  // padding_stream
438            && stream_id != 0xbf  // private_stream_2
439            && stream_id != 0xf0  // ECM
440            && stream_id != 0xf1  // EMM
441            && stream_id != 0xff  // program_stream_directory
442            && stream_id != 0xf2  // DSMCC
443            && stream_id != 0xf8) {  // H.222.1 type E
444        CHECK_EQ(br->getBits(2), 2u);
445
446        MY_LOGV("PES_scrambling_control = %u", br->getBits(2));
447        MY_LOGV("PES_priority = %u", br->getBits(1));
448        MY_LOGV("data_alignment_indicator = %u", br->getBits(1));
449        MY_LOGV("copyright = %u", br->getBits(1));
450        MY_LOGV("original_or_copy = %u", br->getBits(1));
451
452        unsigned PTS_DTS_flags = br->getBits(2);
453        LOGV("PTS_DTS_flags = %u", PTS_DTS_flags);
454
455        unsigned ESCR_flag = br->getBits(1);
456        LOGV("ESCR_flag = %u", ESCR_flag);
457
458        unsigned ES_rate_flag = br->getBits(1);
459        LOGV("ES_rate_flag = %u", ES_rate_flag);
460
461        unsigned DSM_trick_mode_flag = br->getBits(1);
462        LOGV("DSM_trick_mode_flag = %u", DSM_trick_mode_flag);
463
464        unsigned additional_copy_info_flag = br->getBits(1);
465        LOGV("additional_copy_info_flag = %u", additional_copy_info_flag);
466
467        MY_LOGV("PES_CRC_flag = %u", br->getBits(1));
468        MY_LOGV("PES_extension_flag = %u", br->getBits(1));
469
470        unsigned PES_header_data_length = br->getBits(8);
471        LOGV("PES_header_data_length = %u", PES_header_data_length);
472
473        unsigned optional_bytes_remaining = PES_header_data_length;
474
475        uint64_t PTS = 0, DTS = 0;
476
477        if (PTS_DTS_flags == 2 || PTS_DTS_flags == 3) {
478            CHECK_GE(optional_bytes_remaining, 5u);
479
480            CHECK_EQ(br->getBits(4), PTS_DTS_flags);
481
482            PTS = ((uint64_t)br->getBits(3)) << 30;
483            CHECK_EQ(br->getBits(1), 1u);
484            PTS |= ((uint64_t)br->getBits(15)) << 15;
485            CHECK_EQ(br->getBits(1), 1u);
486            PTS |= br->getBits(15);
487            CHECK_EQ(br->getBits(1), 1u);
488
489            LOGV("PTS = %llu", PTS);
490            // LOGI("PTS = %.2f secs", PTS / 90000.0f);
491
492            optional_bytes_remaining -= 5;
493
494            if (PTS_DTS_flags == 3) {
495                CHECK_GE(optional_bytes_remaining, 5u);
496
497                CHECK_EQ(br->getBits(4), 1u);
498
499                DTS = ((uint64_t)br->getBits(3)) << 30;
500                CHECK_EQ(br->getBits(1), 1u);
501                DTS |= ((uint64_t)br->getBits(15)) << 15;
502                CHECK_EQ(br->getBits(1), 1u);
503                DTS |= br->getBits(15);
504                CHECK_EQ(br->getBits(1), 1u);
505
506                LOGV("DTS = %llu", DTS);
507
508                optional_bytes_remaining -= 5;
509            }
510        }
511
512        if (ESCR_flag) {
513            CHECK_GE(optional_bytes_remaining, 6u);
514
515            br->getBits(2);
516
517            uint64_t ESCR = ((uint64_t)br->getBits(3)) << 30;
518            CHECK_EQ(br->getBits(1), 1u);
519            ESCR |= ((uint64_t)br->getBits(15)) << 15;
520            CHECK_EQ(br->getBits(1), 1u);
521            ESCR |= br->getBits(15);
522            CHECK_EQ(br->getBits(1), 1u);
523
524            LOGV("ESCR = %llu", ESCR);
525            MY_LOGV("ESCR_extension = %u", br->getBits(9));
526
527            CHECK_EQ(br->getBits(1), 1u);
528
529            optional_bytes_remaining -= 6;
530        }
531
532        if (ES_rate_flag) {
533            CHECK_GE(optional_bytes_remaining, 3u);
534
535            CHECK_EQ(br->getBits(1), 1u);
536            MY_LOGV("ES_rate = %u", br->getBits(22));
537            CHECK_EQ(br->getBits(1), 1u);
538
539            optional_bytes_remaining -= 3;
540        }
541
542        br->skipBits(optional_bytes_remaining * 8);
543
544        // ES data follows.
