media/formats/mp4/box_definitions.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "media/formats/mp4/box_definitions.h"
   6
   7 #include "base/logging.h"
   8 #include "media/formats/mp4/es_descriptor.h"
   9 #include "media/formats/mp4/rcheck.h"
  10
  11 namespace media {
  12 namespace mp4 {
  13
  14 FileType::FileType() {}
  15 FileType::~FileType() {}
  16 FourCC FileType::BoxType() const { return FOURCC_FTYP; }
  17
  18 bool FileType::Parse(BoxReader* reader) {
  19   RCHECK(reader->ReadFourCC(&major_brand) && reader->Read4(&minor_version));
  20   size_t num_brands = (reader->size() - reader->pos()) / sizeof(FourCC);
  21   return reader->SkipBytes(sizeof(FourCC) * num_brands);  // compatible_brands
  22 }
  23
  24 ProtectionSystemSpecificHeader::ProtectionSystemSpecificHeader() {}
  25 ProtectionSystemSpecificHeader::~ProtectionSystemSpecificHeader() {}
  26 FourCC ProtectionSystemSpecificHeader::BoxType() const { return FOURCC_PSSH; }
  27
  28 bool ProtectionSystemSpecificHeader::Parse(BoxReader* reader) {
  29   // Validate the box's contents and hang on to the system ID.
  30   uint32 size;
  31   RCHECK(reader->ReadFullBoxHeader() &&
  32          reader->ReadVec(&system_id, 16) &&
  33          reader->Read4(&size) &&
  34          reader->HasBytes(size));
  35
  36   // Copy the entire box, including the header, for passing to EME as initData.
  37   DCHECK(raw_box.empty());
  38   raw_box.assign(reader->data(), reader->data() + reader->size());
  39   return true;
  40 }
  41
  42 SampleAuxiliaryInformationOffset::SampleAuxiliaryInformationOffset() {}
  43 SampleAuxiliaryInformationOffset::~SampleAuxiliaryInformationOffset() {}
  44 FourCC SampleAuxiliaryInformationOffset::BoxType() const { return FOURCC_SAIO; }
  45
  46 bool SampleAuxiliaryInformationOffset::Parse(BoxReader* reader) {
  47   RCHECK(reader->ReadFullBoxHeader());
  48   if (reader->flags() & 1)
  49     RCHECK(reader->SkipBytes(8));
  50
  51   uint32 count;
  52   RCHECK(reader->Read4(&count) &&
  53          reader->HasBytes(count * (reader->version() == 1 ? 8 : 4)));
  54   offsets.resize(count);
  55
  56   for (uint32 i = 0; i < count; i++) {
  57     if (reader->version() == 1) {
  58       RCHECK(reader->Read8(&offsets[i]));
  59     } else {
  60       RCHECK(reader->Read4Into8(&offsets[i]));
  61     }
  62   }
  63   return true;
  64 }
  65
  66 SampleAuxiliaryInformationSize::SampleAuxiliaryInformationSize()
  67   : default_sample_info_size(0), sample_count(0) {
  68 }
  69 SampleAuxiliaryInformationSize::~SampleAuxiliaryInformationSize() {}
  70 FourCC SampleAuxiliaryInformationSize::BoxType() const { return FOURCC_SAIZ; }
  71
  72 bool SampleAuxiliaryInformationSize::Parse(BoxReader* reader) {
  73   RCHECK(reader->ReadFullBoxHeader());
  74   if (reader->flags() & 1)
  75     RCHECK(reader->SkipBytes(8));
  76
  77   RCHECK(reader->Read1(&default_sample_info_size) &&
  78          reader->Read4(&sample_count));
  79   if (default_sample_info_size == 0)
  80     return reader->ReadVec(&sample_info_sizes, sample_count);
  81   return true;
  82 }
  83
  84 OriginalFormat::OriginalFormat() : format(FOURCC_NULL) {}
  85 OriginalFormat::~OriginalFormat() {}
  86 FourCC OriginalFormat::BoxType() const { return FOURCC_FRMA; }
  87
  88 bool OriginalFormat::Parse(BoxReader* reader) {
  89   return reader->ReadFourCC(&format);
  90 }
  91
  92 SchemeType::SchemeType() : type(FOURCC_NULL), version(0) {}
  93 SchemeType::~SchemeType() {}
  94 FourCC SchemeType::BoxType() const { return FOURCC_SCHM; }
  95
  96 bool SchemeType::Parse(BoxReader* reader) {
  97   RCHECK(reader->ReadFullBoxHeader() &&
  98          reader->ReadFourCC(&type) &&
  99          reader->Read4(&version));
 100   return true;
 101 }
 102
 103 TrackEncryption::TrackEncryption()
 104   : is_encrypted(false), default_iv_size(0) {
 105 }
 106 TrackEncryption::~TrackEncryption() {}
 107 FourCC TrackEncryption::BoxType() const { return FOURCC_TENC; }
 108
 109 bool TrackEncryption::Parse(BoxReader* reader) {
 110   uint8 flag;
 111   RCHECK(reader->ReadFullBoxHeader() &&
 112          reader->SkipBytes(2) &&
 113          reader->Read1(&flag) &&
 114          reader->Read1(&default_iv_size) &&
 115          reader->ReadVec(&default_kid, 16));
 116   is_encrypted = (flag != 0);
 117   if (is_encrypted) {
 118     RCHECK(default_iv_size == 8 || default_iv_size == 16);
