Matroska Media Container Format Specifications
draft-ietf-cellar-matroska-09
The information below is for an old version of the document.
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| Authors | Steve Lhomme, Moritz Bunkus, Dave Rice | ||
| Last updated | 2022-03-29 | ||
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draft-ietf-cellar-matroska-09
cellar S. Lhomme
Internet-Draft
Intended status: Standards Track M. Bunkus
Expires: 30 September 2022
D. Rice
29 March 2022
Matroska Media Container Format Specifications
draft-ietf-cellar-matroska-09
Abstract
This document defines the Matroska audiovisual container, including
definitions of its structural elements, as well as its terminology,
vocabulary, and application.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on 30 September 2022.
Copyright Notice
Copyright (c) 2022 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
extracted from this document must include Revised BSD License text as
described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Revised BSD License.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 6
2. Status of this document . . . . . . . . . . . . . . . . . . . 7
3. Security Considerations . . . . . . . . . . . . . . . . . . . 7
4. Notation and Conventions . . . . . . . . . . . . . . . . . . 7
5. Basis in EBML . . . . . . . . . . . . . . . . . . . . . . . . 8
5.1. Added Constraints on EBML . . . . . . . . . . . . . . . . 8
5.2. Matroska Design . . . . . . . . . . . . . . . . . . . . . 8
6. Language Codes . . . . . . . . . . . . . . . . . . . . . . . 9
7. Matroska Structure . . . . . . . . . . . . . . . . . . . . . 9
8. Matroska Schema . . . . . . . . . . . . . . . . . . . . . . . 18
8.1. Segment Element . . . . . . . . . . . . . . . . . . . . . 18
8.1.1. SeekHead Element . . . . . . . . . . . . . . . . . . 19
8.1.1.1. Seek Element . . . . . . . . . . . . . . . . . . 19
8.1.2. Info Element . . . . . . . . . . . . . . . . . . . . 20
8.1.2.1. SegmentUID Element . . . . . . . . . . . . . . . 20
8.1.2.2. SegmentFilename Element . . . . . . . . . . . . . 21
8.1.2.3. PrevUID Element . . . . . . . . . . . . . . . . . 21
8.1.2.4. PrevFilename Element . . . . . . . . . . . . . . 22
8.1.2.5. NextUID Element . . . . . . . . . . . . . . . . . 22
8.1.2.6. NextFilename Element . . . . . . . . . . . . . . 22
8.1.2.7. SegmentFamily Element . . . . . . . . . . . . . . 23
8.1.2.8. ChapterTranslate Element . . . . . . . . . . . . 23
8.1.2.9. TimestampScale Element . . . . . . . . . . . . . 25
8.1.2.10. Duration Element . . . . . . . . . . . . . . . . 25
8.1.2.11. DateUTC Element . . . . . . . . . . . . . . . . . 26
8.1.2.12. Title Element . . . . . . . . . . . . . . . . . . 26
8.1.2.13. MuxingApp Element . . . . . . . . . . . . . . . . 26
8.1.2.14. WritingApp Element . . . . . . . . . . . . . . . 27
8.1.3. Cluster Element . . . . . . . . . . . . . . . . . . . 27
8.1.3.1. Timestamp Element . . . . . . . . . . . . . . . . 27
8.1.3.2. Position Element . . . . . . . . . . . . . . . . 28
8.1.3.3. PrevSize Element . . . . . . . . . . . . . . . . 28
8.1.3.4. SimpleBlock Element . . . . . . . . . . . . . . . 29
8.1.3.5. BlockGroup Element . . . . . . . . . . . . . . . 29
8.1.4. Tracks Element . . . . . . . . . . . . . . . . . . . 34
8.1.4.1. TrackEntry Element . . . . . . . . . . . . . . . 34
8.1.5. Cues Element . . . . . . . . . . . . . . . . . . . . 96
8.1.5.1. CuePoint Element . . . . . . . . . . . . . . . . 96
8.1.6. Attachments Element . . . . . . . . . . . . . . . . . 100
8.1.6.1. AttachedFile Element . . . . . . . . . . . . . . 101
8.1.7. Chapters Element . . . . . . . . . . . . . . . . . . 103
8.1.7.1. EditionEntry Element . . . . . . . . . . . . . . 103
8.1.8. Tags Element . . . . . . . . . . . . . . . . . . . . 113
8.1.8.1. Tag Element . . . . . . . . . . . . . . . . . . . 114
9. Matroska Element Ordering . . . . . . . . . . . . . . . . . . 121
9.1. Top-Level Elements . . . . . . . . . . . . . . . . . . . 121
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9.2. CRC-32 . . . . . . . . . . . . . . . . . . . . . . . . . 121
9.3. SeekHead . . . . . . . . . . . . . . . . . . . . . . . . 122
9.4. Cues (index) . . . . . . . . . . . . . . . . . . . . . . 122
9.5. Info . . . . . . . . . . . . . . . . . . . . . . . . . . 122
9.6. Chapters Element . . . . . . . . . . . . . . . . . . . . 122
9.7. Attachments . . . . . . . . . . . . . . . . . . . . . . . 123
9.8. Tags . . . . . . . . . . . . . . . . . . . . . . . . . . 123
9.9. Optimum layout from a muxer . . . . . . . . . . . . . . . 123
9.10. Optimum layout after editing tags . . . . . . . . . . . . 123
9.11. Optimum layout with Cues at the front . . . . . . . . . . 124
10. Unknown elements . . . . . . . . . . . . . . . . . . . . . . 124
11. DefaultDecodedFieldDuration . . . . . . . . . . . . . . . . . 125
12. Block Structure . . . . . . . . . . . . . . . . . . . . . . . 125
12.1. Block Header . . . . . . . . . . . . . . . . . . . . . . 126
12.2. Block Header Flags . . . . . . . . . . . . . . . . . . . 126
12.3. SimpleBlock Structure . . . . . . . . . . . . . . . . . 127
12.3.1. SimpleBlock Header . . . . . . . . . . . . . . . . . 127
12.3.2. SimpleBlock Header Flags . . . . . . . . . . . . . . 127
12.4. Block Lacing . . . . . . . . . . . . . . . . . . . . . . 128
12.4.1. No lacing . . . . . . . . . . . . . . . . . . . . . 128
12.4.2. Xiph lacing . . . . . . . . . . . . . . . . . . . . 129
12.4.3. EBML lacing . . . . . . . . . . . . . . . . . . . . 130
12.4.4. Fixed-size lacing . . . . . . . . . . . . . . . . . 132
12.4.5. Laced Frames Timestamp . . . . . . . . . . . . . . . 133
12.5. Random Access Points . . . . . . . . . . . . . . . . . . 133
13. Timestamps . . . . . . . . . . . . . . . . . . . . . . . . . 135
13.1. Timestamp Ticks . . . . . . . . . . . . . . . . . . . . 135
13.1.1. Matroska Ticks . . . . . . . . . . . . . . . . . . . 135
13.1.2. Segment Ticks . . . . . . . . . . . . . . . . . . . 135
13.1.3. Track Ticks . . . . . . . . . . . . . . . . . . . . 136
13.2. Block Timestamps . . . . . . . . . . . . . . . . . . . . 137
13.3. TimestampScale Rounding . . . . . . . . . . . . . . . . 137
14. Encryption . . . . . . . . . . . . . . . . . . . . . . . . . 138
15. Image Presentation . . . . . . . . . . . . . . . . . . . . . 138
15.1. Cropping . . . . . . . . . . . . . . . . . . . . . . . . 138
15.2. Rotation . . . . . . . . . . . . . . . . . . . . . . . . 139
16. Matroska versioning . . . . . . . . . . . . . . . . . . . . . 139
17. File Extensions . . . . . . . . . . . . . . . . . . . . . . . 140
18. Segment Position . . . . . . . . . . . . . . . . . . . . . . 140
18.1. Segment Position Exception . . . . . . . . . . . . . . . 140
18.2. Example of Segment Position . . . . . . . . . . . . . . 140
19. Linked Segments . . . . . . . . . . . . . . . . . . . . . . . 141
19.1. Hard Linking . . . . . . . . . . . . . . . . . . . . . . 141
19.2. Medium Linking . . . . . . . . . . . . . . . . . . . . . 144
19.2.1. Linked-Duration . . . . . . . . . . . . . . . . . . 145
19.2.2. Linked-Edition . . . . . . . . . . . . . . . . . . . 145
20. Track Flags . . . . . . . . . . . . . . . . . . . . . . . . . 145
20.1. Default flag . . . . . . . . . . . . . . . . . . . . . . 145
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20.2. Forced flag . . . . . . . . . . . . . . . . . . . . . . 146
20.3. Hearing-impaired flag . . . . . . . . . . . . . . . . . 146
20.4. Visual-impaired flag . . . . . . . . . . . . . . . . . . 146
20.5. Descriptions flag . . . . . . . . . . . . . . . . . . . 146
20.6. Original flag . . . . . . . . . . . . . . . . . . . . . 146
20.7. Commentary flag . . . . . . . . . . . . . . . . . . . . 146
20.8. Track Operation . . . . . . . . . . . . . . . . . . . . 146
20.9. Overlay Track . . . . . . . . . . . . . . . . . . . . . 147
20.10. Multi-planar and 3D videos . . . . . . . . . . . . . . . 147
21. Default track selection . . . . . . . . . . . . . . . . . . . 148
21.1. Audio Selection . . . . . . . . . . . . . . . . . . . . 148
21.2. Subtitle selection . . . . . . . . . . . . . . . . . . . 150
22. Chapters . . . . . . . . . . . . . . . . . . . . . . . . . . 152
22.1. EditionEntry . . . . . . . . . . . . . . . . . . . . . . 152
22.1.1. EditionFlagDefault . . . . . . . . . . . . . . . . . 152
22.1.2. Default Edition . . . . . . . . . . . . . . . . . . 152
22.1.3. EditionFlagOrdered . . . . . . . . . . . . . . . . . 153
22.1.3.1. Ordered-Edition and Matroska Segment-Linking . . 154
22.2. ChapterAtom . . . . . . . . . . . . . . . . . . . . . . 155
22.2.1. ChapterTimeStart . . . . . . . . . . . . . . . . . . 155
22.2.2. ChapterTimeEnd . . . . . . . . . . . . . . . . . . . 155
22.2.3. Nested Chapters . . . . . . . . . . . . . . . . . . 155
22.2.4. Nested Chapters in Ordered Chapters . . . . . . . . 156
22.2.5. ChapterFlagHidden . . . . . . . . . . . . . . . . . 156
22.3. Menu features . . . . . . . . . . . . . . . . . . . . . 157
22.4. Physical Types . . . . . . . . . . . . . . . . . . . . . 157
22.5. Chapter Examples . . . . . . . . . . . . . . . . . . . . 158
22.5.1. Example 1 : basic chaptering . . . . . . . . . . . . 158
22.5.2. Example 2 : nested chapters . . . . . . . . . . . . 160
22.5.2.1. The Micronauts "Bleep To Bleep" . . . . . . . . 160
23. Attachments . . . . . . . . . . . . . . . . . . . . . . . . . 162
23.1. Cover Art . . . . . . . . . . . . . . . . . . . . . . . 163
23.2. Font files . . . . . . . . . . . . . . . . . . . . . . . 164
23.3. They MAY use the MIME types found in older files when
compatibility with older players is necessary. . . . . . 165
23.4. title: Cues . . . . . . . . . . . . . . . . . . . . . . 165
24. Cues . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166
24.1. Recommendations . . . . . . . . . . . . . . . . . . . . 166
25. Matroska Streaming . . . . . . . . . . . . . . . . . . . . . 167
25.1. File Access . . . . . . . . . . . . . . . . . . . . . . 167
25.2. Livestreaming . . . . . . . . . . . . . . . . . . . . . 167
26. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 168
26.1. Matroska Element IDs Registry . . . . . . . . . . . . . 168
26.2. Chapter Codec IDs Registry . . . . . . . . . . . . . . . 185
26.3. MIME Types . . . . . . . . . . . . . . . . . . . . . . . 186
27. Annex A: Historic Deprecated Elements . . . . . . . . . . . . 186
27.1. SilentTracks Element . . . . . . . . . . . . . . . . . . 186
27.2. SilentTrackNumber Element . . . . . . . . . . . . . . . 187
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27.3. BlockVirtual Element . . . . . . . . . . . . . . . . . . 187
27.4. ReferenceVirtual Element . . . . . . . . . . . . . . . . 187
27.5. Slices Element . . . . . . . . . . . . . . . . . . . . . 187
27.6. TimeSlice Element . . . . . . . . . . . . . . . . . . . 188
27.7. LaceNumber Element . . . . . . . . . . . . . . . . . . . 188
27.8. FrameNumber Element . . . . . . . . . . . . . . . . . . 188
27.9. BlockAdditionID Element . . . . . . . . . . . . . . . . 188
27.10. Delay Element . . . . . . . . . . . . . . . . . . . . . 189
27.11. SliceDuration Element . . . . . . . . . . . . . . . . . 189
27.12. ReferenceFrame Element . . . . . . . . . . . . . . . . . 189
27.13. ReferenceOffset Element . . . . . . . . . . . . . . . . 189
27.14. ReferenceTimestamp Element . . . . . . . . . . . . . . . 190
27.15. EncryptedBlock Element . . . . . . . . . . . . . . . . . 190
27.16. TrackOffset Element . . . . . . . . . . . . . . . . . . 190
27.17. CodecSettings Element . . . . . . . . . . . . . . . . . 190
27.18. CodecInfoURL Element . . . . . . . . . . . . . . . . . . 191
27.19. CodecDownloadURL Element . . . . . . . . . . . . . . . . 191
27.20. CodecDecodeAll Element . . . . . . . . . . . . . . . . . 191
27.21. OldStereoMode Element . . . . . . . . . . . . . . . . . 191
27.22. AspectRatioType Element . . . . . . . . . . . . . . . . 191
27.23. GammaValue Element . . . . . . . . . . . . . . . . . . . 192
27.24. FrameRate Element . . . . . . . . . . . . . . . . . . . 192
27.25. ChannelPositions Element . . . . . . . . . . . . . . . . 192
27.26. TrickTrackUID Element . . . . . . . . . . . . . . . . . 192
27.27. TrickTrackSegmentUID Element . . . . . . . . . . . . . . 193
27.28. TrickTrackFlag Element . . . . . . . . . . . . . . . . . 193
27.29. TrickMasterTrackUID Element . . . . . . . . . . . . . . 193
27.30. TrickMasterTrackSegmentUID Element . . . . . . . . . . . 193
27.31. ContentSignature Element . . . . . . . . . . . . . . . . 194
27.32. ContentSigKeyID Element . . . . . . . . . . . . . . . . 194
27.33. ContentSigAlgo Element . . . . . . . . . . . . . . . . . 194
27.34. ContentSigHashAlgo Element . . . . . . . . . . . . . . . 194
27.35. CueRefCluster Element . . . . . . . . . . . . . . . . . 195
27.36. CueRefNumber Element . . . . . . . . . . . . . . . . . . 195
27.37. CueRefCodecState Element . . . . . . . . . . . . . . . . 195
27.38. FileReferral Element . . . . . . . . . . . . . . . . . . 195
27.39. FileUsedStartTime Element . . . . . . . . . . . . . . . 196
27.40. FileUsedEndTime Element . . . . . . . . . . . . . . . . 196
27.41. TagDefaultBogus Element . . . . . . . . . . . . . . . . 196
28. Normative References . . . . . . . . . . . . . . . . . . . . 196
29. Informative References . . . . . . . . . . . . . . . . . . . 199
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 200
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1. Introduction
Matroska aims to become THE standard of multimedia container formats.
