Implement ISO BMFF support in Media Source.

media/mp4/box_definitions.cc

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "media/mp4/box_definitions.h"
+
+#include "base/logging.h"
+#include "media/mp4/box_reader.h"
+#include "media/mp4/fourccs.h"
+#include "media/mp4/rcheck.h"
+
+namespace media {
+namespace mp4 {
+
+bool FileType::Parse(BoxReader* reader) {
+  RCHECK(reader->ReadFourCC(&major_brand) && reader->Read4(&minor_version));
+  size_t num_brands = (reader->size() - reader->pos()) / sizeof(FourCC);
+  return reader->SkipBytes(sizeof(FourCC) * num_brands);  // compatible_brands
+}
+
+ProtectionSystemSpecificHeader::ProtectionSystemSpecificHeader() {}
+ProtectionSystemSpecificHeader::~ProtectionSystemSpecificHeader() {}
+FourCC ProtectionSystemSpecificHeader::BoxType() const { return FOURCC_PSSH; }
+
+bool ProtectionSystemSpecificHeader::Parse(BoxReader* reader) {
+  uint32 size;
+  return reader->SkipBytes(4) &&
+         reader->ReadVec(&system_id, 16) &&
+         reader->Read4(&size) &&
+         reader->ReadVec(&data, size);
+}
+
+SampleAuxiliaryInformationOffset::SampleAuxiliaryInformationOffset() {}
+SampleAuxiliaryInformationOffset::~SampleAuxiliaryInformationOffset() {}
+FourCC SampleAuxiliaryInformationOffset::BoxType() const { return FOURCC_SAIO; }
+
+bool SampleAuxiliaryInformationOffset::Parse(BoxReader* reader) {
+  RCHECK(reader->ReadFullBoxHeader());
+  if (reader->flags() & 1)
+    RCHECK(reader->SkipBytes(8));
+
+  uint32 count;
+  RCHECK(reader->Read4(&count) &&
+         reader->HasBytes(count * (reader->version() == 1 ? 8 : 4)));
+  offsets.resize(count);
+
+  for (uint32 i = 0; i < count; i++) {
+    if (reader->version() == 1) {
+      RCHECK(reader->Read8(&offsets[i]));
+    } else {
+      RCHECK(reader->Read4Into8(&offsets[i]));
+    }
+  }
+  return true;
+}
+
+SampleAuxiliaryInformationSize::SampleAuxiliaryInformationSize()
+  : default_sample_info_size(0), sample_count(0) {
+}
+SampleAuxiliaryInformationSize::~SampleAuxiliaryInformationSize() {}
+FourCC SampleAuxiliaryInformationSize::BoxType() const { return FOURCC_SAIZ; }
+
+bool SampleAuxiliaryInformationSize::Parse(BoxReader* reader) {
+  RCHECK(reader->ReadFullBoxHeader());
+  if (reader->flags() & 1)
+    RCHECK(reader->SkipBytes(8));
+
+  RCHECK(reader->Read1(&default_sample_info_size) &&
+         reader->Read4(&sample_count));
+  if (default_sample_info_size == 0)
+    return reader->ReadVec(&sample_info_sizes, sample_count);
+  return true;
+}
+
+OriginalFormat::OriginalFormat() {}
+OriginalFormat::~OriginalFormat() {}
+FourCC OriginalFormat::BoxType() const { return FOURCC_FRMA; }
+
+bool OriginalFormat::Parse(BoxReader* reader) {
+  return reader->ReadFourCC(&format);
+}
+
+SchemeType::SchemeType() {}
+SchemeType::~SchemeType() {}
+FourCC SchemeType::BoxType() const { return FOURCC_SCHM; }
+
+bool SchemeType::Parse(BoxReader* reader) {
+  RCHECK(reader->SkipBytes(4) &&
+         reader->ReadFourCC(&type) &&