 119   } else {
 120     RCHECK(default_iv_size == 0);
 121   }
 122   return true;
 123 }
 124
 125 SchemeInfo::SchemeInfo() {}
 126 SchemeInfo::~SchemeInfo() {}
 127 FourCC SchemeInfo::BoxType() const { return FOURCC_SCHI; }
 128
 129 bool SchemeInfo::Parse(BoxReader* reader) {
 130   return reader->ScanChildren() && reader->ReadChild(&track_encryption);
 131 }
 132
 133 ProtectionSchemeInfo::ProtectionSchemeInfo() {}
 134 ProtectionSchemeInfo::~ProtectionSchemeInfo() {}
 135 FourCC ProtectionSchemeInfo::BoxType() const { return FOURCC_SINF; }
 136
 137 bool ProtectionSchemeInfo::Parse(BoxReader* reader) {
 138   RCHECK(reader->ScanChildren() &&
 139          reader->ReadChild(&format) &&
 140          reader->ReadChild(&type));
 141   if (type.type == FOURCC_CENC)
 142     RCHECK(reader->ReadChild(&info));
 143   // Other protection schemes are silently ignored. Since the protection scheme
 144   // type can't be determined until this box is opened, we return 'true' for
 145   // non-CENC protection scheme types. It is the parent box's responsibility to
 146   // ensure that this scheme type is a supported one.
 147   return true;
 148 }
 149
 150 MovieHeader::MovieHeader()
 151     : creation_time(0),
 152       modification_time(0),
 153       timescale(0),
 154       duration(0),
 155       rate(-1),
 156       volume(-1),
 157       next_track_id(0) {}
 158 MovieHeader::~MovieHeader() {}
 159 FourCC MovieHeader::BoxType() const { return FOURCC_MVHD; }
 160
 161 bool MovieHeader::Parse(BoxReader* reader) {
 162   RCHECK(reader->ReadFullBoxHeader());
 163
 164   if (reader->version() == 1) {
 165     RCHECK(reader->Read8(&creation_time) &&
 166            reader->Read8(&modification_time) &&
 167            reader->Read4(&timescale) &&
 168            reader->Read8(&duration));
 169   } else {
 170     RCHECK(reader->Read4Into8(&creation_time) &&
 171            reader->Read4Into8(&modification_time) &&
 172            reader->Read4(&timescale) &&
 173            reader->Read4Into8(&duration));
 174   }
 175
 176   RCHECK(reader->Read4s(&rate) &&
 177          reader->Read2s(&volume) &&
 178          reader->SkipBytes(10) &&  // reserved
 179          reader->SkipBytes(36) &&  // matrix
 180          reader->SkipBytes(24) &&  // predefined zero
 181          reader->Read4(&next_track_id));
 182   return true;
 183 }
 184
 185 TrackHeader::TrackHeader()
 186     : creation_time(0),
 187       modification_time(0),
 188       track_id(0),
 189       duration(0),
 190       layer(-1),
 191       alternate_group(-1),
 192       volume(-1),
 193       width(0),
 194       height(0) {}
 195 TrackHeader::~TrackHeader() {}
 196 FourCC TrackHeader::BoxType() const { return FOURCC_TKHD; }
 197
 198 bool TrackHeader::Parse(BoxReader* reader) {
 199   RCHECK(reader->ReadFullBoxHeader());
 200   if (reader->version() == 1) {
 201     RCHECK(reader->Read8(&creation_time) &&
 202            reader->Read8(&modification_time) &&
 203            reader->Read4(&track_id) &&
 204            reader->SkipBytes(4) &&    // reserved
 205            reader->Read8(&duration));
 206   } else {
 207     RCHECK(reader->Read4Into8(&creation_time) &&
 208            reader->Read4Into8(&modification_time) &&
 209            reader->Read4(&track_id) &&
 210            reader->SkipBytes(4) &&   // reserved
 211            reader->Read4Into8(&duration));
 212   }
 213
 214   RCHECK(reader->SkipBytes(8) &&  // reserved
 215          reader->Read2s(&layer) &&
 216          reader->Read2s(&alternate_group) &&
 217          reader->Read2s(&volume) &&
 218          reader->SkipBytes(2) &&  // reserved
 219          reader->SkipBytes(36) &&  // matrix
 220          reader->Read4(&width) &&
 221          reader->Read4(&height));
 222   width >>= 16;
 223   height >>= 16;
 224   return true;
 225 }
 226
 227 SampleDescription::SampleDescription() : type(kInvalid) {}
 228 SampleDescription::~SampleDescription() {}
 229 FourCC SampleDescription::BoxType() const { return FOURCC_STSD; }
 230
 231 bool SampleDescription::Parse(BoxReader* reader) {
 232   uint32 count;
 233   RCHECK(reader->SkipBytes(4) &&
 234          reader->Read4(&count));
 235   video_entries.clear();
 236   audio_entries.clear();
 237
 238   // Note: this value is preset before scanning begins. See comments in the
 239   // Parse(Media*) function.