It was derived from a project called [MCF], but differentiates from
it significantly because it is based on EBML (Extensible Binary Meta
Language) [RFC8794], a binary derivative of XML. EBML enables
significant advantages in terms of future format extensibility,
without breaking file support in old parsers.
First, it is essential to clarify exactly "What an Audio/Video
container is", to avoid any misunderstandings:
* It is NOT a video or audio compression format (codec)
* It is an envelope for which there can be many audio, video, and
subtitles streams, allowing the user to store a complete movie or
CD in a single file.
Matroska is designed with the future in mind. It incorporates
features like:
* Fast seeking in the file
* Chapter entries
* Full metadata (tags) support
* Selectable subtitle/audio/video streams
* Modularly expandable
* Error resilience (can recover playback even when the stream is
damaged)
* Streamable over the internet and local networks (HTTP, CIFS, FTP,
etc)
* Menus (like DVDs have)
Matroska is an open standards project. This means for personal use
it is absolutely free to use and that the technical specifications
describing the bitstream are open to everybody, even to companies
that would like to support it in their products.
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2. Status of this document
This document is a work-in-progress specification defining the
Matroska file format as part of the IETF Cellar working group
(https://datatracker.ietf.org/wg/cellar/charter/). But since it's
quite complete it is used as a reference for the development of
libmatroska.
Note that versions 1, 2, and 3 have been finalized. Version 4 is
currently work in progress. There MAY be further additions to v4.
3. Security Considerations
Matroska inherits security considerations from EBML.
Attacks on a Matroska Reader could include:
* Storage of a arbitrary and potentially executable data within an
Attachment Element. Matroska Readers that extract or use data
from Matroska Attachments SHOULD check that the data adheres to
expectations.
* A Matroska Attachment with an inaccurate mime-type.
4. Notation and Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
This document defines specific terms in order to define the format
and application of Matroska. Specific terms are defined below:
Matroska: A multimedia container format based on EBML (Extensible
Binary Meta Language).
Matroska Reader: A data parser that interprets the semantics of a
Matroska document and creates a way for programs to use Matroska.
Matroska Player: A Matroska Reader with a primary purpose of playing
audiovisual files, including Matroska documents.
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5. Basis in EBML
Matroska is a Document Type of EBML (Extensible Binary Meta
Language). This specification is dependent on the EBML Specification
[RFC8794]. For an understanding of Matroska's EBML Schema, see in
particular the sections of the EBML Specification covering EBML
Element Types (Section 7), EBML Schema (Section 11.1), and EBML
Structure (Section 3).
5.1. Added Constraints on EBML
As an EBML Document Type, Matroska adds the following constraints to
the EBML specification.
* The docType of the EBML Header MUST be "matroska".
* The EBMLMaxIDLength of the EBML Header MUST be "4".
* The EBMLMaxSizeLength of the EBML Header MUST be between "1" and
"8" inclusive.
5.2. Matroska Design
The Root Element and all Top-Levels Elements use 4 octets for their
EBML Element ID -- i.e. Segment and direct children of Segment.
Legacy EBML/Matroska parsers did not handle Empty Elements properly,
elements present in the file but with a length of zero. They always
assumed the value was 0 for integers/dates and 0x0p+0 for floats, no
matter the default value of the element which should have been used
instead. Therefore Matroska writers MUST NOT use EBML Empty
Elements, if the element has a default value that is not 0 for
integers/dates and 0x0p+0 for floats.
When adding new elements to Matroska, these rules MUST be followed:
* A non-mandatory integer/date Element MUST NOT have a default value
other than 0.
* A non-mandatory float Element MUST NOT have a default value other
than 0x0p+0.
* A non-mandatory string Element MUST NOT have a default value, as
empty string cannot be defined in the XML Schema.
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6. Language Codes
Matroska from version 1 through 3 uses language codes that can be
either the 3 letters bibliographic ISO-639-2 form [ISO639-2] (like
"fre" for french), or such a language code followed by a dash and a
country code for specialities in languages (like "fre-ca" for
Canadian French). The ISO 639-2 Language Elements are "Language
Element", "TagLanguage Element", and "ChapLanguage Element".
Starting in Matroska version 4, either [ISO639-2] or [BCP47] MAY be
used, although BCP 47 is RECOMMENDED. The BCP 47 Language Elements
are "LanguageIETF Element", "TagLanguageIETF Element", and
"ChapLanguageIETF Element". If a BCP 47 Language Element and an ISO
639-2 Language Element are used within the same Parent Element, then
the ISO 639-2 Language Element MUST be ignored and precedence given
to the BCP 47 Language Element.
Country codes are the same 2 octets country-codes as in Internet
domains [IANADomains] based on [ISO3166-1] alpha-2 codes.
7. Matroska Structure
A Matroska file MUST be composed of at least one EBML Document using
the Matroska Document Type. Each EBML Document MUST start with an
EBML Header and MUST be followed by the EBML Root Element, defined as
Segment in Matroska. Matroska defines several Top Level Elements
which MAY occur within the Segment.
As an example, a simple Matroska file consisting of a single EBML
Document could be represented like this:
* EBML Header
* Segment
A more complex Matroska file consisting of an EBML Stream (consisting
of two EBML Documents) could be represented like this:
* EBML Header
* Segment
* EBML Header
* Segment
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The following diagram represents a simple Matroska file, comprised of
an EBML Document with an EBML Header, a Segment Element (the Root
Element), and all eight Matroska Top Level Elements. In the
following diagrams of this section, horizontal spacing expresses a
parent-child relationship between Matroska Elements (e.g., the Info
Element is contained within the Segment Element) whereas vertical
alignment represents the storage order within the file.
+-------------+
| EBML Header |
+---------------------------+
| Segment | SeekHead |
| |-------------|
| | Info |
| |-------------|
| | Tracks |
| |-------------|
| | Chapters |
| |-------------|
| | Cluster |
| |-------------|
| | Cues |
| |-------------|
| | Attachments |
| |-------------|
| | Tags |
+---------------------------+
Figure 1: Basic layout of a Matroska file.
The Matroska EBML Schema defines eight Top Level Elements: SeekHead,
Info, Tracks, Chapters, Cluster, Cues, Attachments, and Tags.
The SeekHead Element (also known as MetaSeek) contains an index of
Top Level Elements locations within the Segment. Use of the SeekHead
Element is RECOMMENDED. Without a SeekHead Element, a Matroska
parser would have to search the entire file to find all of the other
Top Level Elements. This is due to Matroska's flexible ordering
requirements; for instance, it is acceptable for the Chapters Element
to be stored after the Cluster Elements.
+--------------------------------+
| SeekHead | Seek | SeekID |
| | |--------------|
| | | SeekPosition |
+--------------------------------+
Figure 2: Representation of a SeekHead Element.
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The Info Element contains vital information for identifying the whole
Segment. This includes the title for the Segment, a randomly
generated unique identifier, and the unique identifier(s) of any
linked Segment Elements.
+-------------------------+
| Info | SegmentUID |
| |------------------|
| | SegmentFilename |
| |------------------|
| | PrevUID |
| |------------------|
| | PrevFilename |
| |------------------|
| | NextUID |
| |------------------|
| | NextFilename |
| |------------------|
| | SegmentFamily |
| |------------------|
| | ChapterTranslate |
| |------------------|
| | TimestampScale |
| |------------------|
| | Duration |
| |------------------|
| | DateUTC |
| |------------------|
| | Title |
| |------------------|
| | MuxingApp |
| |------------------|
| | WritingApp |
|-------------------------|
Figure 3: Representation of an Info Element and its Child Elements.
The Tracks Element defines the technical details for each track and
can store the name, number, unique identifier, language, and type
(audio, video, subtitles, etc.) of each track. For example, the
Tracks Element MAY store information about the resolution of a video
track or sample rate of an audio track.
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The Tracks Element MUST identify all the data needed by the codec to
decode the data of the specified track. However, the data required
is contingent on the codec used for the track. For example, a Track
Element for uncompressed audio only requires the audio bit rate to be
present. A codec such as AC-3 would require that the CodecID Element
be present for all tracks, as it is the primary way to identify which
codec to use to decode the track.
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+------------------------------------+
| Tracks | TrackEntry | TrackNumber |
| | |--------------|
| | | TrackUID |
| | |--------------|
| | | TrackType |
| | |--------------|
| | | Name |
| | |--------------|
| | | Language |
| | |--------------|
| | | CodecID |
| | |--------------|
| | | CodecPrivate |
| | |--------------|
| | | CodecName |
| | |----------------------------------+
| | | Video | FlagInterlaced |
| | | |-------------------|
| | | | FieldOrder |
| | | |-------------------|
| | | | StereoMode |
| | | |-------------------|
| | | | AlphaMode |
| | | |-------------------|
| | | | PixelWidth |
| | | |-------------------|
| | | | PixelHeight |
| | | |-------------------|
| | | | DisplayWidth |
| | | |-------------------|
| | | | DisplayHeight |
| | | |-------------------|
| | | | AspectRatioType |
| | | |-------------------|
| | | | Color |
| | |----------------------------------|
| | | Audio | SamplingFrequency |
| | | |-------------------|
| | | | Channels |
| | | |-------------------|
| | | | BitDepth |
|--------------------------------------------------------|
Figure 4: Representation of the Tracks Element and a selection of its
Descendant Elements.
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The Chapters Element lists all of the chapters. Chapters are a way
to set predefined points to jump to in video or audio.
+-----------------------------------------+
| Chapters | Edition | EditionUID |
| | Entry |--------------------|
| | | EditionFlagDefault |
| | |--------------------|
| | | EditionFlagOrdered |
| | |---------------------------------+
| | | ChapterAtom | ChapterUID |
| | | |-------------------|
| | | | ChapterStringUID |
| | | |-------------------|
| | | | ChapterTimeStart |
| | | |-------------------|
| | | | ChapterTimeEnd |
| | | |-------------------|
| | | | ChapterFlagHidden |
| | | |-------------------------------+
| | | | ChapterDisplay | ChapString |
| | | | |--------------|
| | | | | ChapLanguage |
+------------------------------------------------------------------+
Figure 5: Representation of the Chapters Element and a selection
of its Descendant Elements.
Cluster Elements contain the content for each track, e.g., video
frames. A Matroska file SHOULD contain at least one Cluster Element.
The Cluster Element helps to break up SimpleBlock or BlockGroup
Elements and helps with seeking and error protection. It is
RECOMMENDED that the size of each individual Cluster Element be
limited to store no more than 5 seconds or 5 megabytes. Every
Cluster Element MUST contain a Timestamp Element. This SHOULD be the
Timestamp Element used to play the first Block in the Cluster
Element. There SHOULD be one or more BlockGroup or SimpleBlock
Element in each Cluster Element. A BlockGroup Element MAY contain a
Block of data and any information relating directly to that Block.
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+--------------------------+
| Cluster | Timestamp |
| |----------------|
| | SilentTracks |
| |----------------|
| | Position |
| |----------------|
| | PrevSize |
| |----------------|
| | SimpleBlock |
| |----------------|
| | BlockGroup |
+--------------------------+
Figure 6: Representation of a Cluster Element and its immediate
Child Elements.
+----------------------------------+
| Block | Portion of | Data Type |
| | a Block | - Bit Flag |
| |--------------------------+
| | Header | TrackNumber |
| | |-------------|
| | | Timestamp |
| | |-------------|
| | | Flags |
| | | - Gap |
| | | - Lacing |
| | | - Reserved |
| |--------------------------|
| | Optional | FrameSize |
| |--------------------------|
| | Data | Frame |
+----------------------------------+
Figure 7: Representation of the Block Element structure.
Each Cluster MUST contain exactly one Timestamp Element. The
Timestamp Element value MUST be stored once per Cluster. The
Timestamp Element in the Cluster is relative to the entire Segment.