+         reader->Read4(&version));
+  RCHECK(type == FOURCC_CENC);
+  return true;
+}
+
+TrackEncryption::TrackEncryption()
+  : is_encrypted(false), default_iv_size(0) {
+}
+TrackEncryption::~TrackEncryption() {}
+FourCC TrackEncryption::BoxType() const { return FOURCC_TENC; }
+
+bool TrackEncryption::Parse(BoxReader* reader) {
+  uint8 flag;
+  RCHECK(reader->SkipBytes(2) &&
+         reader->Read1(&flag) &&
+         reader->Read1(&default_iv_size) &&
+         reader->ReadVec(&default_kid, 16));
+  is_encrypted = (flag != 0);
+  if (is_encrypted) {
+    RCHECK(default_iv_size == 8 || default_iv_size == 16);
+  } else {
+    RCHECK(default_iv_size == 0);
+  }
+  return true;
+}
+
+SchemeInfo::SchemeInfo() {}
+SchemeInfo::~SchemeInfo() {}
+FourCC SchemeInfo::BoxType() const { return FOURCC_SCHI; }
+
+bool SchemeInfo::Parse(BoxReader* reader) {
+  return reader->ScanChildren() && reader->ReadChild(&track_encryption);
+}
+
+ProtectionSchemeInfo::ProtectionSchemeInfo() {}
+ProtectionSchemeInfo::~ProtectionSchemeInfo() {}
+FourCC ProtectionSchemeInfo::BoxType() const { return FOURCC_SINF; }
+
+bool ProtectionSchemeInfo::Parse(BoxReader* reader) {
+  return reader->ScanChildren() &&
+         reader->ReadChild(&type) &&
+         reader->ReadChild(&info);
+}
+
+MovieHeader::MovieHeader() {}
+MovieHeader::~MovieHeader() {}
+FourCC MovieHeader::BoxType() const { return FOURCC_MVHD; }
+
+bool MovieHeader::Parse(BoxReader* reader) {
+  RCHECK(reader->ReadFullBoxHeader());
+
+  if (reader->version() == 1) {
+    RCHECK(reader->Read8(&creation_time) &&
+           reader->Read8(&modification_time) &&
+           reader->Read4(&timescale) &&
+           reader->Read8(&duration));
+  } else {
+    RCHECK(reader->Read4Into8(&creation_time) &&
+           reader->Read4Into8(&modification_time) &&
+           reader->Read4(&timescale) &&
+           reader->Read4Into8(&duration));
+  }
+
+  RCHECK(reader->Read4s(&rate) &&
+         reader->Read2s(&volume) &&
+         reader->SkipBytes(10) &&  // reserved
+         reader->SkipBytes(36) &&  // matrix
+         reader->SkipBytes(24) &&  // predefined zero
+         reader->Read4(&next_track_id));
+  return true;
+}
+
+TrackHeader::TrackHeader() {}
+TrackHeader::~TrackHeader() {}
+FourCC TrackHeader::BoxType() const { return FOURCC_TKHD; }
+
+bool TrackHeader::Parse(BoxReader* reader) {
+  RCHECK(reader->ReadFullBoxHeader());
+  if (reader->version() == 1) {
+    RCHECK(reader->Read8(&creation_time) &&
+           reader->Read8(&modification_time) &&
+           reader->Read4(&track_id) &&
+           reader->SkipBytes(4) &&    // reserved
+           reader->Read8(&duration));
+  } else {
+    RCHECK(reader->Read4Into8(&creation_time) &&
+           reader->Read4Into8(&modification_time) &&
+           reader->Read4(&track_id) &&
+           reader->SkipBytes(4) &&   // reserved
+           reader->Read4Into8(&duration));
+  }
+
+  RCHECK(reader->SkipBytes(8) &&  // reserved