 240   if (type == kVideo) {
 241     RCHECK(reader->ReadAllChildren(&video_entries));
 242   } else if (type == kAudio) {
 243     RCHECK(reader->ReadAllChildren(&audio_entries));
 244   }
 245   return true;
 246 }
 247
 248 SyncSample::SyncSample() : is_present(false) {}
 249 SyncSample::~SyncSample() {}
 250 FourCC SyncSample::BoxType() const { return FOURCC_STSS; }
 251
 252 bool SyncSample::Parse(BoxReader* reader) {
 253   uint32 entry_count;
 254   RCHECK(reader->ReadFullBoxHeader() &&
 255          reader->Read4(&entry_count));
 256
 257   is_present = true;
 258
 259   entries.resize(entry_count);
 260
 261   if (entry_count == 0)
 262     return true;
 263
 264   for (size_t i = 0; i < entry_count; ++i)
 265     RCHECK(reader->Read4(&entries[i]));
 266
 267   return true;
 268 }
 269
 270 bool SyncSample::IsSyncSample(size_t k) const {
 271   // ISO/IEC 14496-12 Section 8.6.2.1 : If the sync sample box is not present,
 272   // every sample is a sync sample.
 273   if (!is_present)
 274     return true;
 275
 276   // ISO/IEC 14496-12  Section 8.6.2.3 : If entry_count is zero, there are no
 277   // sync samples within the stream.
 278   if (entries.size() == 0u)
 279     return false;
 280
 281   for (size_t i = 0; i < entries.size(); ++i) {
 282     if (entries[i] == k)
 283       return true;
 284   }
 285
 286   return false;
 287 }
 288
 289 SampleTable::SampleTable() {}
 290 SampleTable::~SampleTable() {}
 291 FourCC SampleTable::BoxType() const { return FOURCC_STBL; }
 292
 293 bool SampleTable::Parse(BoxReader* reader) {
 294   return reader->ScanChildren() &&
 295       reader->ReadChild(&description) &&
 296       reader->MaybeReadChild(&sync_sample);
 297 }
 298
 299 EditList::EditList() {}
 300 EditList::~EditList() {}
 301 FourCC EditList::BoxType() const { return FOURCC_ELST; }
 302
 303 bool EditList::Parse(BoxReader* reader) {
 304   uint32 count;
 305   RCHECK(reader->ReadFullBoxHeader() && reader->Read4(&count));
 306
 307   if (reader->version() == 1) {
 308     RCHECK(reader->HasBytes(count * 20));
 309   } else {
 310     RCHECK(reader->HasBytes(count * 12));
 311   }
 312   edits.resize(count);
 313
 314   for (std::vector<EditListEntry>::iterator edit = edits.begin();
 315        edit != edits.end(); ++edit) {
 316     if (reader->version() == 1) {
 317       RCHECK(reader->Read8(&edit->segment_duration) &&
 318              reader->Read8s(&edit->media_time));
 319     } else {
 320       RCHECK(reader->Read4Into8(&edit->segment_duration) &&
 321              reader->Read4sInto8s(&edit->media_time));
 322     }
 323     RCHECK(reader->Read2s(&edit->media_rate_integer) &&
 324            reader->Read2s(&edit->media_rate_fraction));
 325   }
 326   return true;
 327 }
 328
 329 Edit::Edit() {}
 330 Edit::~Edit() {}
 331 FourCC Edit::BoxType() const { return FOURCC_EDTS; }
 332
 333 bool Edit::Parse(BoxReader* reader) {
 334   return reader->ScanChildren() && reader->ReadChild(&list);
 335 }
 336
 337 HandlerReference::HandlerReference() : type(kInvalid) {}
 338 HandlerReference::~HandlerReference() {}
 339 FourCC HandlerReference::BoxType() const { return FOURCC_HDLR; }
 340
 341 bool HandlerReference::Parse(BoxReader* reader) {
 342   FourCC hdlr_type;
 343   RCHECK(reader->SkipBytes(8) && reader->ReadFourCC(&hdlr_type));
 344   // Note: remaining fields in box ignored
 345   if (hdlr_type == FOURCC_VIDE) {
 346     type = kVideo;
 347   } else if (hdlr_type == FOURCC_SOUN) {
 348     type = kAudio;
 349   } else {
 350     type = kInvalid;
 351   }
 352   return true;
 353 }
 354
 355 AVCDecoderConfigurationRecord::AVCDecoderConfigurationRecord()
 356     : version(0),
 357       profile_indication(0),
 358       profile_compatibility(0),
 359       avc_level(0),
 360       length_size(0) {}
 361
 362 AVCDecoderConfigurationRecord::~AVCDecoderConfigurationRecord() {}
 363 FourCC AVCDecoderConfigurationRecord::BoxType() const { return FOURCC_AVCC; }
 364
 365 bool AVCDecoderConfigurationRecord::Parse(BoxReader* reader) {
 366   return ParseInternal(reader, reader->log_cb());
 367 }
 368
 369 bool AVCDecoderConfigurationRecord::Parse(const uint8* data, int data_size) {
 370   BufferReader reader(data, data_size);
 371   return ParseInternal(&reader, LogCB());
 372 }
 373
 374 bool AVCDecoderConfigurationRecord::ParseInternal(BufferReader* reader,
 375                                                   const LogCB& log_cb) {
 376   RCHECK(reader->Read1(&version) && version == 1 &&
 377          reader->Read1(&profile_indication) &&
 378          reader->Read1(&profile_compatibility) &&
 379          reader->Read1(&avc_level));
 380
 381   uint8 length_size_minus_one;
 382   RCHECK(reader->Read1(&length_size_minus_one));
 383   length_size = (length_size_minus_one & 0x3) + 1;