The Timestamp Element SHOULD be the first Element in the Cluster.
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Additionally, the Block contains an offset that, when added to the
Cluster's Timestamp Element value, yields the Block's effective
timestamp. Therefore, timestamp in the Block itself is relative to
the Timestamp Element in the Cluster. For example, if the Timestamp
Element in the Cluster is set to 10 seconds and a Block in that
Cluster is supposed to be played 12 seconds into the clip, the
timestamp in the Block would be set to 2 seconds.
The ReferenceBlock in the BlockGroup is used instead of the basic
"P-frame"/"B-frame" description. Instead of simply saying that this
Block depends on the Block directly before, or directly afterwards,
the Timestamp of the necessary Block is used. Because there can be
as many ReferenceBlock Elements as necessary for a Block, it allows
for some extremely complex referencing.
The Cues Element is used to seek when playing back a file by
providing a temporal index for some of the Tracks. It is similar to
the SeekHead Element, but used for seeking to a specific time when
playing back the file. It is possible to seek without this element,
but it is much more difficult because a Matroska Reader would have to
'hunt and peck' through the file looking for the correct timestamp.
The Cues Element SHOULD contain at least one CuePoint Element. Each
CuePoint Element stores the position of the Cluster that contains the
BlockGroup or SimpleBlock Element. The timestamp is stored in the
CueTime Element and location is stored in the CueTrackPositions
Element.
The Cues Element is flexible. For instance, Cues Element can be used
to index every single timestamp of every Block or they can be indexed
selectively. For video files, it is RECOMMENDED to index at least
the keyframes of the video track.
+-------------------------------------+
| Cues | CuePoint | CueTime |
| | |-------------------|
| | | CueTrackPositions |
| |------------------------------|
| | CuePoint | CueTime |
| | |-------------------|
| | | CueTrackPositions |
+-------------------------------------+
Figure 8: Representation of a Cues Element and two levels of its
Descendant Elements.
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The Attachments Element is for attaching files to a Matroska file
such as pictures, webpages, programs, or even the codec needed to
play back the file.
+------------------------------------------------+
| Attachments | AttachedFile | FileDescription |
| | |-------------------|
| | | FileName |
| | |-------------------|
| | | FileMimeType |
| | |-------------------|
| | | FileData |
| | |-------------------|
| | | FileUID |
| | |-------------------|
| | | FileName |
| | |-------------------|
| | | FileReferral |
| | |-------------------|
| | | FileUsedStartTime |
| | |-------------------|
| | | FileUsedEndTime |
+------------------------------------------------+
Figure 9: Representation of a Attachments Element.
The Tags Element contains metadata that describes the Segment and
potentially its Tracks, Chapters, and Attachments. Each Track or
Chapter that those tags applies to has its UID listed in the Tags.
The Tags contain all extra information about the file: scriptwriter,
singer, actors, directors, titles, edition, price, dates, genre,
comments, etc. Tags can contain their values in multiple languages.
For example, a movie's "title" Tag might contain both the original
English title as well as the title it was released as in Germany.
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+-------------------------------------------+
| Tags | Tag | Targets | TargetTypeValue |
| | | |------------------|
| | | | TargetType |
| | | |------------------|
| | | | TagTrackUID |
| | | |------------------|
| | | | TagEditionUID |
| | | |------------------|
| | | | TagChapterUID |
| | | |------------------|
| | | | TagAttachmentUID |
| | |------------------------------|
| | | SimpleTag | TagName |
| | | |------------------|
| | | | TagLanguage |
| | | |------------------|
| | | | TagDefault |
| | | |------------------|
| | | | TagString |
| | | |------------------|
| | | | TagBinary |
| | | |------------------|
| | | | SimpleTag |
+-------------------------------------------+
Figure 10: Representation of a Tags Element and three levels of
its Children Elements.
8. Matroska Schema
This specification includes an EBML Schema, which defines the
Elements and structure of Matroska as an EBML Document Type. The
EBML Schema defines every valid Matroska element in a manner defined
by the EBML specification.
Here the definition of each Matroska Element is provided.
8.1. Segment Element
name: Segment
path: \Segment
id: 0x18538067
minOccurs: 1
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maxOccurs: 1
type: master
unknownsizeallowed: 1
definition: The Root Element that contains all other Top-Level
Elements (Elements defined only at Level 1). A Matroska file is
composed of 1 Segment.
8.1.1. SeekHead Element
name: SeekHead
path: \Segment\SeekHead
id: 0x114D9B74
maxOccurs: 2
type: master
definition: Contains the Segment Position of other Top-Level
Elements.
8.1.1.1. Seek Element
name: Seek
path: \Segment\SeekHead\Seek
id: 0x4DBB
minOccurs: 1
type: master
definition: Contains a single seek entry to an EBML Element.
8.1.1.1.1. SeekID Element
name: SeekID
path: \Segment\SeekHead\Seek\SeekID
id: 0x53AB
minOccurs: 1
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maxOccurs: 1
type: binary
definition: The binary ID corresponding to the Element name.
8.1.1.1.2. SeekPosition Element
name: SeekPosition
path: \Segment\SeekHead\Seek\SeekPosition
id: 0x53AC
minOccurs: 1
maxOccurs: 1
type: uinteger
definition: The Segment Position of the Element.
8.1.2. Info Element
name: Info
path: \Segment\Info
id: 0x1549A966
minOccurs: 1
maxOccurs: 1
type: master
recurring: 1
definition: Contains general information about the Segment.
8.1.2.1. SegmentUID Element
name: SegmentUID
path: \Segment\Info\SegmentUID
id: 0x73A4
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maxOccurs: 1
range: not 0
type: binary
definition: A randomly generated unique ID to identify the Segment
amongst many others (128 bits).
usage notes: If the Segment is a part of a Linked Segment, then this
Element is REQUIRED.
8.1.2.2. SegmentFilename Element
name: SegmentFilename
path: \Segment\Info\SegmentFilename
id: 0x7384
maxOccurs: 1
type: utf-8
definition: A filename corresponding to this Segment.
8.1.2.3. PrevUID Element
name: PrevUID
path: \Segment\Info\PrevUID
id: 0x3CB923
maxOccurs: 1
type: binary
definition: A unique ID to identify the previous Segment of a Linked
Segment (128 bits).
usage notes: If the Segment is a part of a Linked Segment that uses
Hard Linking, then either the PrevUID or the NextUID Element is
REQUIRED. If a Segment contains a PrevUID but not a NextUID, then
it MAY be considered as the last Segment of the Linked Segment.
The PrevUID MUST NOT be equal to the SegmentUID.
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8.1.2.4. PrevFilename Element
name: PrevFilename
path: \Segment\Info\PrevFilename
id: 0x3C83AB
maxOccurs: 1
type: utf-8
definition: A filename corresponding to the file of the previous
Linked Segment.
usage notes: Provision of the previous filename is for display
convenience, but PrevUID SHOULD be considered authoritative for
identifying the previous Segment in a Linked Segment.
8.1.2.5. NextUID Element
name: NextUID
path: \Segment\Info\NextUID
id: 0x3EB923
maxOccurs: 1
type: binary
definition: A unique ID to identify the next Segment of a Linked
Segment (128 bits).
usage notes: If the Segment is a part of a Linked Segment that uses
Hard Linking, then either the PrevUID or the NextUID Element is
REQUIRED. If a Segment contains a NextUID but not a PrevUID, then
it MAY be considered as the first Segment of the Linked Segment.
The NextUID MUST NOT be equal to the SegmentUID.
8.1.2.6. NextFilename Element
name: NextFilename
path: \Segment\Info\NextFilename
id: 0x3E83BB
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maxOccurs: 1
type: utf-8
definition: A filename corresponding to the file of the next Linked
Segment.
usage notes: Provision of the next filename is for display
convenience, but NextUID SHOULD be considered authoritative for
identifying the Next Segment.
8.1.2.7. SegmentFamily Element
name: SegmentFamily
path: \Segment\Info\SegmentFamily
id: 0x4444
type: binary
definition: A randomly generated unique ID that all Segments of a
Linked Segment MUST share (128 bits).
usage notes: If the Segment Info contains a ChapterTranslate
element, this Element is REQUIRED.
8.1.2.8. ChapterTranslate Element
name: ChapterTranslate
path: \Segment\Info\ChapterTranslate
id: 0x6924
type: master
definition: The mapping between this Segment and a segment value in
the given Chapter Codec.
rationale: Chapter Codec may need to address different segments, but
they may not know of the way to identify such segment when stored
in Matroska. This element and its child elements add a way to map
the internal segments known to the Chapter Codec to the Segment
IDs in Matroska. This allows remuxing a file with Chapter Codec
without changing the content of the codec data, just the Segment
mapping.
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8.1.2.8.1. ChapterTranslateID Element
name: ChapterTranslateID
path: \Segment\Info\ChapterTranslate\ChapterTranslateID
id: 0x69A5
minOccurs: 1
maxOccurs: 1
type: binary
definition: The binary value used to represent this Segment in the
chapter codec data. The format depends on the ChapProcessCodecID
used; see Section 8.1.7.1.4.15.
8.1.2.8.2. ChapterTranslateCodec Element
name: ChapterTranslateCodec
path: \Segment\Info\ChapterTranslate\ChapterTranslateCodec
id: 0x69BF
minOccurs: 1
maxOccurs: 1
type: uinteger
definition: This ChapterTranslate applies to this chapter codec of
the given chapter edition(s); see Section 8.1.7.1.4.15.
defined values:
+=======+=================+============================+
| value | label | definition |
+=======+=================+============================+
| 0 | Matroska Script | Chapter commands using the |
| | | Matroska Script codec. |
+-------+-----------------+----------------------------+
| 1 | DVD-menu | Chapter commands using the |
| | | DVD-like codec. |
+-------+-----------------+----------------------------+
Table 1: ChapterTranslateCodec values
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8.1.2.8.3. ChapterTranslateEditionUID Element
name: ChapterTranslateEditionUID
path: \Segment\Info\ChapterTranslate\ChapterTranslateEditionUID
id: 0x69FC
type: uinteger
definition: Specify a chapter edition UID on which this
ChapterTranslate applies.
usage notes: When no ChapterTranslateEditionUID is specified in the
ChapterTranslate, the ChapterTranslate applied to all chapter
editions found in the Segment using the given
ChapterTranslateCodec.
8.1.2.9. TimestampScale Element
name: TimestampScale
path: \Segment\Info\TimestampScale
id: 0x2AD7B1
minOccurs: 1
maxOccurs: 1
range: not 0
default: 1000000
type: uinteger
definition: Base unit for Segment Ticks and Track Ticks, in
nanoseconds. A TimestampScale value of 1.000.000 means scaled
timestamps in the Segment are expressed in milliseconds; see
Section 13 on how to interpret timestamps.
8.1.2.10. Duration Element
name: Duration
path: \Segment\Info\Duration
id: 0x4489
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maxOccurs: 1
range: > 0x0p+0
type: float
definition: Duration of the Segment, expressed in Segment Ticks
which is based on TimestampScale; see Section 13.1.
8.1.2.11. DateUTC Element
name: DateUTC
path: \Segment\Info\DateUTC
id: 0x4461
maxOccurs: 1
type: date
definition: The date and time that the Segment was created by the
muxing application or library.
8.1.2.12. Title Element
name: Title
path: \Segment\Info\Title
id: 0x7BA9
maxOccurs: 1
type: utf-8
definition: General name of the Segment.
8.1.2.13. MuxingApp Element
name: MuxingApp
path: \Segment\Info\MuxingApp
id: 0x4D80
minOccurs: 1
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maxOccurs: 1
type: utf-8
definition: Muxing application or library (example: "libmatroska-
0.4.3").
usage notes: Include the full name of the application or library
followed by the version number.
8.1.2.14. WritingApp Element
name: WritingApp
path: \Segment\Info\WritingApp
id: 0x5741
minOccurs: 1
maxOccurs: 1
type: utf-8
definition: Writing application (example: "mkvmerge-0.3.3").
usage notes: Include the full name of the application followed by
the version number.
8.1.3. Cluster Element
name: Cluster
path: \Segment\Cluster
id: 0x1F43B675
type: master
unknownsizeallowed: 1
definition: The Top-Level Element containing the (monolithic) Block
structure.
8.1.3.1. Timestamp Element
name: Timestamp
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path: \Segment\Cluster\Timestamp
id: 0xE7
minOccurs: 1
maxOccurs: 1
type: uinteger
definition: Absolute timestamp of the cluster, expressed in Segment
Ticks which is based on TimestampScale; see Section 13.1.
usage notes: This element SHOULD be the first child element of the
Cluster it belongs to, or the second if that Cluster contains a
CRC-32 element (Section 9.2).
8.1.3.2. Position Element
name: Position
path: \Segment\Cluster\Position
id: 0xA7
maxOccurs: 1
type: uinteger
definition: The Segment Position of the Cluster in the Segment (0 in
live streams). It might help to resynchronise offset on damaged
streams.
8.1.3.3. PrevSize Element
name: PrevSize
path: \Segment\Cluster\PrevSize
id: 0xAB
maxOccurs: 1
type: uinteger
definition: Size of the previous Cluster, in octets. Can be useful
for backward playing.
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8.1.3.4. SimpleBlock Element
name: SimpleBlock
path: \Segment\Cluster\SimpleBlock
id: 0xA3
type: binary
minver: 2
definition: Similar to Block, see Section 12, but without all the
extra information, mostly used to reduced overhead when no extra
feature is needed; see Section 12.3 on SimpleBlock Structure.
8.1.3.5. BlockGroup Element
name: BlockGroup
path: \Segment\Cluster\BlockGroup
id: 0xA0
type: master
definition: Basic container of information containing a single Block
and information specific to that Block.