+         reader->Read2s(&layer) &&
+         reader->Read2s(&alternate_group) &&
+         reader->Read2s(&volume) &&
+         reader->SkipBytes(2) &&  // reserved
+         reader->SkipBytes(36) &&  // matrix
+         reader->Read4(&width) &&
+         reader->Read4(&height));
+  width >>= 16;
+  height >>= 16;
+  return true;
+}
+
+SampleDescription::SampleDescription() {}
+SampleDescription::~SampleDescription() {}
+FourCC SampleDescription::BoxType() const { return FOURCC_STSD; }
+
+bool SampleDescription::Parse(BoxReader* reader) {
+  uint32 count;
+  RCHECK(reader->SkipBytes(4) &&
+         reader->Read4(&count) &&
+         reader->ScanChildren());
+  video_entries.clear();
+  audio_entries.clear();
+
+  // Note: this value is preset before scanning begins. See comments in the
+  // Parse(Media*) function.
+  if (type == kVideo) {
+    RCHECK(reader->ReadAllChildren(&video_entries));
+  } else if (type == kAudio) {
+    RCHECK(reader->ReadAllChildren(&audio_entries));
+  }
+  return true;
+}
+
+SampleTable::SampleTable() {}
+SampleTable::~SampleTable() {}
+FourCC SampleTable::BoxType() const { return FOURCC_STBL; }
+
+bool SampleTable::Parse(BoxReader* reader) {
+  return reader->ScanChildren() &&
+         reader->ReadChild(&description);
+}
+
+EditList::EditList() {}
+EditList::~EditList() {}
+FourCC EditList::BoxType() const { return FOURCC_ELST; }
+
+bool EditList::Parse(BoxReader* reader) {
+  uint32 count;
+  RCHECK(reader->ReadFullBoxHeader() && reader->Read4(&count));
+
+  if (reader->version() == 1) {
+    RCHECK(reader->HasBytes(count * 20));
+  } else {
+    RCHECK(reader->HasBytes(count * 12));
+  }
+  edits.resize(count);
+
+  for (auto edit = edits.begin(); edit != edits.end(); ++edit) {
+    if (reader->version() == 1) {
+      RCHECK(reader->Read8(&edit->segment_duration) &&
+             reader->Read8s(&edit->media_time));
+    } else {
+      RCHECK(reader->Read4Into8(&edit->segment_duration) &&
+             reader->Read4sInto8s(&edit->media_time));
+    }
+    RCHECK(reader->Read2s(&edit->media_rate_integer) &&
+           reader->Read2s(&edit->media_rate_fraction));
+  }
+  return true;
+}
+
+Edit::Edit() {}
+Edit::~Edit() {}
+FourCC Edit::BoxType() const { return FOURCC_EDTS; }
+
+bool Edit::Parse(BoxReader* reader) {
+  return reader->ScanChildren() && reader->ReadChild(&list);
+}
+
+HandlerReference::HandlerReference() {}
+HandlerReference::~HandlerReference() {}
+FourCC HandlerReference::BoxType() const { return FOURCC_HDLR; }
+
+bool HandlerReference::Parse(BoxReader* reader) {
+  FourCC hdlr_type;
+  RCHECK(reader->SkipBytes(8) && reader->ReadFourCC(&hdlr_type));
+  // Note: remaining fields in box ignored
+  if (hdlr_type == FOURCC_VIDE) {
+    type = kVideo;
+  } else if (hdlr_type == FOURCC_SOUN) {
+    type = kAudio;
+  } else {
+    type = kInvalid;
+  }
+  return true;
+}
+
+AVCDecoderConfigurationRecord::AVCDecoderConfigurationRecord() {};