 384
 385   RCHECK(length_size != 3); // Only values of 1, 2, and 4 are valid.
 386
 387   uint8 num_sps;
 388   RCHECK(reader->Read1(&num_sps));
 389   num_sps &= 0x1f;
 390
 391   sps_list.resize(num_sps);
 392   for (int i = 0; i < num_sps; i++) {
 393     uint16 sps_length;
 394     RCHECK(reader->Read2(&sps_length) &&
 395            reader->ReadVec(&sps_list[i], sps_length));
 396     RCHECK(sps_list[i].size() > 4);
 397
 398     if (!log_cb.is_null()) {
 399       MEDIA_LOG(log_cb) << "Video codec: avc1." << std::hex
 400                         << static_cast<int>(sps_list[i][1])
 401                         << static_cast<int>(sps_list[i][2])
 402                         << static_cast<int>(sps_list[i][3]);
 403     }
 404   }
 405
 406   uint8 num_pps;
 407   RCHECK(reader->Read1(&num_pps));
 408
 409   pps_list.resize(num_pps);
 410   for (int i = 0; i < num_pps; i++) {
 411     uint16 pps_length;
 412     RCHECK(reader->Read2(&pps_length) &&
 413            reader->ReadVec(&pps_list[i], pps_length));
 414   }
 415
 416   return true;
 417 }
 418
 419 PixelAspectRatioBox::PixelAspectRatioBox() : h_spacing(1), v_spacing(1) {}
 420 PixelAspectRatioBox::~PixelAspectRatioBox() {}
 421 FourCC PixelAspectRatioBox::BoxType() const { return FOURCC_PASP; }
 422
 423 bool PixelAspectRatioBox::Parse(BoxReader* reader) {
 424   RCHECK(reader->Read4(&h_spacing) &&
 425          reader->Read4(&v_spacing));
 426   return true;
 427 }
 428
 429 VideoSampleEntry::VideoSampleEntry()
 430     : format(FOURCC_NULL),
 431       data_reference_index(0),
 432       width(0),
 433       height(0) {}
 434
 435 VideoSampleEntry::~VideoSampleEntry() {}
 436 FourCC VideoSampleEntry::BoxType() const {
 437   DCHECK(false) << "VideoSampleEntry should be parsed according to the "
 438                 << "handler type recovered in its Media ancestor.";
 439   return FOURCC_NULL;
 440 }
 441
 442 bool VideoSampleEntry::Parse(BoxReader* reader) {
 443   format = reader->type();
 444   RCHECK(reader->SkipBytes(6) &&
 445          reader->Read2(&data_reference_index) &&
 446          reader->SkipBytes(16) &&
 447          reader->Read2(&width) &&
 448          reader->Read2(&height) &&
 449          reader->SkipBytes(50));
 450
 451   RCHECK(reader->ScanChildren() &&
 452          reader->MaybeReadChild(&pixel_aspect));
 453
 454   if (format == FOURCC_ENCV) {
 455     // Continue scanning until a recognized protection scheme is found, or until
 456     // we run out of protection schemes.
 457     while (sinf.type.type != FOURCC_CENC) {
 458       if (!reader->ReadChild(&sinf))
 459         return false;
 460     }
 461   }
 462
 463   if (IsFormatValid())
 464     RCHECK(reader->ReadChild(&avcc));
 465
 466   return true;
 467 }
 468
 469 bool VideoSampleEntry::IsFormatValid() const {
 470   return format == FOURCC_AVC1 || format == FOURCC_AVC3 ||
 471       (format == FOURCC_ENCV && (sinf.format.format == FOURCC_AVC1 ||
 472                                  sinf.format.format == FOURCC_AVC3));
 473 }
 474
 475 ElementaryStreamDescriptor::ElementaryStreamDescriptor()
 476     : object_type(kForbidden) {}
 477
 478 ElementaryStreamDescriptor::~ElementaryStreamDescriptor() {}
 479
 480 FourCC ElementaryStreamDescriptor::BoxType() const {
 481   return FOURCC_ESDS;
 482 }
 483
 484 bool ElementaryStreamDescriptor::Parse(BoxReader* reader) {
 485   std::vector<uint8> data;
 486   ESDescriptor es_desc;
 487
 488   RCHECK(reader->ReadFullBoxHeader());
 489   RCHECK(reader->ReadVec(&data, reader->size() - reader->pos()));
 490   RCHECK(es_desc.Parse(data));
 491
 492   object_type = es_desc.object_type();