8.1.3.5.1. Block Element
name: Block
path: \Segment\Cluster\BlockGroup\Block
id: 0xA1
minOccurs: 1
maxOccurs: 1
type: binary
definition: Block containing the actual data to be rendered and a
timestamp relative to the Cluster Timestamp; see Section 12 on
Block Structure.
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8.1.3.5.2. BlockAdditions Element
name: BlockAdditions
path: \Segment\Cluster\BlockGroup\BlockAdditions
id: 0x75A1
maxOccurs: 1
type: master
definition: Contain additional blocks to complete the main one. An
EBML parser that has no knowledge of the Block structure could
still see and use/skip these data.
8.1.3.5.2.1. BlockMore Element
name: BlockMore
path: \Segment\Cluster\BlockGroup\BlockAdditions\BlockMore
id: 0xA6
minOccurs: 1
type: master
definition: Contain the BlockAdditional and some parameters.
8.1.3.5.2.2. BlockAddID Element
name: BlockAddID
path: \Segment\Cluster\BlockGroup\BlockAdditions\BlockMore\BlockAddI
D
id: 0xEE
minOccurs: 1
maxOccurs: 1
range: not 0
default: 1
type: uinteger
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definition: An ID to identify the BlockAdditional level. If
BlockAddIDType of the corresponding block is 0, this value is also
the value of BlockAddIDType for the meaning of the content of
BlockAdditional.
8.1.3.5.2.3. BlockAdditional Element
name: BlockAdditional
path: \Segment\Cluster\BlockGroup\BlockAdditions\BlockMore\BlockAddi
tional
id: 0xA5
minOccurs: 1
maxOccurs: 1
type: binary
definition: Interpreted by the codec as it wishes (using the
BlockAddID).
8.1.3.5.3. BlockDuration Element
name: BlockDuration
path: \Segment\Cluster\BlockGroup\BlockDuration
id: 0x9B
minOccurs: see implementation notes
maxOccurs: 1
default: see implementation notes
type: uinteger
definition: The duration of the Block, expressed in Track Ticks; see
Section 13.1. The BlockDuration Element can be useful at the end
of a Track to define the duration of the last frame (as there is
no subsequent Block available), or when there is a break in a
track like for subtitle tracks.
notes:
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+===========+===================================================+
| attribute | note |
+===========+===================================================+
| minOccurs | BlockDuration MUST be set (minOccurs=1) if the |
| | associated TrackEntry stores a DefaultDuration |
| | value. |
+-----------+---------------------------------------------------+
| default | When not written and with no DefaultDuration, the |
| | value is assumed to be the difference between the |
| | timestampof this Block and the timestamp of the |
| | next Block in "display" order (not coding order). |
+-----------+---------------------------------------------------+
Table 2: BlockDuration implementation notes
8.1.3.5.4. ReferencePriority Element
name: ReferencePriority
path: \Segment\Cluster\BlockGroup\ReferencePriority
id: 0xFA
minOccurs: 1
maxOccurs: 1
default: 0
type: uinteger
definition: This frame is referenced and has the specified cache
priority. In cache only a frame of the same or higher priority
can replace this frame. A value of 0 means the frame is not
referenced.
8.1.3.5.5. ReferenceBlock Element
name: ReferenceBlock
path: \Segment\Cluster\BlockGroup\ReferenceBlock
id: 0xFB
type: integer
definition: A timestamp value, relative to the timestamp of the
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Block in this BlockGroup, expressed in Track Ticks; see
Section 13.1. This is used to reference other frames necessary to
decode this frame. The relative value SHOULD correspond to a
valid Block this Block depends on. Historically Matroska Writer
didn't write the actual Block(s) this Block depends on, but _some_
Block in the past.
The value "0" MAY also be used to signify this Block cannot be
decoded on its own, but without knownledge of which Block is
necessary. In this case, other ReferenceBlock MUST NOT be found in
the same BlockGroup.
If the BlockGroup doesn't have any ReferenceBlock element, then the
Block it contains can be decoded without using any other Block data.
8.1.3.5.6. CodecState Element
name: CodecState
path: \Segment\Cluster\BlockGroup\CodecState
id: 0xA4
maxOccurs: 1
type: binary
minver: 2
definition: The new codec state to use. Data interpretation is
private to the codec. This information SHOULD always be
referenced by a seek entry.
8.1.3.5.7. DiscardPadding Element
name: DiscardPadding
path: \Segment\Cluster\BlockGroup\DiscardPadding
id: 0x75A2
maxOccurs: 1
type: integer
minver: 4
definition: Duration of the silent data added to the Block,
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expressed in Matroska Ticks -- ie in nanoseconds; see Section 13.1
(padding at the end of the Block for positive value, at the
beginning of the Block for negative value). The duration of
DiscardPadding is not calculated in the duration of the TrackEntry
and SHOULD be discarded during playback.
8.1.4. Tracks Element
name: Tracks
path: \Segment\Tracks
id: 0x1654AE6B
maxOccurs: 1
type: master
recurring: 1
definition: A Top-Level Element of information with many tracks
described.
8.1.4.1. TrackEntry Element
name: TrackEntry
path: \Segment\Tracks\TrackEntry
id: 0xAE
minOccurs: 1
type: master
definition: Describes a track with all Elements.
8.1.4.1.1. TrackNumber Element
name: TrackNumber
path: \Segment\Tracks\TrackEntry\TrackNumber
id: 0xD7
minOccurs: 1
maxOccurs: 1
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range: not 0
type: uinteger
definition: The track number as used in the Block Header (using more
than 127 tracks is not encouraged, though the design allows an
unlimited number).
8.1.4.1.2. TrackUID Element
name: TrackUID
path: \Segment\Tracks\TrackEntry\TrackUID
id: 0x73C5
minOccurs: 1
maxOccurs: 1
range: not 0
type: uinteger
definition: A unique ID to identify the Track.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.3. TrackType Element
name: TrackType
path: \Segment\Tracks\TrackEntry\TrackType
id: 0x83
minOccurs: 1
maxOccurs: 1
type: uinteger
definition: The TrackType defines the type of each frame found in
the Track. The value SHOULD be stored on 1 octet.
defined values:
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+=======+==========+==========================================+
| value | label | each frame contains |
+=======+==========+==========================================+
| 1 | video | An image. |
+-------+----------+------------------------------------------+
| 2 | audio | Audio samples. |
+-------+----------+------------------------------------------+
| 3 | complex | A mix of different other TrackType. The |
| | | codec needs to define how the Matroska |
| | | Player should interpret such data. |
+-------+----------+------------------------------------------+
| 16 | logo | An image to be rendered over the video |
| | | track(s). |
+-------+----------+------------------------------------------+
| 17 | subtitle | Subtitle or closed caption data to be |
| | | rendered over the video track(s). |
+-------+----------+------------------------------------------+
| 18 | buttons | Interactive button(s) to be rendered |
| | | over the video track(s). |
+-------+----------+------------------------------------------+
| 32 | control | Metadata used to control the player of |
| | | the Matroska Player. |
+-------+----------+------------------------------------------+
| 33 | metadata | Timed metadata that can be passed on to |
| | | the Matroska Player. |
+-------+----------+------------------------------------------+
Table 3: TrackType values
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.4. FlagEnabled Element
name: FlagEnabled
path: \Segment\Tracks\TrackEntry\FlagEnabled
id: 0xB9
minOccurs: 1
maxOccurs: 1
range: 0-1
default: 1
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type: uinteger
minver: 2
definition: Set to 1 if the track is usable. It is possible to turn
a not usable track into a usable track using chapter codecs or
control tracks.
8.1.4.1.5. FlagDefault Element
name: FlagDefault
path: \Segment\Tracks\TrackEntry\FlagDefault
id: 0x88
minOccurs: 1
maxOccurs: 1
range: 0-1
default: 1
type: uinteger
definition: Set if that track (audio, video or subs) SHOULD be
eligible for automatic selection by the player; see Section 21 for
more details.
8.1.4.1.6. FlagForced Element
name: FlagForced
path: \Segment\Tracks\TrackEntry\FlagForced
id: 0x55AA
minOccurs: 1
maxOccurs: 1
range: 0-1
default: 0
type: uinteger
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definition: Applies only to subtitles. Set if that track SHOULD be
eligible for automatic selection by the player if it matches the
user's language preference, even if the user's preferences would
normally not enable subtitles with the selected audio track; this
can be used for tracks containing only translations of foreign-
language audio or onscreen text. See Section 21 for more details.
8.1.4.1.7. FlagHearingImpaired Element
name: FlagHearingImpaired
path: \Segment\Tracks\TrackEntry\FlagHearingImpaired
id: 0x55AB
maxOccurs: 1
range: 0-1
type: uinteger
minver: 4
definition: Set to 1 if that track is suitable for users with
hearing impairments, set to 0 if it is unsuitable for users with
hearing impairments.
8.1.4.1.8. FlagVisualImpaired Element
name: FlagVisualImpaired
path: \Segment\Tracks\TrackEntry\FlagVisualImpaired
id: 0x55AC
maxOccurs: 1
range: 0-1
type: uinteger
minver: 4
definition: Set to 1 if that track is suitable for users with visual
impairments, set to 0 if it is unsuitable for users with visual
impairments.
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8.1.4.1.9. FlagTextDescriptions Element
name: FlagTextDescriptions
path: \Segment\Tracks\TrackEntry\FlagTextDescriptions
id: 0x55AD
maxOccurs: 1
range: 0-1
type: uinteger
minver: 4
definition: Set to 1 if that track contains textual descriptions of
video content, set to 0 if that track does not contain textual
descriptions of video content.
8.1.4.1.10. FlagOriginal Element
name: FlagOriginal
path: \Segment\Tracks\TrackEntry\FlagOriginal
id: 0x55AE
maxOccurs: 1
range: 0-1
type: uinteger
minver: 4
definition: Set to 1 if that track is in the content's original
language, set to 0 if it is a translation.
8.1.4.1.11. FlagCommentary Element
name: FlagCommentary
path: \Segment\Tracks\TrackEntry\FlagCommentary
id: 0x55AF
maxOccurs: 1
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range: 0-1
type: uinteger
minver: 4
definition: Set to 1 if that track contains commentary, set to 0 if
it does not contain commentary.
8.1.4.1.12. FlagLacing Element
name: FlagLacing
path: \Segment\Tracks\TrackEntry\FlagLacing
id: 0x9C
minOccurs: 1
maxOccurs: 1
range: 0-1
default: 1
type: uinteger
definition: Set to 1 if the track MAY contain blocks using lacing.
When set to 0 all blocks MUST have their lacing flags set to No
lacing; see Section 12.4 on Block Lacing.
8.1.4.1.13. MinCache Element
name: MinCache
path: \Segment\Tracks\TrackEntry\MinCache
id: 0x6DE7
minOccurs: 1
maxOccurs: 1
default: 0
type: uinteger
definition: The minimum number of frames a player SHOULD be able to
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cache during playback. If set to 0, the reference pseudo-cache
system is not used.
8.1.4.1.14. MaxCache Element
name: MaxCache
path: \Segment\Tracks\TrackEntry\MaxCache
id: 0x6DF8
maxOccurs: 1
type: uinteger
definition: The maximum cache size necessary to store referenced
frames in and the current frame. 0 means no cache is needed.
8.1.4.1.15. DefaultDuration Element
name: DefaultDuration
path: \Segment\Tracks\TrackEntry\DefaultDuration
id: 0x23E383
maxOccurs: 1
range: not 0
type: uinteger
definition: Number of nanoseconds per frame, expressed in Matroska
Ticks -- ie in nanoseconds; see Section 13.1 (frame in the
Matroska sense -- one Element put into a (Simple)Block).
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.16. DefaultDecodedFieldDuration Element
name: DefaultDecodedFieldDuration
path: \Segment\Tracks\TrackEntry\DefaultDecodedFieldDuration
id: 0x234E7A
maxOccurs: 1
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range: not 0
type: uinteger
minver: 4
definition: The period between two successive fields at the output
of the decoding process, expressed in Matroska Ticks -- ie in
nanoseconds; see Section 13.1. see Section 11 for more information
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.17. TrackTimestampScale Element
name: TrackTimestampScale
path: \Segment\Tracks\TrackEntry\TrackTimestampScale
id: 0x23314F
minOccurs: 1
maxOccurs: 1
range: > 0x0p+0
default: 0x1p+0
type: float
maxver: 3
definition: DEPRECATED, DO NOT USE. The scale to apply on this
track to work at normal speed in relation with other tracks
(mostly used to adjust video speed when the audio length differs).
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.18. MaxBlockAdditionID Element
name: MaxBlockAdditionID
path: \Segment\Tracks\TrackEntry\MaxBlockAdditionID
id: 0x55EE
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minOccurs: 1
maxOccurs: 1
default: 0
type: uinteger
definition: The maximum value of BlockAddID (Section 8.1.3.5.2.2).
A value 0 means there is no BlockAdditions (Section 8.1.3.5.2) for
this track.
8.1.4.1.19. BlockAdditionMapping Element
name: BlockAdditionMapping
path: \Segment\Tracks\TrackEntry\BlockAdditionMapping
id: 0x41E4
type: master
minver: 4
definition: Contains elements that extend the track format, by
adding content either to each frame, with BlockAddID
(Section 8.1.3.5.2.2), or to the track as a whole with
BlockAddIDExtraData.
8.1.4.1.19.1. BlockAddIDValue Element
name: BlockAddIDValue
path: \Segment\Tracks\TrackEntry\BlockAdditionMapping\BlockAddIDValu
e
id: 0x41F0
maxOccurs: 1
range: >=2
type: uinteger
minver: 4
definition: If the track format extension needs content beside
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frames, the value refers to the BlockAddID (Section 8.1.3.5.2.2),
value being described. To keep MaxBlockAdditionID as low as
possible, small values SHOULD be used.