[acolwell GONE FROM CHROMIUM, 2012/06/08 16:10:38]

lint nit: remove ;

[strobe_, 2012/06/11 18:44:21]

Done.

+AVCDecoderConfigurationRecord::~AVCDecoderConfigurationRecord() {};

[acolwell GONE FROM CHROMIUM, 2012/06/08 16:10:38]

lint nit: remove ;

[strobe_, 2012/06/11 18:44:21]

Done.

+FourCC AVCDecoderConfigurationRecord::BoxType() const { return FOURCC_AVCC; }
+
+bool AVCDecoderConfigurationRecord::Parse(BoxReader* readereader) {
+  RCHECK(readereader->Read1(&version) && version == 1 &&

[acolwell GONE FROM CHROMIUM, 2012/06/08 16:10:38]

Oops :) readereader -> reader 

[strobe_, 2012/06/11 18:44:21]

Heh. Done.

+         readereader->Read1(&profile_indication) &&
+         readereader->Read1(&profile_compatibility) &&
+         readereader->Read1(&avc_level));
+
+  uint8 length_size_minus_one;
+  RCHECK(readereader->Read1(&length_size_minus_one) &&
+         (length_size_minus_one & 0xfc) == 0xfc);
+  length_size = (length_size_minus_one & 0x3) + 1;
+
+  uint8 num_sps;
+  RCHECK(readereader->Read1(&num_sps) && (num_sps & 0xe0) == 0xe0);
+  num_sps &= 0x1f;
+
+  sps_list.resize(num_sps);
+  for (int i = 0; i < num_sps; i++) {
+    uint16 sps_length;
+    RCHECK(readereader->Read2(&sps_length) &&
+           readereader->ReadVec(&sps_list[i], sps_length));
+  }
+
+  uint8 num_pps;
+  RCHECK(readereader->Read1(&num_pps));
+
+  pps_list.resize(num_pps);
+  for (int i = 0; i < num_pps; i++) {
+    uint16 pps_length;
+    RCHECK(readereader->Read2(&pps_length) &&
+           readereader->ReadVec(&pps_list[i], pps_length));
+  }
+
+  return true;
+}
+
+VideoSampleEntry::VideoSampleEntry() {}
+VideoSampleEntry::~VideoSampleEntry() {}
+FourCC VideoSampleEntry::BoxType() const {
+  DCHECK(false) << "VideoSampleEntry should be parsed according to the "
+                << "handler type recovered in its Media ancestor.";
+  return FOURCC_NULL;
+}
+
+bool VideoSampleEntry::Parse(BoxReader* reader) {
+  format = reader->type();
+  RCHECK(reader->SkipBytes(6) &&
+         reader->Read2(&data_reference_index) &&
+         reader->SkipBytes(16) &&
+         reader->Read2(&width) &&
+         reader->Read2(&height) &&
+         reader->SkipBytes(50));
+
+  RCHECK(reader->ScanChildren());
+  if (format == FOURCC_ENCV) {
+    RCHECK(reader->ReadChild(&sinf));
+  }
+
+  // TODO(strobe): Widevine test files do not follow spec here; check disabled

[acolwell GONE FROM CHROMIUM, 2012/06/08 16:10:38]

lint nit: 2 spaces after // here and below

[strobe_, 2012/06/11 18:44:21]

Done.

+  //if (format == FOURCC_AVC1 ||
+  //    (format == FOURCC_ENCV &&
+  //     sinf.format.format == FOURCC_AVC1)) {
+    RCHECK(reader->ReadChild(&avcc));
+  //}
+  return true;
+}
+
+AudioSampleEntry::AudioSampleEntry() {}
+AudioSampleEntry::~AudioSampleEntry() {}
+FourCC AudioSampleEntry::BoxType() const {
+  DCHECK(false) << "AudioSampleEntry should be parsed according to the "
+                << "handler type recovered in its Media ancestor.";
+  return FOURCC_NULL;
+}
+
+bool AudioSampleEntry::Parse(BoxReader* reader) {
+  format = reader->type();
+  RCHECK(reader->SkipBytes(6) &&
+         reader->Read2(&data_reference_index) &&
+         reader->SkipBytes(8) &&
+         reader->Read2(&channelcount) &&
+         reader->Read2(&samplesize) &&
+         reader->SkipBytes(4) &&
+         reader->Read4(&samplerate));
+  // Convert from 16.16 fixed point to integer
+  samplerate >>= 16;

[acolwell GONE FROM CHROMIUM, 2012/06/08 16:10:38]

How does mp4 handle 96kHz audio?