 493
 494   if (object_type != 0x40) {
 495     MEDIA_LOG(reader->log_cb()) << "Audio codec: mp4a."
 496                                 << std::hex << static_cast<int>(object_type);
 497   }
 498
 499   if (es_desc.IsAAC(object_type))
 500     RCHECK(aac.Parse(es_desc.decoder_specific_info(), reader->log_cb()));
 501
 502   return true;
 503 }
 504
 505 AudioSampleEntry::AudioSampleEntry()
 506     : format(FOURCC_NULL),
 507       data_reference_index(0),
 508       channelcount(0),
 509       samplesize(0),
 510       samplerate(0) {}
 511
 512 AudioSampleEntry::~AudioSampleEntry() {}
 513
 514 FourCC AudioSampleEntry::BoxType() const {
 515   DCHECK(false) << "AudioSampleEntry should be parsed according to the "
 516                 << "handler type recovered in its Media ancestor.";
 517   return FOURCC_NULL;
 518 }
 519
 520 bool AudioSampleEntry::Parse(BoxReader* reader) {
 521   format = reader->type();
 522   RCHECK(reader->SkipBytes(6) &&
 523          reader->Read2(&data_reference_index) &&
 524          reader->SkipBytes(8) &&
 525          reader->Read2(&channelcount) &&
 526          reader->Read2(&samplesize) &&
 527          reader->SkipBytes(4) &&
 528          reader->Read4(&samplerate));
 529   // Convert from 16.16 fixed point to integer
 530   samplerate >>= 16;
 531
 532   RCHECK(reader->ScanChildren());
 533   if (format == FOURCC_ENCA) {
 534     // Continue scanning until a recognized protection scheme is found, or until
 535     // we run out of protection schemes.
 536     while (sinf.type.type != FOURCC_CENC) {
 537       if (!reader->ReadChild(&sinf))
 538         return false;
 539     }
 540   }
 541
 542   // ESDS is not valid in case of EAC3.
 543   RCHECK(reader->MaybeReadChild(&esds));
 544   return true;
 545 }
 546
 547 MediaHeader::MediaHeader()
 548     : creation_time(0),
 549       modification_time(0),
 550       timescale(0),
 551       duration(0) {}
 552 MediaHeader::~MediaHeader() {}
 553 FourCC MediaHeader::BoxType() const { return FOURCC_MDHD; }
 554
 555 bool MediaHeader::Parse(BoxReader* reader) {
 556   RCHECK(reader->ReadFullBoxHeader());
 557
 558   if (reader->version() == 1) {
 559     RCHECK(reader->Read8(&creation_time) &&
 560            reader->Read8(&modification_time) &&
 561            reader->Read4(&timescale) &&
 562            reader->Read8(&duration));
 563   } else {
 564     RCHECK(reader->Read4Into8(&creation_time) &&
 565            reader->Read4Into8(&modification_time) &&
 566            reader->Read4(&timescale) &&
 567            reader->Read4Into8(&duration));
 568   }
 569   // Skip language information
 570   return reader->SkipBytes(4);
 571 }
 572
 573 MediaInformation::MediaInformation() {}
 574 MediaInformation::~MediaInformation() {}
 575 FourCC MediaInformation::BoxType() const { return FOURCC_MINF; }
 576
 577 bool MediaInformation::Parse(BoxReader* reader) {
 578   return reader->ScanChildren() &&
 579          reader->ReadChild(&sample_table);
 580 }
 581
 582 Media::Media() {}
 583 Media::~Media() {}
 584 FourCC Media::BoxType() const { return FOURCC_MDIA; }
 585
 586 bool Media::Parse(BoxReader* reader) {
 587   RCHECK(reader->ScanChildren() &&
 588          reader->ReadChild(&header) &&
 589          reader->ReadChild(&handler));
 590
 591   // Maddeningly, the HandlerReference box specifies how to parse the
 592   // SampleDescription box, making the latter the only box (of those that we
 593   // support) which cannot be parsed correctly on its own (or even with
 594   // information from its strict ancestor tree). We thus copy the handler type
 595   // to the sample description box *before* parsing it to provide this
 596   // information while parsing.