8.1.4.1.19.2. BlockAddIDName Element
name: BlockAddIDName
path: \Segment\Tracks\TrackEntry\BlockAdditionMapping\BlockAddIDName
id: 0x41A4
maxOccurs: 1
type: string
minver: 4
definition: A human-friendly name describing the type of
BlockAdditional data, as defined by the associated Block
Additional Mapping.
8.1.4.1.19.3. BlockAddIDType Element
name: BlockAddIDType
path: \Segment\Tracks\TrackEntry\BlockAdditionMapping\BlockAddIDType
id: 0x41E7
minOccurs: 1
maxOccurs: 1
default: 0
type: uinteger
minver: 4
definition: Stores the registered identifier of the Block Additional
Mapping to define how the BlockAdditional data should be handled.
8.1.4.1.19.4. BlockAddIDExtraData Element
name: BlockAddIDExtraData
path: \Segment\Tracks\TrackEntry\BlockAdditionMapping\BlockAddIDExtr
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aData
id: 0x41ED
maxOccurs: 1
type: binary
minver: 4
definition: Extra binary data that the BlockAddIDType can use to
interpret the BlockAdditional data. The interpretation of the
binary data depends on the BlockAddIDType value and the
corresponding Block Additional Mapping.
8.1.4.1.20. Name Element
name: Name
path: \Segment\Tracks\TrackEntry\Name
id: 0x536E
maxOccurs: 1
type: utf-8
definition: A human-readable track name.
8.1.4.1.21. Language Element
name: Language
path: \Segment\Tracks\TrackEntry\Language
id: 0x22B59C
minOccurs: 1
maxOccurs: 1
default: eng
type: string
definition: Specifies the language of the track in the Matroska
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languages form; see Section 6 on language codes. This Element
MUST be ignored if the LanguageIETF Element is used in the same
TrackEntry.
8.1.4.1.22. LanguageIETF Element
name: LanguageIETF
path: \Segment\Tracks\TrackEntry\LanguageIETF
id: 0x22B59D
maxOccurs: 1
type: string
minver: 4
definition: Specifies the language of the track according to [BCP47]
and using the IANA Language Subtag Registry [IANALangRegistry].
If this Element is used, then any Language Elements used in the
same TrackEntry MUST be ignored.
8.1.4.1.23. CodecID Element
name: CodecID
path: \Segment\Tracks\TrackEntry\CodecID
id: 0x86
minOccurs: 1
maxOccurs: 1
type: string
definition: An ID corresponding to the codec, see [MatroskaCodec]
for more info.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.24. CodecPrivate Element
name: CodecPrivate
path: \Segment\Tracks\TrackEntry\CodecPrivate
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id: 0x63A2
maxOccurs: 1
type: binary
definition: Private data only known to the codec.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.25. CodecName Element
name: CodecName
path: \Segment\Tracks\TrackEntry\CodecName
id: 0x258688
maxOccurs: 1
type: utf-8
definition: A human-readable string specifying the codec.
8.1.4.1.26. AttachmentLink Element
name: AttachmentLink
path: \Segment\Tracks\TrackEntry\AttachmentLink
id: 0x7446
maxOccurs: 1
range: not 0
type: uinteger
maxver: 3
definition: The UID of an attachment that is used by this codec.
usage notes: The value MUST match the FileUID value of an attachment
found in this Segment.
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8.1.4.1.27. TrackOverlay Element
name: TrackOverlay
path: \Segment\Tracks\TrackEntry\TrackOverlay
id: 0x6FAB
type: uinteger
definition: Specify that this track is an overlay track for the
Track specified (in the u-integer). That means when this track
has a gap, see Section 27.1 on SilentTracks, the overlay track
SHOULD be used instead. The order of multiple TrackOverlay
matters, the first one is the one that SHOULD be used. If not
found it SHOULD be the second, etc.
8.1.4.1.28. CodecDelay Element
name: CodecDelay
path: \Segment\Tracks\TrackEntry\CodecDelay
id: 0x56AA
minOccurs: 1
maxOccurs: 1
default: 0
type: uinteger
minver: 4
definition: CodecDelay is The codec-built-in delay, expressed in
Matroska Ticks -- ie in nanoseconds; see Section 13.1. It
represents the amount of codec samples that will be discarded by
the decoder during playback. This timestamp value MUST be
subtracted from each frame timestamp in order to get the timestamp
that will be actually played. The value SHOULD be small so the
muxing of tracks with the same actual timestamp are in the same
Cluster.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
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8.1.4.1.29. SeekPreRoll Element
name: SeekPreRoll
path: \Segment\Tracks\TrackEntry\SeekPreRoll
id: 0x56BB
minOccurs: 1
maxOccurs: 1
default: 0
type: uinteger
minver: 4
definition: After a discontinuity, SeekPreRoll is the duration of
the data the decoder MUST decode before the decoded data is valid,
expressed in Matroska Ticks -- ie in nanoseconds; see
Section 13.1.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.30. TrackTranslate Element
name: TrackTranslate
path: \Segment\Tracks\TrackEntry\TrackTranslate
id: 0x6624
type: master
definition: The mapping between this TrackEntry and a track value in
the given Chapter Codec.
rationale: Chapter Codec may need to address content in specific
track, but they may not know of the way to identify tracks in
Matroska. This element and its child elements add a way to map
the internal tracks known to the Chapter Codec to the track IDs in
Matroska. This allows remuxing a file with Chapter Codec without
changing the content of the codec data, just the track mapping.
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8.1.4.1.30.1. TrackTranslateTrackID Element
name: TrackTranslateTrackID
path: \Segment\Tracks\TrackEntry\TrackTranslate\TrackTranslateTrackI
D
id: 0x66A5
minOccurs: 1
maxOccurs: 1
type: binary
definition: The binary value used to represent this TrackEntry in
the chapter codec data. The format depends on the
ChapProcessCodecID used; see Section 8.1.7.1.4.15.
8.1.4.1.30.2. TrackTranslateCodec Element
name: TrackTranslateCodec
path: \Segment\Tracks\TrackEntry\TrackTranslate\TrackTranslateCodec
id: 0x66BF
minOccurs: 1
maxOccurs: 1
type: uinteger
definition: This TrackTranslate applies to this chapter codec of the
given chapter edition(s); see Section 8.1.7.1.4.15.
defined values:
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+=======+=================+============================+
| value | label | definition |
+=======+=================+============================+
| 0 | Matroska Script | Chapter commands using the |
| | | Matroska Script codec. |
+-------+-----------------+----------------------------+
| 1 | DVD-menu | Chapter commands using the |
| | | DVD-like codec. |
+-------+-----------------+----------------------------+
Table 4: TrackTranslateCodec values
8.1.4.1.30.3. TrackTranslateEditionUID Element
name: TrackTranslateEditionUID
path: \Segment\Tracks\TrackEntry\TrackTranslate\TrackTranslateEditio
nUID
id: 0x66FC
type: uinteger
definition: Specify a chapter edition UID on which this
TrackTranslate applies.
usage notes: When no TrackTranslateEditionUID is specified in the
TrackTranslate, the TrackTranslate applies to all chapter editions
found in the Segment using the given TrackTranslateCodec.
8.1.4.1.31. Video Element
name: Video
path: \Segment\Tracks\TrackEntry\Video
id: 0xE0
maxOccurs: 1
type: master
definition: Video settings.
8.1.4.1.31.1. FlagInterlaced Element
name: FlagInterlaced
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path: \Segment\Tracks\TrackEntry\Video\FlagInterlaced
id: 0x9A
minOccurs: 1
maxOccurs: 1
default: 0
type: uinteger
minver: 2
definition: Specify whether the video frames in this track are
interlaced or not.
defined values:
+=======+==============+==========================+
| value | label | definition |
+=======+==============+==========================+
| 0 | undetermined | Unknown status.This |
| | | value SHOULD be avoided. |
+-------+--------------+--------------------------+
| 1 | interlaced | Interlaced frames. |
+-------+--------------+--------------------------+
| 2 | progressive | No interlacing. |
+-------+--------------+--------------------------+
Table 5: FlagInterlaced values
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.2. FieldOrder Element
name: FieldOrder
path: \Segment\Tracks\TrackEntry\Video\FieldOrder
id: 0x9D
minOccurs: 1
maxOccurs: 1
default: 2
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type: uinteger
minver: 4
definition: Specify the field ordering of video frames in this
track.
defined values:
+===============+==============+====================================+
| value | label | definition |
+===============+==============+====================================+
| 0 | progressive | Interlaced frames.This |
| | | value SHOULD be avoided, |
| | | setting FlagInterlaced |
| | | to 2 is sufficient. |
+---------------+--------------+------------------------------------+
| 1 | tff | Top field displayed |
| | | first. Top field stored |
| | | first. |
+---------------+--------------+------------------------------------+
| 2 | undetermined | Unknown field order.This |
| | | value SHOULD be avoided. |
+---------------+--------------+------------------------------------+
| 6 | bff | Bottom field displayed |
| | | first. Bottom field |
| | | stored first. |
+---------------+--------------+------------------------------------+
| 9 | bff(swapped) | Top field displayed |
| | | first. Fields are |
| | | interleaved in storage |
+---------------+--------------+------------------------------------+
| with the top | | |
| line of the | | |
| top field | | |
| stored first. | | |
+---------------+--------------+------------------------------------+
| 14 | tff(swapped) | Bottom field displayed |
| | | first. Fields are |
| | | interleaved in storage |
+---------------+--------------+------------------------------------+
| with the top | | |
| line of the | | |
| top field | | |
| stored first. | | |
+---------------+--------------+------------------------------------+
Table 6: FieldOrder values
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usage notes: If FlagInterlaced is not set to 1, this Element MUST be
ignored.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.3. StereoMode Element
name: StereoMode
path: \Segment\Tracks\TrackEntry\Video\StereoMode
id: 0x53B8
minOccurs: 1
maxOccurs: 1
default: 0
type: uinteger
minver: 3
definition: Stereo-3D video mode. There are some more details in
Section 20.10.
restrictions:
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+=======+===================================================+
| value | label |
+=======+===================================================+
| 0 | mono |
+-------+---------------------------------------------------+
| 1 | side by side (left eye first) |
+-------+---------------------------------------------------+
| 2 | top - bottom (right eye is first) |
+-------+---------------------------------------------------+
| 3 | top - bottom (left eye is first) |
+-------+---------------------------------------------------+
| 4 | checkboard (right eye is first) |
+-------+---------------------------------------------------+
| 5 | checkboard (left eye is first) |
+-------+---------------------------------------------------+
| 6 | row interleaved (right eye is first) |
+-------+---------------------------------------------------+
| 7 | row interleaved (left eye is first) |
+-------+---------------------------------------------------+
| 8 | column interleaved (right eye is first) |
+-------+---------------------------------------------------+
| 9 | column interleaved (left eye is first) |
+-------+---------------------------------------------------+
| 10 | anaglyph (cyan/red) |
+-------+---------------------------------------------------+
| 11 | side by side (right eye first) |
+-------+---------------------------------------------------+
| 12 | anaglyph (green/magenta) |
+-------+---------------------------------------------------+
| 13 | both eyes laced in one Block (left eye is first) |
+-------+---------------------------------------------------+
| 14 | both eyes laced in one Block (right eye is first) |
+-------+---------------------------------------------------+
Table 7: StereoMode values
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.4. AlphaMode Element
name: AlphaMode
path: \Segment\Tracks\TrackEntry\Video\AlphaMode
id: 0x53C0
minOccurs: 1
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maxOccurs: 1
default: 0
type: uinteger
minver: 3
definition: Indicate whether the BlockAdditional Element with
BlockAddID of "1" contains Alpha data, as defined by to the Codec
Mapping for the CodecID. Undefined values SHOULD NOT be used as
the behavior of known implementations is different (considered
either as 0 or 1).
defined values:
+=======+=========+============================================+
| value | label | definition |
+=======+=========+============================================+
| 0 | none | The BlockAdditional Element with |
| | | BlockAddID of "1" does not exist or SHOULD |
| | | NOT be considered as containing such data. |
+-------+---------+--------------------------------------------+
| 1 | present | The BlockAdditional Element with |
| | | BlockAddID of "1" contains alpha channel |
| | | data. |
+-------+---------+--------------------------------------------+
Table 8: AlphaMode values
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.5. PixelWidth Element
name: PixelWidth
path: \Segment\Tracks\TrackEntry\Video\PixelWidth
id: 0xB0
minOccurs: 1
maxOccurs: 1
range: not 0
type: uinteger
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definition: Width of the encoded video frames in pixels.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.6. PixelHeight Element
name: PixelHeight
path: \Segment\Tracks\TrackEntry\Video\PixelHeight
id: 0xBA
minOccurs: 1
maxOccurs: 1
range: not 0
type: uinteger
definition: Height of the encoded video frames in pixels.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.7. PixelCropBottom Element
name: PixelCropBottom
path: \Segment\Tracks\TrackEntry\Video\PixelCropBottom
id: 0x54AA
minOccurs: 1
maxOccurs: 1
default: 0
type: uinteger
definition: The number of video pixels to remove at the bottom of
the image.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
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8.1.4.1.31.8. PixelCropTop Element
name: PixelCropTop
path: \Segment\Tracks\TrackEntry\Video\PixelCropTop
id: 0x54BB
minOccurs: 1
maxOccurs: 1
default: 0
type: uinteger
definition: The number of video pixels to remove at the top of the
image.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.9. PixelCropLeft Element
name: PixelCropLeft
path: \Segment\Tracks\TrackEntry\Video\PixelCropLeft
id: 0x54CC
minOccurs: 1
maxOccurs: 1
default: 0
type: uinteger
definition: The number of video pixels to remove on the left of the
image.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.10. PixelCropRight Element
name: PixelCropRight
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path: \Segment\Tracks\TrackEntry\Video\PixelCropRight
id: 0x54DD
minOccurs: 1
maxOccurs: 1
default: 0
type: uinteger
definition: The number of video pixels to remove on the right of the
image.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.11. DisplayWidth Element
name: DisplayWidth
path: \Segment\Tracks\TrackEntry\Video\DisplayWidth
id: 0x54B0
maxOccurs: 1
range: not 0
default: see implementation notes
type: uinteger
definition: Width of the video frames to display. Applies to the
video frame after cropping (PixelCrop* Elements).