[strobe_, 2012/06/11 18:44:21]

Poorly. ;)

BMFF supports a lot of crazy things, but this doesn't seem to be one of them (at
least from the specs I have seen). It's certainly conceivable that some audio
formats (e.g. AAC, DTS) might store alternate configs in either a
format-specific box (ESDS) or simply plop them inline in a stream, and expect
that the decoder will override the values in the container somehow. As for
real-world examples, FFmpeg at least refuses to create an MP4 with 96k audio.

If we need to, we can pull apart the first few bytes of the codec or the ESDS
(if present) to grab the "real" information, but I'd prefer to avoid bending
over backwards to support non-spec files.

[acolwell GONE FROM CHROMIUM, 2012/06/13 14:16:06]

Ok. I'm fine with leaving this code as is for now. I agree it isn't worth
jumping through hoops for this right now.

+
+  RCHECK(reader->ScanChildren());
+  if (format == FOURCC_ENCA) {
+    RCHECK(reader->ReadChild(&sinf));
+  }
+  return true;
+}
+
+MediaHeader::MediaHeader() {}
+MediaHeader::~MediaHeader() {}
+FourCC MediaHeader::BoxType() const { return FOURCC_MDHD; }
+
+bool MediaHeader::Parse(BoxReader* reader) {
+  RCHECK(reader->ReadFullBoxHeader());
+
+  if (reader->version() == 1) {
+    RCHECK(reader->Read8(&creation_time) &&
+           reader->Read8(&modification_time) &&
+           reader->Read4(&timescale) &&
+           reader->Read8(&duration));
+  } else {
+    RCHECK(reader->Read4Into8(&creation_time) &&
+           reader->Read4Into8(&modification_time) &&
+           reader->Read4(&timescale) &&
+           reader->Read4Into8(&duration));
+  }
+  // Skip language information
+  return reader->SkipBytes(4);
+}
+
+MediaInformation::MediaInformation() {}
+MediaInformation::~MediaInformation() {}
+FourCC MediaInformation::BoxType() const { return FOURCC_MINF; }
+
+bool MediaInformation::Parse(BoxReader* reader) {
+  return reader->ScanChildren() &&
+         reader->ReadChild(&sample_table);
+}
+
+Media::Media() {}
+Media::~Media() {}
+FourCC Media::BoxType() const { return FOURCC_MDIA; }
+
+bool Media::Parse(BoxReader* reader) {
+  RCHECK(reader->ScanChildren() &&
+         reader->ReadChild(&header) &&
+         reader->ReadChild(&handler));
+
+  // Maddeningly, the HandlerReference box specifies how to parse the
+  // SampleDescription box, making the latter the only box (of those that we
+  // support) which cannot be parsed correctly on its own (or even with
+  // information from its strict ancestor tree). We thus copy the handler type
+  // to the sample description box *before* parsing it to provide this
+  // information while parsing.
+  information.sample_table.description.type = handler.type;
+  RCHECK(reader->ReadChild(&information));
+  return true;
+}
+
+Track::Track() {}
+Track::~Track() {}
+FourCC Track::BoxType() const { return FOURCC_TRAK; }
+
+bool Track::Parse(BoxReader* reader) {
+  RCHECK(reader->ScanChildren() &&
+         reader->ReadChild(&header) &&
+         reader->ReadChild(&media) &&
+         reader->MaybeReadChild(&edit));
+  return true;
+}
+
+MovieExtendsHeader::MovieExtendsHeader() {}
+MovieExtendsHeader::~MovieExtendsHeader() {}
+FourCC MovieExtendsHeader::BoxType() const { return FOURCC_MEHD; }
+
+bool MovieExtendsHeader::Parse(BoxReader* reader) {
+  RCHECK(reader->Read8(&fragment_duration));
+  return true;
+}
+
+TrackExtends::TrackExtends() {}
+TrackExtends::~TrackExtends() {}
+FourCC TrackExtends::BoxType() const { return FOURCC_TREX; }
+
+bool TrackExtends::Parse(BoxReader* reader) {
+  RCHECK(reader->ReadFullBoxHeader() &&
+         reader->Read4(&track_id) &&
+         reader->Read4(&default_sample_description_index) &&
+         reader->Read4(&default_sample_duration) &&
+         reader->Read4(&default_sample_size) &&
+         reader->Read4(&default_sample_flags));
+  return true;
+}
+
+MovieExtends::MovieExtends() {}
+MovieExtends::~MovieExtends() {}
+FourCC MovieExtends::BoxType() const { return FOURCC_MVEX; }
+
+bool MovieExtends::Parse(BoxReader* reader) {
+  header.fragment_duration = 0;
+  return reader->ScanChildren() &&
+         reader->MaybeReadChild(&header) &&
+         // TODO(strobe): does not detect correspondence rule (trex must match
+         // one-to-one with trak)
+         reader->ReadChildren(&tracks);
+}
+
+Movie::Movie() {};