 597   information.sample_table.description.type = handler.type;
 598   RCHECK(reader->ReadChild(&information));
 599   return true;
 600 }
 601
 602 Track::Track() {}
 603 Track::~Track() {}
 604 FourCC Track::BoxType() const { return FOURCC_TRAK; }
 605
 606 bool Track::Parse(BoxReader* reader) {
 607   RCHECK(reader->ScanChildren() &&
 608          reader->ReadChild(&header) &&
 609          reader->ReadChild(&media) &&
 610          reader->MaybeReadChild(&edit));
 611   return true;
 612 }
 613
 614 MovieExtendsHeader::MovieExtendsHeader() : fragment_duration(0) {}
 615 MovieExtendsHeader::~MovieExtendsHeader() {}
 616 FourCC MovieExtendsHeader::BoxType() const { return FOURCC_MEHD; }
 617
 618 bool MovieExtendsHeader::Parse(BoxReader* reader) {
 619   RCHECK(reader->ReadFullBoxHeader());
 620   if (reader->version() == 1) {
 621     RCHECK(reader->Read8(&fragment_duration));
 622   } else {
 623     RCHECK(reader->Read4Into8(&fragment_duration));
 624   }
 625   return true;
 626 }
 627
 628 TrackExtends::TrackExtends()
 629     : track_id(0),
 630       default_sample_description_index(0),
 631       default_sample_duration(0),
 632       default_sample_size(0),
 633       default_sample_flags(0) {}
 634 TrackExtends::~TrackExtends() {}
 635 FourCC TrackExtends::BoxType() const { return FOURCC_TREX; }
 636
 637 bool TrackExtends::Parse(BoxReader* reader) {
 638   RCHECK(reader->ReadFullBoxHeader() &&
 639          reader->Read4(&track_id) &&
 640          reader->Read4(&default_sample_description_index) &&
 641          reader->Read4(&default_sample_duration) &&
 642          reader->Read4(&default_sample_size) &&
 643          reader->Read4(&default_sample_flags));
 644   return true;
 645 }
 646
 647 MovieExtends::MovieExtends() {}
 648 MovieExtends::~MovieExtends() {}
 649 FourCC MovieExtends::BoxType() const { return FOURCC_MVEX; }
 650
 651 bool MovieExtends::Parse(BoxReader* reader) {
 652   header.fragment_duration = 0;
 653   return reader->ScanChildren() &&
 654          reader->MaybeReadChild(&header) &&
 655          reader->ReadChildren(&tracks);
 656 }
 657
 658 Movie::Movie() : fragmented(false) {}
 659 Movie::~Movie() {}
 660 FourCC Movie::BoxType() const { return FOURCC_MOOV; }
 661
 662 bool Movie::Parse(BoxReader* reader) {
 663   return reader->ScanChildren() &&
 664          reader->ReadChild(&header) &&
 665          reader->ReadChildren(&tracks) &&
 666          // Media Source specific: 'mvex' required
 667          reader->ReadChild(&extends) &&
 668          reader->MaybeReadChildren(&pssh);
 669 }
 670
 671 TrackFragmentDecodeTime::TrackFragmentDecodeTime() : decode_time(0) {}
 672 TrackFragmentDecodeTime::~TrackFragmentDecodeTime() {}
 673 FourCC TrackFragmentDecodeTime::BoxType() const { return FOURCC_TFDT; }
 674
 675 bool TrackFragmentDecodeTime::Parse(BoxReader* reader) {
 676   RCHECK(reader->ReadFullBoxHeader());
 677   if (reader->version() == 1)
 678     return reader->Read8(&decode_time);
 679   else
 680     return reader->Read4Into8(&decode_time);
 681 }
 682
 683 MovieFragmentHeader::MovieFragmentHeader() : sequence_number(0) {}
 684 MovieFragmentHeader::~MovieFragmentHeader() {}
 685 FourCC MovieFragmentHeader::BoxType() const { return FOURCC_MFHD; }
 686
 687 bool MovieFragmentHeader::Parse(BoxReader* reader) {
 688   return reader->SkipBytes(4) && reader->Read4(&sequence_number);
 689 }
 690
 691 TrackFragmentHeader::TrackFragmentHeader()
 692     : track_id(0),
 693       sample_description_index(0),
 694       default_sample_duration(0),
 695       default_sample_size(0),
 696       default_sample_flags(0),
 697       has_default_sample_flags(false) {}
 698
 699 TrackFragmentHeader::~TrackFragmentHeader() {}
 700 FourCC TrackFragmentHeader::BoxType() const { return FOURCC_TFHD; }
 701
 702 bool TrackFragmentHeader::Parse(BoxReader* reader) {
 703   RCHECK(reader->ReadFullBoxHeader() && reader->Read4(&track_id));
 704
 705   // Media Source specific: reject tracks that set 'base-data-offset-present'.
 706   // Although the Media Source requires that 'default-base-is-moof' (14496-12
 707   // Amendment 2) be set, we omit this check as many otherwise-valid files in
 708   // the wild don't set it.