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
notes:
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+===========+=================================================+
| attribute | note |
+===========+=================================================+
| default | If the DisplayUnit of the same TrackEntry is 0, |
| | then the default value for DisplayWidth is |
| | equal toPixelWidth - PixelCropLeft - |
| | PixelCropRight, else there is no default value. |
+-----------+-------------------------------------------------+
Table 9: DisplayWidth implementation notes
8.1.4.1.31.12. DisplayHeight Element
name: DisplayHeight
path: \Segment\Tracks\TrackEntry\Video\DisplayHeight
id: 0x54BA
maxOccurs: 1
range: not 0
default: see implementation notes
type: uinteger
definition: Height of the video frames to display. Applies to the
video frame after cropping (PixelCrop* Elements).
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
notes:
+===========+==================================================+
| attribute | note |
+===========+==================================================+
| default | If the DisplayUnit of the same TrackEntry is 0, |
| | then the default value for DisplayHeight is |
| | equal toPixelHeight - PixelCropTop - |
| | PixelCropBottom, else there is no default value. |
+-----------+--------------------------------------------------+
Table 10: DisplayHeight implementation notes
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8.1.4.1.31.13. DisplayUnit Element
name: DisplayUnit
path: \Segment\Tracks\TrackEntry\Video\DisplayUnit
id: 0x54B2
minOccurs: 1
maxOccurs: 1
default: 0
type: uinteger
definition: How DisplayWidth & DisplayHeight are interpreted.
restrictions:
+=======+======================+
| value | label |
+=======+======================+
| 0 | pixels |
+-------+----------------------+
| 1 | centimeters |
+-------+----------------------+
| 2 | inches |
+-------+----------------------+
| 3 | display aspect ratio |
+-------+----------------------+
| 4 | unknown |
+-------+----------------------+
Table 11: DisplayUnit values
8.1.4.1.31.14. UncompressedFourCC Element
name: UncompressedFourCC
path: \Segment\Tracks\TrackEntry\Video\UncompressedFourCC
id: 0x2EB524
minOccurs: see implementation notes
maxOccurs: 1
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type: binary
definition: Specify the uncompressed pixel format used for the
Track's data as a FourCC. This value is similar in scope to the
biCompression value of AVI's BITMAPINFO [AVIFormat]. See the YUV
video formats [FourCC-YUV] and RGB video formats [FourCC-RGB] for
common values.
usage notes: This Element MUST NOT be used if the CodecID Element of
the TrackEntry is set to "V_UNCOMPRESSED".
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
notes:
+===========+==============================================+
| attribute | note |
+===========+==============================================+
| minOccurs | UncompressedFourCC MUST be set (minOccurs=1) |
| | in TrackEntry, when the CodecID Element of |
| | the TrackEntry is set to "V_UNCOMPRESSED". |
+-----------+----------------------------------------------+
Table 12: UncompressedFourCC implementation notes
8.1.4.1.31.15. Colour Element
name: Colour
path: \Segment\Tracks\TrackEntry\Video\Colour
id: 0x55B0
maxOccurs: 1
type: master
minver: 4
definition: Settings describing the colour format.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
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8.1.4.1.31.16. MatrixCoefficients Element
name: MatrixCoefficients
path: \Segment\Tracks\TrackEntry\Video\Colour\MatrixCoefficients
id: 0x55B1
minOccurs: 1
maxOccurs: 1
default: 2
type: uinteger
minver: 4
definition: The Matrix Coefficients of the video used to derive luma
and chroma values from red, green, and blue color primaries. For
clarity, the value and meanings for MatrixCoefficients are adopted
from Table 4 of ISO/IEC 23001-8:2016 or ITU-T H.273.
restrictions:
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+=======+=======================================+
| value | label |
+=======+=======================================+
| 0 | Identity |
+-------+---------------------------------------+
| 1 | ITU-R BT.709 |
+-------+---------------------------------------+
| 2 | unspecified |
+-------+---------------------------------------+
| 3 | reserved |
+-------+---------------------------------------+
| 4 | US FCC 73.682 |
+-------+---------------------------------------+
| 5 | ITU-R BT.470BG |
+-------+---------------------------------------+
| 6 | SMPTE 170M |
+-------+---------------------------------------+
| 7 | SMPTE 240M |
+-------+---------------------------------------+
| 8 | YCoCg |
+-------+---------------------------------------+
| 9 | BT2020 Non-constant Luminance |
+-------+---------------------------------------+
| 10 | BT2020 Constant Luminance |
+-------+---------------------------------------+
| 11 | SMPTE ST 2085 |
+-------+---------------------------------------+
| 12 | Chroma-derived Non-constant Luminance |
+-------+---------------------------------------+
| 13 | Chroma-derived Constant Luminance |
+-------+---------------------------------------+
| 14 | ITU-R BT.2100-0 |
+-------+---------------------------------------+
Table 13: MatrixCoefficients values
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.17. BitsPerChannel Element
name: BitsPerChannel
path: \Segment\Tracks\TrackEntry\Video\Colour\BitsPerChannel
id: 0x55B2
minOccurs: 1
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maxOccurs: 1
default: 0
type: uinteger
minver: 4
definition: Number of decoded bits per channel. A value of 0
indicates that the BitsPerChannel is unspecified.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.18. ChromaSubsamplingHorz Element
name: ChromaSubsamplingHorz
path: \Segment\Tracks\TrackEntry\Video\Colour\ChromaSubsamplingHorz
id: 0x55B3
maxOccurs: 1
type: uinteger
minver: 4
definition: The amount of pixels to remove in the Cr and Cb channels
for every pixel not removed horizontally. Example: For video with
4:2:0 chroma subsampling, the ChromaSubsamplingHorz SHOULD be set
to 1.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.19. ChromaSubsamplingVert Element
name: ChromaSubsamplingVert
path: \Segment\Tracks\TrackEntry\Video\Colour\ChromaSubsamplingVert
id: 0x55B4
maxOccurs: 1
type: uinteger
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minver: 4
definition: The amount of pixels to remove in the Cr and Cb channels
for every pixel not removed vertically. Example: For video with
4:2:0 chroma subsampling, the ChromaSubsamplingVert SHOULD be set
to 1.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.20. CbSubsamplingHorz Element
name: CbSubsamplingHorz
path: \Segment\Tracks\TrackEntry\Video\Colour\CbSubsamplingHorz
id: 0x55B5
maxOccurs: 1
type: uinteger
minver: 4
definition: The amount of pixels to remove in the Cb channel for
every pixel not removed horizontally. This is additive with
ChromaSubsamplingHorz. Example: For video with 4:2:1 chroma
subsampling, the ChromaSubsamplingHorz SHOULD be set to 1 and
CbSubsamplingHorz SHOULD be set to 1.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.21. CbSubsamplingVert Element
name: CbSubsamplingVert
path: \Segment\Tracks\TrackEntry\Video\Colour\CbSubsamplingVert
id: 0x55B6
maxOccurs: 1
type: uinteger
minver: 4
definition: The amount of pixels to remove in the Cb channel for
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every pixel not removed vertically. This is additive with
ChromaSubsamplingVert.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.22. ChromaSitingHorz Element
name: ChromaSitingHorz
path: \Segment\Tracks\TrackEntry\Video\Colour\ChromaSitingHorz
id: 0x55B7
minOccurs: 1
maxOccurs: 1
default: 0
type: uinteger
minver: 4
definition: How chroma is subsampled horizontally.
restrictions:
+=======+=================+
| value | label |
+=======+=================+
| 0 | unspecified |
+-------+-----------------+
| 1 | left collocated |
+-------+-----------------+
| 2 | half |
+-------+-----------------+
Table 14:
ChromaSitingHorz values
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.23. ChromaSitingVert Element
name: ChromaSitingVert
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path: \Segment\Tracks\TrackEntry\Video\Colour\ChromaSitingVert
id: 0x55B8
minOccurs: 1
maxOccurs: 1
default: 0
type: uinteger
minver: 4
definition: How chroma is subsampled vertically.
restrictions:
+=======+================+
| value | label |
+=======+================+
| 0 | unspecified |
+-------+----------------+
| 1 | top collocated |
+-------+----------------+
| 2 | half |
+-------+----------------+
Table 15:
ChromaSitingVert
values
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.24. Range Element
name: Range
path: \Segment\Tracks\TrackEntry\Video\Colour\Range
id: 0x55B9
minOccurs: 1
maxOccurs: 1
default: 0
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type: uinteger
minver: 4
definition: Clipping of the color ranges.
restrictions:
+=======+=========================================================+
| value | label |
+=======+=========================================================+
| 0 | unspecified |
+-------+---------------------------------------------------------+
| 1 | broadcast range |
+-------+---------------------------------------------------------+
| 2 | full range (no clipping) |
+-------+---------------------------------------------------------+
| 3 | defined by MatrixCoefficients / TransferCharacteristics |
+-------+---------------------------------------------------------+
Table 16: Range values
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.25. TransferCharacteristics Element
name: TransferCharacteristics
path: \Segment\Tracks\TrackEntry\Video\Colour\TransferCharacteristic
s
id: 0x55BA
minOccurs: 1
maxOccurs: 1
default: 2
type: uinteger
minver: 4
definition: The transfer characteristics of the video. For clarity,
the value and meanings for TransferCharacteristics are adopted
from Table 3 of ISO/IEC 23091-4 or ITU-T H.273.
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restrictions:
+=======+=======================================+
| value | label |
+=======+=======================================+
| 0 | reserved |
+-------+---------------------------------------+
| 1 | ITU-R BT.709 |
+-------+---------------------------------------+
| 2 | unspecified |
+-------+---------------------------------------+
| 3 | reserved |
+-------+---------------------------------------+
| 4 | Gamma 2.2 curve - BT.470M |
+-------+---------------------------------------+
| 5 | Gamma 2.8 curve - BT.470BG |
+-------+---------------------------------------+
| 6 | SMPTE 170M |
+-------+---------------------------------------+
| 7 | SMPTE 240M |
+-------+---------------------------------------+
| 8 | Linear |
+-------+---------------------------------------+
| 9 | Log |
+-------+---------------------------------------+
| 10 | Log Sqrt |
+-------+---------------------------------------+
| 11 | IEC 61966-2-4 |
+-------+---------------------------------------+
| 12 | ITU-R BT.1361 Extended Colour Gamut |
+-------+---------------------------------------+
| 13 | IEC 61966-2-1 |
+-------+---------------------------------------+
| 14 | ITU-R BT.2020 10 bit |
+-------+---------------------------------------+
| 15 | ITU-R BT.2020 12 bit |
+-------+---------------------------------------+
| 16 | ITU-R BT.2100 Perceptual Quantization |
+-------+---------------------------------------+
| 17 | SMPTE ST 428-1 |
+-------+---------------------------------------+
| 18 | ARIB STD-B67 (HLG) |
+-------+---------------------------------------+
Table 17: TransferCharacteristics values
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
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8.1.4.1.31.26. Primaries Element
name: Primaries
path: \Segment\Tracks\TrackEntry\Video\Colour\Primaries
id: 0x55BB
minOccurs: 1
maxOccurs: 1
default: 2
type: uinteger
minver: 4
definition: The colour primaries of the video. For clarity, the
value and meanings for Primaries are adopted from Table 2 of ISO/
IEC 23091-4 or ITU-T H.273.
restrictions:
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+=======+========================================+
| value | label |
+=======+========================================+
| 0 | reserved |
+-------+----------------------------------------+
| 1 | ITU-R BT.709 |
+-------+----------------------------------------+
| 2 | unspecified |
+-------+----------------------------------------+
| 3 | reserved |
+-------+----------------------------------------+
| 4 | ITU-R BT.470M |
+-------+----------------------------------------+
| 5 | ITU-R BT.470BG - BT.601 625 |
+-------+----------------------------------------+
| 6 | ITU-R BT.601 525 - SMPTE 170M |
+-------+----------------------------------------+
| 7 | SMPTE 240M |
+-------+----------------------------------------+
| 8 | FILM |
+-------+----------------------------------------+
| 9 | ITU-R BT.2020 |
+-------+----------------------------------------+
| 10 | SMPTE ST 428-1 |
+-------+----------------------------------------+
| 11 | SMPTE RP 432-2 |
+-------+----------------------------------------+
| 12 | SMPTE EG 432-2 |
+-------+----------------------------------------+
| 22 | EBU Tech. 3213-E - JEDEC P22 phosphors |
+-------+----------------------------------------+
Table 18: Primaries values
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.27. MaxCLL Element
name: MaxCLL
path: \Segment\Tracks\TrackEntry\Video\Colour\MaxCLL
id: 0x55BC
maxOccurs: 1
type: uinteger
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minver: 4
definition: Maximum brightness of a single pixel (Maximum Content
Light Level) in candelas per square meter (cd/m^2).
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.28. MaxFALL Element
name: MaxFALL
path: \Segment\Tracks\TrackEntry\Video\Colour\MaxFALL
id: 0x55BD
maxOccurs: 1
type: uinteger
minver: 4
definition: Maximum brightness of a single full frame (Maximum
Frame-Average Light Level) in candelas per square meter (cd/m^2).