545
546        if (PES_packet_length != 0) {
547            CHECK_GE(PES_packet_length, PES_header_data_length + 3);
548
549            unsigned dataLength =
550                PES_packet_length - 3 - PES_header_data_length;
551
552            CHECK_GE(br->numBitsLeft(), dataLength * 8);
553
554            onPayloadData(
555                    PTS_DTS_flags, PTS, DTS, br->data(), dataLength);
556
557            br->skipBits(dataLength * 8);
558        } else {
559            onPayloadData(
560                    PTS_DTS_flags, PTS, DTS,
561                    br->data(), br->numBitsLeft() / 8);
562
563            size_t payloadSizeBits = br->numBitsLeft();
564            CHECK_EQ(payloadSizeBits % 8, 0u);
565
566            LOGV("There's %d bytes of payload.", payloadSizeBits / 8);
567        }
568    } else if (stream_id == 0xbe) {  // padding_stream
569        CHECK_NE(PES_packet_length, 0u);
570        br->skipBits(PES_packet_length * 8);
571    } else {
572        CHECK_NE(PES_packet_length, 0u);
573        br->skipBits(PES_packet_length * 8);
574    }
575}
576
577void ATSParser::Stream::flush() {
578    if (mBuffer->size() == 0) {
579        return;
580    }
581
582    LOGV("flushing stream 0x%04x size = %d", mElementaryPID, mBuffer->size());
583
584    ABitReader br(mBuffer->data(), mBuffer->size());
585    parsePES(&br);
586
587    mBuffer->setRange(0, 0);
588}
589
590void ATSParser::Stream::onPayloadData(
591        unsigned PTS_DTS_flags, uint64_t PTS, uint64_t DTS,
592        const uint8_t *data, size_t size) {
593    LOGV("onPayloadData mStreamType=0x%02x", mStreamType);
594
595    CHECK(PTS_DTS_flags == 2 || PTS_DTS_flags == 3);
596    int64_t timeUs = mProgram->convertPTSToTimestamp(PTS);
597
598    status_t err = mQueue.appendData(data, size, timeUs);
599
600    if (err != OK) {
601        return;
602    }
603
604    sp<ABuffer> accessUnit;
605    while ((accessUnit = mQueue.dequeueAccessUnit()) != NULL) {
606        if (mSource == NULL) {
607            sp<MetaData> meta = mQueue.getFormat();
608
609            if (meta != NULL) {
610                LOGV("created source!");
611                mSource = new AnotherPacketSource(meta);
612
613                if (mPendingDiscontinuity != DISCONTINUITY_NONE) {
614                    mSource->queueDiscontinuity(mPendingDiscontinuity);
615                    mPendingDiscontinuity = DISCONTINUITY_NONE;
616                }
617
618                mSource->queueAccessUnit(accessUnit);
619            }
620        } else if (mQueue.getFormat() != NULL) {
621            // After a discontinuity we invalidate the queue's format
622            // and won't enqueue any access units to the source until
623            // the queue has reestablished the new format.
624
625            if (mSource->getFormat() == NULL) {
626                mSource->setFormat(mQueue.getFormat());
627            }
628            mSource->queueAccessUnit(accessUnit);
629        }
630    }
631}
632
633sp<MediaSource> ATSParser::Stream::getSource(SourceType type) {
634    if ((type == AVC_VIDEO && mStreamType == 0x1b)
635        || (type == MPEG2ADTS_AUDIO && mStreamType == 0x0f)) {
636        return mSource;
637    }
638
639    return NULL;
640}
641
642////////////////////////////////////////////////////////////////////////////////
643
644ATSParser::ATSParser() {
645}
646
647ATSParser::~ATSParser() {
648}
649
650void ATSParser::feedTSPacket(const void *data, size_t size) {
651    CHECK_EQ(size, kTSPacketSize);
652
653    ABitReader br((const uint8_t *)data, kTSPacketSize);
654    parseTS(&br);
655}
656
657void ATSParser::signalDiscontinuity(DiscontinuityType type) {
658    for (size_t i = 0; i < mPrograms.size(); ++i) {
659        mPrograms.editItemAt(i)->signalDiscontinuity(type);
660    }
661}
662
663void ATSParser::signalEOS(status_t finalResult) {
664    CHECK_NE(finalResult, (status_t)OK);
665
666    for (size_t i = 0; i < mPrograms.size(); ++i) {
667        mPrograms.editItemAt(i)->signalEOS(finalResult);
668    }
669}
670
671void ATSParser::parseProgramAssociationTable(ABitReader *br) {
672    unsigned table_id = br->getBits(8);
673    LOGV("  table_id = %u", table_id);
674    CHECK_EQ(table_id, 0x00u);
675
676    unsigned section_syntax_indictor = br->getBits(1);