 709   //
 710   //  RCHECK((flags & 0x020000) && !(flags & 0x1));
 711   RCHECK(!(reader->flags() & 0x1));
 712
 713   if (reader->flags() & 0x2) {
 714     RCHECK(reader->Read4(&sample_description_index));
 715   } else {
 716     sample_description_index = 0;
 717   }
 718
 719   if (reader->flags() & 0x8) {
 720     RCHECK(reader->Read4(&default_sample_duration));
 721   } else {
 722     default_sample_duration = 0;
 723   }
 724
 725   if (reader->flags() & 0x10) {
 726     RCHECK(reader->Read4(&default_sample_size));
 727   } else {
 728     default_sample_size = 0;
 729   }
 730
 731   if (reader->flags() & 0x20) {
 732     RCHECK(reader->Read4(&default_sample_flags));
 733     has_default_sample_flags = true;
 734   } else {
 735     has_default_sample_flags = false;
 736   }
 737
 738   return true;
 739 }
 740
 741 TrackFragmentRun::TrackFragmentRun()
 742     : sample_count(0), data_offset(0) {}
 743 TrackFragmentRun::~TrackFragmentRun() {}
 744 FourCC TrackFragmentRun::BoxType() const { return FOURCC_TRUN; }
 745
 746 bool TrackFragmentRun::Parse(BoxReader* reader) {
 747   RCHECK(reader->ReadFullBoxHeader() &&
 748          reader->Read4(&sample_count));
 749   const uint32 flags = reader->flags();
 750
 751   bool data_offset_present = (flags & 0x1) != 0;
 752   bool first_sample_flags_present = (flags & 0x4) != 0;
 753   bool sample_duration_present = (flags & 0x100) != 0;
 754   bool sample_size_present = (flags & 0x200) != 0;
 755   bool sample_flags_present = (flags & 0x400) != 0;
 756   bool sample_composition_time_offsets_present = (flags & 0x800) != 0;
 757
 758   if (data_offset_present) {
 759     RCHECK(reader->Read4(&data_offset));
 760   } else {
 761     data_offset = 0;
 762   }
 763
 764   uint32 first_sample_flags = 0;
 765   if (first_sample_flags_present)
 766     RCHECK(reader->Read4(&first_sample_flags));
 767
 768   int fields = sample_duration_present + sample_size_present +
 769       sample_flags_present + sample_composition_time_offsets_present;
 770   RCHECK(reader->HasBytes(fields * sample_count));
 771
 772   if (sample_duration_present)
 773     sample_durations.resize(sample_count);
 774   if (sample_size_present)
 775     sample_sizes.resize(sample_count);
 776   if (sample_flags_present)
 777     sample_flags.resize(sample_count);
 778   if (sample_composition_time_offsets_present)
 779     sample_composition_time_offsets.resize(sample_count);
 780
 781   for (uint32 i = 0; i < sample_count; ++i) {
 782     if (sample_duration_present)
 783       RCHECK(reader->Read4(&sample_durations[i]));
 784     if (sample_size_present)
 785       RCHECK(reader->Read4(&sample_sizes[i]));
 786     if (sample_flags_present)
 787       RCHECK(reader->Read4(&sample_flags[i]));
 788     if (sample_composition_time_offsets_present)
 789       RCHECK(reader->Read4s(&sample_composition_time_offsets[i]));
 790   }
 791
 792   if (first_sample_flags_present) {
 793     if (sample_flags.size() == 0) {
 794       sample_flags.push_back(first_sample_flags);
 795     } else {
 796       sample_flags[0] = first_sample_flags;
 797     }
 798   }
 799   return true;
 800 }
 801
 802 SampleToGroup::SampleToGroup() : grouping_type(0), grouping_type_parameter(0) {}
 803 SampleToGroup::~SampleToGroup() {}
 804 FourCC SampleToGroup::BoxType() const { return FOURCC_SBGP; }
 805
 806 bool SampleToGroup::Parse(BoxReader* reader) {
 807   RCHECK(reader->ReadFullBoxHeader() &&
 808          reader->Read4(&grouping_type));
 809
 810   if (reader->version() == 1)
 811     RCHECK(reader->Read4(&grouping_type_parameter));
 812
 813   if (grouping_type != FOURCC_SEIG) {
 814     DLOG(WARNING) << "SampleToGroup box with grouping_type '" << grouping_type
 815                   << "' is not supported.";
 816     return true;
 817   }
 818
 819   uint32 count;
 820   RCHECK(reader->Read4(&count));
 821   entries.resize(count);
 822   for (uint32 i = 0; i < count; ++i) {
 823     RCHECK(reader->Read4(&entries[i].sample_count) &&
 824            reader->Read4(&entries[i].group_description_index));
 825   }
 826   return true;
 827 }
 828
 829 CencSampleEncryptionInfoEntry::CencSampleEncryptionInfoEntry()
 830     : is_encrypted(false), iv_size(0) {}
 831 CencSampleEncryptionInfoEntry::~CencSampleEncryptionInfoEntry() {}
 832
 833 SampleGroupDescription::SampleGroupDescription() : grouping_type(0) {}
 834 SampleGroupDescription::~SampleGroupDescription() {}
 835 FourCC SampleGroupDescription::BoxType() const { return FOURCC_SGPD; }
 836
 837 bool SampleGroupDescription::Parse(BoxReader* reader) {
 838   RCHECK(reader->ReadFullBoxHeader() &&
 839          reader->Read4(&grouping_type));
 840
 841   if (grouping_type != FOURCC_SEIG) {
 842     DLOG(WARNING) << "SampleGroupDescription box with grouping_type '"
 843                   << grouping_type << "' is not supported.";
 844     return true;
 845   }
 846
 847   const uint8 version = reader->version();
 848
 849   const size_t kKeyIdSize = 16;
 850   const size_t kEntrySize = sizeof(uint32) + kKeyIdSize;
 851   uint32 default_length = 0;
 852   if (version == 1) {
 853       RCHECK(reader->Read4(&default_length));
 854       RCHECK(default_length == 0 || default_length >= kEntrySize);
 855   }
 856
 857   uint32 count;
 858   RCHECK(reader->Read4(&count));
 859   entries.resize(count);
 860   for (uint32 i = 0; i < count; ++i) {
 861     if (version == 1) {
 862       if (default_length == 0) {
 863         uint32 description_length = 0;
 864         RCHECK(reader->Read4(&description_length));
 865         RCHECK(description_length >= kEntrySize);
 866       }
 867     }
 868
 869     uint8 flag;