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.29. MasteringMetadata Element
name: MasteringMetadata
path: \Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata
id: 0x55D0
maxOccurs: 1
type: master
minver: 4
definition: SMPTE 2086 mastering data.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
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8.1.4.1.31.30. PrimaryRChromaticityX Element
name: PrimaryRChromaticityX
path: \Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\Prim
aryRChromaticityX
id: 0x55D1
maxOccurs: 1
range: 0-1
type: float
minver: 4
definition: Red X chromaticity coordinate, as defined by CIE 1931.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.31. PrimaryRChromaticityY Element
name: PrimaryRChromaticityY
path: \Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\Prim
aryRChromaticityY
id: 0x55D2
maxOccurs: 1
range: 0-1
type: float
minver: 4
definition: Red Y chromaticity coordinate, as defined by CIE 1931.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.32. PrimaryGChromaticityX Element
name: PrimaryGChromaticityX
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path: \Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\Prim
aryGChromaticityX
id: 0x55D3
maxOccurs: 1
range: 0-1
type: float
minver: 4
definition: Green X chromaticity coordinate, as defined by CIE 1931.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.33. PrimaryGChromaticityY Element
name: PrimaryGChromaticityY
path: \Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\Prim
aryGChromaticityY
id: 0x55D4
maxOccurs: 1
range: 0-1
type: float
minver: 4
definition: Green Y chromaticity coordinate, as defined by CIE 1931.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.34. PrimaryBChromaticityX Element
name: PrimaryBChromaticityX
path: \Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\Prim
aryBChromaticityX
id: 0x55D5
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maxOccurs: 1
range: 0-1
type: float
minver: 4
definition: Blue X chromaticity coordinate, as defined by CIE 1931.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.35. PrimaryBChromaticityY Element
name: PrimaryBChromaticityY
path: \Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\Prim
aryBChromaticityY
id: 0x55D6
maxOccurs: 1
range: 0-1
type: float
minver: 4
definition: Blue Y chromaticity coordinate, as defined by CIE 1931.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.36. WhitePointChromaticityX Element
name: WhitePointChromaticityX
path: \Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\Whit
ePointChromaticityX
id: 0x55D7
maxOccurs: 1
range: 0-1
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type: float
minver: 4
definition: White X chromaticity coordinate, as defined by CIE 1931.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.37. WhitePointChromaticityY Element
name: WhitePointChromaticityY
path: \Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\Whit
ePointChromaticityY
id: 0x55D8
maxOccurs: 1
range: 0-1
type: float
minver: 4
definition: White Y chromaticity coordinate, as defined by CIE 1931.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.38. LuminanceMax Element
name: LuminanceMax
path: \Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\Lumi
nanceMax
id: 0x55D9
maxOccurs: 1
range: >= 0x0p+0
type: float
minver: 4
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definition: Maximum luminance. Represented in candelas per square
meter (cd/m^2).
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.39. LuminanceMin Element
name: LuminanceMin
path: \Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\Lumi
nanceMin
id: 0x55DA
maxOccurs: 1
range: >= 0x0p+0
type: float
minver: 4
definition: Minimum luminance. Represented in candelas per square
meter (cd/m^2).
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.40. Projection Element
name: Projection
path: \Segment\Tracks\TrackEntry\Video\Projection
id: 0x7670
maxOccurs: 1
type: master
minver: 4
definition: Describes the video projection details. Used to render
spherical, VR videos or flipping videos horizontally/vertically.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
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8.1.4.1.31.41. ProjectionType Element
name: ProjectionType
path: \Segment\Tracks\TrackEntry\Video\Projection\ProjectionType
id: 0x7671
minOccurs: 1
maxOccurs: 1
default: 0
type: uinteger
minver: 4
definition: Describes the projection used for this video track.
restrictions:
+=======+=================+
| value | label |
+=======+=================+
| 0 | rectangular |
+-------+-----------------+
| 1 | equirectangular |
+-------+-----------------+
| 2 | cubemap |
+-------+-----------------+
| 3 | mesh |
+-------+-----------------+
Table 19:
ProjectionType values
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.42. ProjectionPrivate Element
name: ProjectionPrivate
path: \Segment\Tracks\TrackEntry\Video\Projection\ProjectionPrivate
id: 0x7672
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maxOccurs: 1
type: binary
minver: 4
definition: Private data that only applies to a specific projection.
* If ProjectionType equals 0 (Rectangular), then this element must
not be present.
* If ProjectionType equals 1 (Equirectangular), then this element
must be present and contain the same binary data that would be
stored inside an ISOBMFF Equirectangular Projection Box ('equi').
* If ProjectionType equals 2 (Cubemap), then this element must be
present and contain the same binary data that would be stored
inside an ISOBMFF Cubemap Projection Box ('cbmp').
* If ProjectionType equals 3 (Mesh), then this element must be
present and contain the same binary data that would be stored
inside an ISOBMFF Mesh Projection Box ('mshp').
usage notes: ISOBMFF box size and fourcc fields are not included in
the binary data, but the FullBox version and flag fields are.
This is to avoid redundant framing information while preserving
versioning and semantics between the two container formats.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.43. ProjectionPoseYaw Element
name: ProjectionPoseYaw
path: \Segment\Tracks\TrackEntry\Video\Projection\ProjectionPoseYaw
id: 0x7673
minOccurs: 1
maxOccurs: 1
range: >= -0xB4p+0, <= 0xB4p+0
default: 0x0p+0
type: float
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minver: 4
definition: Specifies a yaw rotation to the projection.
Value represents a clockwise rotation, in degrees, around the up
vector. This rotation must be applied before any ProjectionPosePitch
or ProjectionPoseRoll rotations. The value of this element MUST be
in the -180 to 180 degree range, both included.
Setting ProjectionPoseYaw to 180 or -180 degrees, with the
ProjectionPoseRoll and ProjectionPosePitch set to 0 degrees flips the
image horizontally.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.31.44. ProjectionPosePitch Element
name: ProjectionPosePitch
path: \Segment\Tracks\TrackEntry\Video\Projection\ProjectionPosePitc
h
id: 0x7674
minOccurs: 1
maxOccurs: 1
range: >= -0x5Ap+0, <= 0x5Ap+0
default: 0x0p+0
type: float
minver: 4
definition: Specifies a pitch rotation to the projection.
Value represents a counter-clockwise rotation, in degrees, around the
right vector. This rotation must be applied after the
ProjectionPoseYaw rotation and before the ProjectionPoseRoll
rotation. The value of this element MUST be in the -90 to 90 degree
range, both included.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
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8.1.4.1.31.45. ProjectionPoseRoll Element
name: ProjectionPoseRoll
path: \Segment\Tracks\TrackEntry\Video\Projection\ProjectionPoseRoll
id: 0x7675
minOccurs: 1
maxOccurs: 1
range: >= -0xB4p+0, <= 0xB4p+0
default: 0x0p+0
type: float
minver: 4
definition: Specifies a roll rotation to the projection.
Value represents a counter-clockwise rotation, in degrees, around the
forward vector. This rotation must be applied after the
ProjectionPoseYaw and ProjectionPosePitch rotations. The value of
this element MUST be in the -180 to 180 degree range, both included.
Setting ProjectionPoseRoll to 180 or -180 degrees, the
ProjectionPoseYaw to 180 or -180 degrees with ProjectionPosePitch set
to 0 degrees flips the image vertically.
Setting ProjectionPoseRoll to 180 or -180 degrees, with the
ProjectionPoseYaw and ProjectionPosePitch set to 0 degrees flips the
image horizontally and vertically.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.32. Audio Element
name: Audio
path: \Segment\Tracks\TrackEntry\Audio
id: 0xE1
maxOccurs: 1
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type: master
definition: Audio settings.
8.1.4.1.32.1. SamplingFrequency Element
name: SamplingFrequency
path: \Segment\Tracks\TrackEntry\Audio\SamplingFrequency
id: 0xB5
minOccurs: 1
maxOccurs: 1
range: > 0x0p+0
default: 0x1.f4p+12
type: float
definition: Sampling frequency in Hz.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.32.2. OutputSamplingFrequency Element
name: OutputSamplingFrequency
path: \Segment\Tracks\TrackEntry\Audio\OutputSamplingFrequency
id: 0x78B5
maxOccurs: 1
range: > 0x0p+0
default: see implementation notes
type: float
definition: Real output sampling frequency in Hz (used for SBR
techniques).
notes:
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+===========+======================================================+
| attribute | note |
+===========+======================================================+
| default | The default value for OutputSamplingFrequency of the |
| | same TrackEntry is equal to the SamplingFrequency. |
+-----------+------------------------------------------------------+
Table 20: OutputSamplingFrequency implementation notes
8.1.4.1.32.3. Channels Element
name: Channels
path: \Segment\Tracks\TrackEntry\Audio\Channels
id: 0x9F
minOccurs: 1
maxOccurs: 1
range: not 0
default: 1
type: uinteger
definition: Numbers of channels in the track.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.32.4. BitDepth Element
name: BitDepth
path: \Segment\Tracks\TrackEntry\Audio\BitDepth
id: 0x6264
maxOccurs: 1
range: not 0
type: uinteger
definition: Bits per sample, mostly used for PCM.
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usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.33. TrackOperation Element
name: TrackOperation
path: \Segment\Tracks\TrackEntry\TrackOperation
id: 0xE2
maxOccurs: 1
type: master
minver: 3
definition: Operation that needs to be applied on tracks to create
this virtual track. For more details look at Section 20.8.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.33.1. TrackCombinePlanes Element
name: TrackCombinePlanes
path: \Segment\Tracks\TrackEntry\TrackOperation\TrackCombinePlanes
id: 0xE3
maxOccurs: 1
type: master
minver: 3
definition: Contains the list of all video plane tracks that need to
be combined to create this 3D track
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.33.2. TrackPlane Element
name: TrackPlane
path: \Segment\Tracks\TrackEntry\TrackOperation\TrackCombinePlanes\T
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rackPlane
id: 0xE4
minOccurs: 1
type: master
minver: 3
definition: Contains a video plane track that need to be combined to
create this 3D track
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.33.3. TrackPlaneUID Element
name: TrackPlaneUID
path: \Segment\Tracks\TrackEntry\TrackOperation\TrackCombinePlanes\T
rackPlane\TrackPlaneUID
id: 0xE5
minOccurs: 1
maxOccurs: 1
range: not 0
type: uinteger
minver: 3
definition: The trackUID number of the track representing the plane.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.33.4. TrackPlaneType Element
name: TrackPlaneType
path: \Segment\Tracks\TrackEntry\TrackOperation\TrackCombinePlanes\T
rackPlane\TrackPlaneType
id: 0xE6
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minOccurs: 1
maxOccurs: 1
type: uinteger
minver: 3
definition: The kind of plane this track corresponds to.
restrictions:
+=======+============+
| value | label |
+=======+============+
| 0 | left eye |
+-------+------------+
| 1 | right eye |
+-------+------------+
| 2 | background |
+-------+------------+
Table 21:
TrackPlaneType values
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.33.5. TrackJoinBlocks Element
name: TrackJoinBlocks
path: \Segment\Tracks\TrackEntry\TrackOperation\TrackJoinBlocks
id: 0xE9
maxOccurs: 1
type: master
minver: 3
definition: Contains the list of all tracks whose Blocks need to be
combined to create this virtual track
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
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8.1.4.1.33.6. TrackJoinUID Element
name: TrackJoinUID
path: \Segment\Tracks\TrackEntry\TrackOperation\TrackJoinBlocks\Trac
kJoinUID
id: 0xED
minOccurs: 1
range: not 0
type: uinteger
minver: 3
definition: The trackUID number of a track whose blocks are used to
create this virtual track.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.34. ContentEncodings Element
name: ContentEncodings
path: \Segment\Tracks\TrackEntry\ContentEncodings
id: 0x6D80
maxOccurs: 1
type: master
definition: Settings for several content encoding mechanisms like
compression or encryption.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.34.1. ContentEncoding Element
name: ContentEncoding
path: \Segment\Tracks\TrackEntry\ContentEncodings\ContentEncoding
id: 0x6240
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minOccurs: 1
type: master
definition: Settings for one content encoding like compression or
encryption.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.34.2. ContentEncodingOrder Element
name: ContentEncodingOrder
path: \Segment\Tracks\TrackEntry\ContentEncodings\ContentEncoding\Co
ntentEncodingOrder
id: 0x5031
minOccurs: 1
maxOccurs: 1
default: 0
type: uinteger
definition: Tell in which order to apply each ContentEncoding of the
ContentEncodings. The decoder/demuxer MUST start with the
ContentEncoding with the highest ContentEncodingOrder and work its
way down to the ContentEncoding with the lowest
ContentEncodingOrder. This value MUST be unique over for each
ContentEncoding found in the ContentEncodings of this TrackEntry.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.34.3. ContentEncodingScope Element
name: ContentEncodingScope
path: \Segment\Tracks\TrackEntry\ContentEncodings\ContentEncoding\Co
ntentEncodingScope
id: 0x5032
minOccurs: 1
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maxOccurs: 1
default: 1
type: uinteger
definition: A bit field that describes which Elements have been
modified in this way. Values (big-endian) can be OR'ed.
defined values:
+=======+=========+===================================+
| value | label | definition |
+=======+=========+===================================+
| 1 | Block | All frame contents, excluding |
| | | lacing data. |
+-------+---------+-----------------------------------+
| 2 | Private | The track's private data. |
+-------+---------+-----------------------------------+
| 4 | Next | The next ContentEncoding (next |
| | | ContentEncodingOrder. Either the |
| | | data inside ContentCompression |
| | | and/or ContentEncryption).This |
| | | value SHOULD NOT be used. |
+-------+---------+-----------------------------------+
Table 22: ContentEncodingScope values
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.34.4. ContentEncodingType Element
name: ContentEncodingType
path: \Segment\Tracks\TrackEntry\ContentEncodings\ContentEncoding\Co
ntentEncodingType
id: 0x5033
minOccurs: 1
maxOccurs: 1
default: 0
type: uinteger
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definition: A value describing what kind of transformation is
applied.