677    LOGV("  section_syntax_indictor = %u", section_syntax_indictor);
678    CHECK_EQ(section_syntax_indictor, 1u);
679
680    CHECK_EQ(br->getBits(1), 0u);
681    MY_LOGV("  reserved = %u", br->getBits(2));
682
683    unsigned section_length = br->getBits(12);
684    LOGV("  section_length = %u", section_length);
685    CHECK_EQ(section_length & 0xc00, 0u);
686
687    MY_LOGV("  transport_stream_id = %u", br->getBits(16));
688    MY_LOGV("  reserved = %u", br->getBits(2));
689    MY_LOGV("  version_number = %u", br->getBits(5));
690    MY_LOGV("  current_next_indicator = %u", br->getBits(1));
691    MY_LOGV("  section_number = %u", br->getBits(8));
692    MY_LOGV("  last_section_number = %u", br->getBits(8));
693
694    size_t numProgramBytes = (section_length - 5 /* header */ - 4 /* crc */);
695    CHECK_EQ((numProgramBytes % 4), 0u);
696
697    for (size_t i = 0; i < numProgramBytes / 4; ++i) {
698        unsigned program_number = br->getBits(16);
699        LOGV("    program_number = %u", program_number);
700
701        MY_LOGV("    reserved = %u", br->getBits(3));
702
703        if (program_number == 0) {
704            MY_LOGV("    network_PID = 0x%04x", br->getBits(13));
705        } else {
706            unsigned programMapPID = br->getBits(13);
707
708            LOGV("    program_map_PID = 0x%04x", programMapPID);
709
710            mPrograms.push(new Program(this, programMapPID));
711        }
712    }
713
714    MY_LOGV("  CRC = 0x%08x", br->getBits(32));
715}
716
717void ATSParser::parsePID(
718        ABitReader *br, unsigned PID,
719        unsigned payload_unit_start_indicator) {
720    if (PID == 0) {
721        if (payload_unit_start_indicator) {
722            unsigned skip = br->getBits(8);
723            br->skipBits(skip * 8);
724        }
725        parseProgramAssociationTable(br);
726        return;
727    }
728
729    bool handled = false;
730    for (size_t i = 0; i < mPrograms.size(); ++i) {
731        if (mPrograms.editItemAt(i)->parsePID(
732                    PID, payload_unit_start_indicator, br)) {
733            handled = true;
734            break;
735        }
736    }
737
738    if (!handled) {
739        LOGV("PID 0x%04x not handled.", PID);
740    }
741}
742
743void ATSParser::parseAdaptationField(ABitReader *br) {
744    unsigned adaptation_field_length = br->getBits(8);
745    if (adaptation_field_length > 0) {
746        br->skipBits(adaptation_field_length * 8);  // XXX
747    }
748}
749
750void ATSParser::parseTS(ABitReader *br) {
751    LOGV("---");
752
753    unsigned sync_byte = br->getBits(8);
754    CHECK_EQ(sync_byte, 0x47u);
755
756    MY_LOGV("transport_error_indicator = %u", br->getBits(1));
757
758    unsigned payload_unit_start_indicator = br->getBits(1);
759    LOGV("payload_unit_start_indicator = %u", payload_unit_start_indicator);
760
761    MY_LOGV("transport_priority = %u", br->getBits(1));
762
763    unsigned PID = br->getBits(13);
764    LOGV("PID = 0x%04x", PID);
765
766    MY_LOGV("transport_scrambling_control = %u", br->getBits(2));
767
768    unsigned adaptation_field_control = br->getBits(2);
769    LOGV("adaptation_field_control = %u", adaptation_field_control);
770
771    unsigned continuity_counter = br->getBits(4);
772    LOGV("continuity_counter = %u", continuity_counter);
773
774    // LOGI("PID = 0x%04x, continuity_counter = %u", PID, continuity_counter);
775
776    if (adaptation_field_control == 2 || adaptation_field_control == 3) {
777        parseAdaptationField(br);
778    }
779
780    if (adaptation_field_control == 1 || adaptation_field_control == 3) {
781        parsePID(br, PID, payload_unit_start_indicator);
782    }
783}
784
785sp<MediaSource> ATSParser::getSource(SourceType type) {
786    for (size_t i = 0; i < mPrograms.size(); ++i) {
787        sp<MediaSource> source = mPrograms.editItemAt(i)->getSource(type);
788
789        if (source != NULL) {
790            return source;
791        }
792    }
793
794    return NULL;
795}
796
797bool ATSParser::PTSTimeDeltaEstablished() {
798    if (mPrograms.isEmpty()) {
799        return false;
800    }
801
802    return mPrograms.editItemAt(0)->PTSTimeDeltaEstablished();
803}
804
805}  // namespace android
806