[acolwell GONE FROM CHROMIUM, 2012/06/08 16:10:38]

lint nit: remove ;

[strobe_, 2012/06/11 18:44:21]

Done.

+Movie::~Movie() {};

[acolwell GONE FROM CHROMIUM, 2012/06/08 16:10:38]

lint nit: remove ;

[strobe_, 2012/06/11 18:44:21]

Done.

+FourCC Movie::BoxType() const { return FOURCC_MOOV; }
+
+bool Movie::Parse(BoxReader* reader) {
+  return reader->ScanChildren() &&
+         reader->ReadChild(&header) &&
+         reader->ReadChildren(&tracks) &&
+         // Media Source specific: 'mvex' required
+         reader->ReadChild(&extends) &&
+         reader->MaybeReadChildren(&pssh);
+}
+
+TrackFragmentDecodeTime::TrackFragmentDecodeTime() {}
+TrackFragmentDecodeTime::~TrackFragmentDecodeTime() {}
+FourCC TrackFragmentDecodeTime::BoxType() const { return FOURCC_TFDT; }
+
+bool TrackFragmentDecodeTime::Parse(BoxReader* reader) {
+  RCHECK(reader->ReadFullBoxHeader());
+  if (reader->version() == 1)
+    return reader->Read8(&decode_time);
+  else
+    return reader->Read4Into8(&decode_time);
+}
+
+MovieFragmentHeader::MovieFragmentHeader() {}
+MovieFragmentHeader::~MovieFragmentHeader() {}
+FourCC MovieFragmentHeader::BoxType() const { return FOURCC_MFHD; }
+
+bool MovieFragmentHeader::Parse(BoxReader* reader) {
+  return reader->SkipBytes(4) && reader->Read4(&sequence_number);
+}
+
+TrackFragmentHeader::TrackFragmentHeader() {}
+TrackFragmentHeader::~TrackFragmentHeader() {}
+FourCC TrackFragmentHeader::BoxType() const { return FOURCC_TFHD; }
+
+bool TrackFragmentHeader::Parse(BoxReader* reader) {
+  RCHECK(reader->ReadFullBoxHeader() && reader->Read4(&track_id));
+
+  // Media Source specific: we require that 'default-base-is-moof' (14496-12
+  // Amendment 2) be set, and reject tracks that set 'base-data-offset-present'.
+  //
+  // TODO(strobe): Test files do not have 'default-base-is-moof' set explicitly
+  // (although they are structured as if it is set). Because this flag is hidden
+  // in Amendment 2, it might not be set by all implementors. Should we reject
+  // such files, or try them anyway?
+  //
+  // RCHECK((flags & 0x020000) && !(flags & 0x1));
+  RCHECK(!(reader->flags() & 0x1));
+
+  if (reader->flags() & 0x2)
+    RCHECK(reader->SkipBytes(4));  // sample_description_index
+
+  if (reader->flags() & 0x8) {
+    RCHECK(reader->Read4(&default_sample_duration));
+  } else {
+    default_sample_duration = 0;
+  }
+
+  if (reader->flags() & 0x10) {
+    RCHECK(reader->Read4(&default_sample_size));
+  } else {
+    default_sample_size = 0;
+  }
+
+  if (reader->flags() & 0x20) {
+    RCHECK(reader->Read4(&default_sample_flags));
+    has_default_sample_flags = true;
+  } else {
+    has_default_sample_flags = false;
+  }
+
+  return true;
+}
+
+TrackFragmentRun::TrackFragmentRun() {}
+TrackFragmentRun::~TrackFragmentRun() {}