 870     RCHECK(reader->SkipBytes(2) &&  // reserved.
 871            reader->Read1(&flag) &&
 872            reader->Read1(&entries[i].iv_size) &&
 873            reader->ReadVec(&entries[i].key_id, kKeyIdSize));
 874
 875     entries[i].is_encrypted = (flag != 0);
 876     if (entries[i].is_encrypted) {
 877       RCHECK(entries[i].iv_size == 8 || entries[i].iv_size == 16);
 878     } else {
 879       RCHECK(entries[i].iv_size == 0);
 880     }
 881   }
 882   return true;
 883 }
 884
 885 TrackFragment::TrackFragment() {}
 886 TrackFragment::~TrackFragment() {}
 887 FourCC TrackFragment::BoxType() const { return FOURCC_TRAF; }
 888
 889 bool TrackFragment::Parse(BoxReader* reader) {
 890   RCHECK(reader->ScanChildren() &&
 891          reader->ReadChild(&header) &&
 892          // Media Source specific: 'tfdt' required
 893          reader->ReadChild(&decode_time) &&
 894          reader->MaybeReadChildren(&runs) &&
 895          reader->MaybeReadChild(&auxiliary_offset) &&
 896          reader->MaybeReadChild(&auxiliary_size) &&
 897          reader->MaybeReadChild(&sdtp));
 898
 899   // There could be multiple SampleGroupDescription and SampleToGroup boxes with
 900   // different grouping types. For common encryption, the relevant grouping type
 901   // is 'seig'. Continue reading until 'seig' is found, or until running out of
 902   // child boxes.
 903   while (sample_group_description.grouping_type != FOURCC_SEIG &&
 904          reader->HasChild(&sample_group_description)) {
 905     RCHECK(reader->ReadChild(&sample_group_description));
 906   }
 907   while (sample_to_group.grouping_type != FOURCC_SEIG &&
 908          reader->HasChild(&sample_to_group)) {
 909     RCHECK(reader->ReadChild(&sample_to_group));
 910   }
 911   return true;
 912 }
 913
 914 MovieFragment::MovieFragment() {}
 915 MovieFragment::~MovieFragment() {}
 916 FourCC MovieFragment::BoxType() const { return FOURCC_MOOF; }
 917
 918 bool MovieFragment::Parse(BoxReader* reader) {
 919   RCHECK(reader->ScanChildren() &&
 920          reader->ReadChild(&header) &&
 921          reader->ReadChildren(&tracks) &&
 922          reader->MaybeReadChildren(&pssh));
 923   return true;
 924 }
 925
 926 IndependentAndDisposableSamples::IndependentAndDisposableSamples() {}
 927 IndependentAndDisposableSamples::~IndependentAndDisposableSamples() {}
 928 FourCC IndependentAndDisposableSamples::BoxType() const { return FOURCC_SDTP; }
 929
 930 bool IndependentAndDisposableSamples::Parse(BoxReader* reader) {
 931   RCHECK(reader->ReadFullBoxHeader());
 932   RCHECK(reader->version() == 0);
 933   RCHECK(reader->flags() == 0);
 934
 935   int sample_count = reader->size() - reader->pos();
 936   sample_depends_on_.resize(sample_count);
 937   for (int i = 0; i < sample_count; ++i) {
 938     uint8 sample_info;
 939     RCHECK(reader->Read1(&sample_info));
 940
 941     sample_depends_on_[i] =
 942         static_cast<SampleDependsOn>((sample_info >> 4) & 0x3);
 943
 944     RCHECK(sample_depends_on_[i] != kSampleDependsOnReserved);
 945   }
 946
 947   return true;
 948 }
 949
 950 SampleDependsOn IndependentAndDisposableSamples::sample_depends_on(
 951     size_t i) const {
 952   if (i >= sample_depends_on_.size())
 953     return kSampleDependsOnUnknown;
 954
 955   return sample_depends_on_[i];
 956 }
 957
 958 }  // namespace mp4
 959 }  // namespace media