+FourCC TrackFragmentRun::BoxType() const { return FOURCC_TRUN; }
+
+bool TrackFragmentRun::Parse(BoxReader* reader) {
+  RCHECK(reader->ReadFullBoxHeader() &&
+         reader->Read4(&sample_count));
+  const uint32 flags = reader->flags();
+
+  bool data_offset_present = flags & 0x1;
+  bool first_sample_flags_present = flags & 0x4;
+  bool sample_duration_present = flags & 0x100;
+  bool sample_size_present = flags & 0x200;
+  bool sample_flags_present = flags & 0x400;
+  bool sample_composition_time_offsets_present = flags & 0x800;
+
+  if (data_offset_present) {
+    RCHECK(reader->Read4(&data_offset));
+  } else {
+    data_offset = 0;
+  }
+
+  uint32 first_sample_flags;
+  if (first_sample_flags_present)
+    RCHECK(reader->Read4(&first_sample_flags));
+
+  int fields = sample_duration_present + sample_size_present +
+      sample_flags_present + sample_composition_time_offsets_present;
+  RCHECK(reader->HasBytes(fields * sample_count));
+
+  if (sample_duration_present)
+    sample_durations.resize(sample_count);
+  if (sample_size_present)
+    sample_sizes.resize(sample_count);
+  if (sample_flags_present)
+    sample_flags.resize(sample_count);
+  if (sample_composition_time_offsets_present)
+    sample_composition_time_offsets.resize(sample_count);
+
+  for (uint32 i = 0; i < sample_count; ++i) {
+    if (sample_duration_present)
+      RCHECK(reader->Read4(&sample_durations[i]));
+    if (sample_size_present)
+      RCHECK(reader->Read4(&sample_sizes[i]));
+    if (sample_flags_present)
+      RCHECK(reader->Read4(&sample_flags[i]));
+    if (sample_composition_time_offsets_present)
+      RCHECK(reader->Read4(&sample_composition_time_offsets[i]));
+  }
+
+  if (first_sample_flags_present) {
+    if (sample_flags.size() == 0) {
+      sample_flags.push_back(first_sample_flags);
+    } else {
+      sample_flags[0] = first_sample_flags;
+    }
+  }
+  return true;
+}
+
+TrackFragment::TrackFragment() {}
+TrackFragment::~TrackFragment() {}
+FourCC TrackFragment::BoxType() const { return FOURCC_TRAF; }
+
+bool TrackFragment::Parse(BoxReader* reader) {
+  return reader->ScanChildren() &&
+         reader->ReadChild(&header) &&
+         // Media Source specific: 'tfdt' required
+         reader->ReadChild(&decode_time) &&
+         reader->MaybeReadChildren(&runs) &&
+         reader->MaybeReadChild(&auxiliary_offset) &&
+         reader->MaybeReadChild(&auxiliary_size);
+}
+
+MovieFragment::MovieFragment() {}
+MovieFragment::~MovieFragment() {}
+FourCC MovieFragment::BoxType() const { return FOURCC_MOOF; }
+
+bool MovieFragment::Parse(BoxReader* reader) {
+  RCHECK(reader->ScanChildren() &&
+         reader->ReadChild(&header) &&
+         reader->ReadChildren(&tracks) &&
+         reader->MaybeReadChildren(&pssh));
+  return true;
+}
+
+}  // namespace mp4
+}  // namespace media