restrictions:
+=======+=============+
| value | label |
+=======+=============+
| 0 | Compression |
+-------+-------------+
| 1 | Encryption |
+-------+-------------+
Table 23:
ContentEncodingType
values
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.34.5. ContentCompression Element
name: ContentCompression
path: \Segment\Tracks\TrackEntry\ContentEncodings\ContentEncoding\Co
ntentCompression
id: 0x5034
maxOccurs: 1
type: master
definition: Settings describing the compression used. This Element
MUST be present if the value of ContentEncodingType is 0 and
absent otherwise. Each block MUST be decompressable even if no
previous block is available in order not to prevent seeking.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.34.6. ContentCompAlgo Element
name: ContentCompAlgo
path: \Segment\Tracks\TrackEntry\ContentEncodings\ContentEncoding\Co
ntentCompression\ContentCompAlgo
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id: 0x4254
minOccurs: 1
maxOccurs: 1
default: 0
type: uinteger
definition: The compression algorithm used.
defined values:
+=======+===========+=========================================+
| value | label | definition |
+=======+===========+=========================================+
| 0 | zlib | zlib compression [RFC1950]. |
+-------+-----------+-----------------------------------------+
| 1 | bzlib | bzip2 compression [BZIP2], SHOULD NOT |
| | | be used; see usage notes. |
+-------+-----------+-----------------------------------------+
| 2 | lzo1x | Lempel-Ziv-Oberhumer compression [LZO], |
| | | SHOULD NOT be used; see usage notes. |
+-------+-----------+-----------------------------------------+
| 3 | Header | Octets in ContentCompSettings |
| | Stripping | (Section 8.1.4.1.34.7) have been |
| | | stripped from each frame. |
+-------+-----------+-----------------------------------------+
Table 24: ContentCompAlgo values
usage notes: Compression method "1" (bzlib) and "2" (lzo1x) are
lacking proper documentation on the format which limits
implementation possibilities. Due to licensing conflicts on
commonly available libraries compression methods "2" (lzo1x) does
not offer widespread interoperability. Decoding implementations
MAY support methods "1" and "2" as possible. The use of these
compression methods SHOULD NOT be used as a default.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.34.7. ContentCompSettings Element
name: ContentCompSettings
path: \Segment\Tracks\TrackEntry\ContentEncodings\ContentEncoding\Co
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ntentCompression\ContentCompSettings
id: 0x4255
maxOccurs: 1
type: binary
definition: Settings that might be needed by the decompressor. For
Header Stripping (ContentCompAlgo=3), the bytes that were removed
from the beginning of each frames of the track.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.34.8. ContentEncryption Element
name: ContentEncryption
path: \Segment\Tracks\TrackEntry\ContentEncodings\ContentEncoding\Co
ntentEncryption
id: 0x5035
maxOccurs: 1
type: master
definition: Settings describing the encryption used. This Element
MUST be present if the value of ContentEncodingType is 1
(encryption) and MUST be ignored otherwise.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.34.9. ContentEncAlgo Element
name: ContentEncAlgo
path: \Segment\Tracks\TrackEntry\ContentEncodings\ContentEncoding\Co
ntentEncryption\ContentEncAlgo
id: 0x47E1
minOccurs: 1
maxOccurs: 1
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default: 0
type: uinteger
definition: The encryption algorithm used. The value "0" means that
the contents have not been encrypted.
defined values:
+=======+===============+============================+
| value | label | definition |
+=======+===============+============================+
| 0 | Not encrypted | |
+-------+---------------+----------------------------+
| 1 | DES | Data Encryption Standard |
| | | (DES) [FIPS.46-3]. |
+-------+---------------+----------------------------+
| 2 | 3DES | Triple Data Encryption |
| | | Algorithm [RFC1851]. |
+-------+---------------+----------------------------+
| 3 | Twofish | Twofish Encryption |
| | | Algorithm [Twofish]. |
+-------+---------------+----------------------------+
| 4 | Blowfish | Blowfish Encryption |
| | | Algorithm [Blowfish]. |
+-------+---------------+----------------------------+
| 5 | AES | Advanced Encryption |
| | | Standard (AES) [FIPS.197]. |
+-------+---------------+----------------------------+
Table 25: ContentEncAlgo values
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.34.10. ContentEncKeyID Element
name: ContentEncKeyID
path: \Segment\Tracks\TrackEntry\ContentEncodings\ContentEncoding\Co
ntentEncryption\ContentEncKeyID
id: 0x47E2
maxOccurs: 1
type: binary
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definition: For public key algorithms this is the ID of the public
key the the data was encrypted with.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.34.11. ContentEncAESSettings Element
name: ContentEncAESSettings
path: \Segment\Tracks\TrackEntry\ContentEncodings\ContentEncoding\Co
ntentEncryption\ContentEncAESSettings
id: 0x47E7
maxOccurs: 1
type: master
minver: 4
definition: Settings describing the encryption algorithm used. It
MUST be ignored if ContentEncAlgo is not AES (5).
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.4.1.34.12. AESSettingsCipherMode Element
name: AESSettingsCipherMode
path: \Segment\Tracks\TrackEntry\ContentEncodings\ContentEncoding\Co
ntentEncryption\ContentEncAESSettings\AESSettingsCipherMode
id: 0x47E8
minOccurs: 1
maxOccurs: 1
type: uinteger
minver: 4
definition: The AES cipher mode used in the encryption. It MUST be
ignored if ContentEncAlgo is not AES (5).
defined values:
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+=======+=========+=====================================+
| value | label | definition |
+=======+=========+=====================================+
| 1 | AES-CTR | Counter [SP.800-38A]. |
+-------+---------+-------------------------------------+
| 2 | AES-CBC | Cipher Block Chaining [SP.800-38A]. |
+-------+---------+-------------------------------------+
Table 26: AESSettingsCipherMode values
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.5. Cues Element
name: Cues
path: \Segment\Cues
id: 0x1C53BB6B
minOccurs: see implementation notes
maxOccurs: 1
type: master
definition: A Top-Level Element to speed seeking access. All
entries are local to the Segment.
notes:
+===========+====================================================+
| attribute | note |
+===========+====================================================+
| minOccurs | This Element SHOULD be set when the Segment is not |
| | transmitted as a live stream (see #livestreaming). |
+-----------+----------------------------------------------------+
Table 27: Cues implementation notes
8.1.5.1. CuePoint Element
name: CuePoint
path: \Segment\Cues\CuePoint
id: 0xBB
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minOccurs: 1
type: master
definition: Contains all information relative to a seek point in the
Segment.
8.1.5.1.1. CueTime Element
name: CueTime
path: \Segment\Cues\CuePoint\CueTime
id: 0xB3
minOccurs: 1
maxOccurs: 1
type: uinteger
definition: Absolute timestamp of the seek point, expressed in
Matroska Ticks -- ie in nanoseconds; see Section 13.1.
8.1.5.1.2. CueTrackPositions Element
name: CueTrackPositions
path: \Segment\Cues\CuePoint\CueTrackPositions
id: 0xB7
minOccurs: 1
type: master
definition: Contain positions for different tracks corresponding to
the timestamp.
8.1.5.1.2.1. CueTrack Element
name: CueTrack
path: \Segment\Cues\CuePoint\CueTrackPositions\CueTrack
id: 0xF7
minOccurs: 1
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maxOccurs: 1
range: not 0
type: uinteger
definition: The track for which a position is given.
8.1.5.1.2.2. CueClusterPosition Element
name: CueClusterPosition
path: \Segment\Cues\CuePoint\CueTrackPositions\CueClusterPosition
id: 0xF1
minOccurs: 1
maxOccurs: 1
type: uinteger
definition: The Segment Position of the Cluster containing the
associated Block.
8.1.5.1.2.3. CueRelativePosition Element
name: CueRelativePosition
path: \Segment\Cues\CuePoint\CueTrackPositions\CueRelativePosition
id: 0xF0
maxOccurs: 1
type: uinteger
minver: 4
definition: The relative position inside the Cluster of the
referenced SimpleBlock or BlockGroup with 0 being the first
possible position for an Element inside that Cluster.
8.1.5.1.2.4. CueDuration Element
name: CueDuration
path: \Segment\Cues\CuePoint\CueTrackPositions\CueDuration
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id: 0xB2
maxOccurs: 1
type: uinteger
minver: 4
definition: The duration of the block, expressed in Segment Ticks
which is based on TimestampScale; see Section 13.1. If missing,
the track's DefaultDuration does not apply and no duration
information is available in terms of the cues.
8.1.5.1.2.5. CueBlockNumber Element
name: CueBlockNumber
path: \Segment\Cues\CuePoint\CueTrackPositions\CueBlockNumber
id: 0x5378
maxOccurs: 1
range: not 0
type: uinteger
definition: Number of the Block in the specified Cluster.
8.1.5.1.2.6. CueCodecState Element
name: CueCodecState
path: \Segment\Cues\CuePoint\CueTrackPositions\CueCodecState
id: 0xEA
minOccurs: 1
maxOccurs: 1
default: 0
type: uinteger
minver: 2
definition: The Segment Position of the Codec State corresponding to
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this Cue Element. 0 means that the data is taken from the initial
Track Entry.
8.1.5.1.2.7. CueReference Element
name: CueReference
path: \Segment\Cues\CuePoint\CueTrackPositions\CueReference
id: 0xDB
type: master
minver: 2
definition: The Clusters containing the referenced Blocks.
8.1.5.1.2.8. CueRefTime Element
name: CueRefTime
path: \Segment\Cues\CuePoint\CueTrackPositions\CueReference\CueRefTi
me
id: 0x96
minOccurs: 1
maxOccurs: 1
type: uinteger
minver: 2
definition: Timestamp of the referenced Block, expressed in Matroska
Ticks -- ie in nanoseconds; see Section 13.1.
8.1.6. Attachments Element
name: Attachments
path: \Segment\Attachments
id: 0x1941A469
maxOccurs: 1
type: master
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definition: Contain attached files.
8.1.6.1. AttachedFile Element
name: AttachedFile
path: \Segment\Attachments\AttachedFile
id: 0x61A7
minOccurs: 1
type: master
definition: An attached file.
8.1.6.1.1. FileDescription Element
name: FileDescription
path: \Segment\Attachments\AttachedFile\FileDescription
id: 0x467E
maxOccurs: 1
type: utf-8
definition: A human-friendly name for the attached file.
8.1.6.1.2. FileName Element
name: FileName
path: \Segment\Attachments\AttachedFile\FileName
id: 0x466E
minOccurs: 1
maxOccurs: 1
type: utf-8
definition: Filename of the attached file.
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8.1.6.1.3. FileMimeType Element
name: FileMimeType
path: \Segment\Attachments\AttachedFile\FileMimeType
id: 0x4660
minOccurs: 1
maxOccurs: 1
type: string
definition: MIME type of the file.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.6.1.4. FileData Element
name: FileData
path: \Segment\Attachments\AttachedFile\FileData
id: 0x465C
minOccurs: 1
maxOccurs: 1
type: binary
definition: The data of the file.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.6.1.5. FileUID Element
name: FileUID
path: \Segment\Attachments\AttachedFile\FileUID
id: 0x46AE
minOccurs: 1
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maxOccurs: 1
range: not 0
type: uinteger
definition: Unique ID representing the file, as random as possible.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.7. Chapters Element
name: Chapters
path: \Segment\Chapters
id: 0x1043A770
maxOccurs: 1
type: master
recurring: 1
definition: A system to define basic menus and partition data. For
more detailed information, look at the Chapters explanation in
Section 22.
8.1.7.1. EditionEntry Element
name: EditionEntry
path: \Segment\Chapters\EditionEntry
id: 0x45B9
minOccurs: 1
type: master
definition: Contains all information about a Segment edition.
8.1.7.1.1. EditionUID Element
name: EditionUID
path: \Segment\Chapters\EditionEntry\EditionUID
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id: 0x45BC
maxOccurs: 1
range: not 0
type: uinteger
definition: A unique ID to identify the edition. It's useful for
tagging an edition.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
8.1.7.1.2. EditionFlagDefault Element
name: EditionFlagDefault
path: \Segment\Chapters\EditionEntry\EditionFlagDefault
id: 0x45DB
minOccurs: 1
maxOccurs: 1
range: 0-1
default: 0
type: uinteger
definition: Set to 1 if the edition SHOULD be used as the default
one.
8.1.7.1.3. EditionFlagOrdered Element
name: EditionFlagOrdered
path: \Segment\Chapters\EditionEntry\EditionFlagOrdered
id: 0x45DD
minOccurs: 1
maxOccurs: 1
range: 0-1
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default: 0
type: uinteger
definition: Set to 1 if the chapters can be defined multiple times
and the order to play them is enforced; see Section 22.1.3.
8.1.7.1.4. ChapterAtom Element
name: ChapterAtom
path: \Segment\Chapters\EditionEntry\+ChapterAtom
id: 0xB6
minOccurs: 1
type: master
recursive: 1
definition: Contains the atom information to use as the chapter atom
(apply to all tracks).
8.1.7.1.4.1. ChapterUID Element
name: ChapterUID
path: \Segment\Chapters\EditionEntry\+ChapterAtom\ChapterUID
id: 0x73C4
minOccurs: 1
maxOccurs: 1
range: not 0
type: uinteger
definition: A unique ID to identify the Chapter.
usage notes: The value of this Element SHOULD be kept the same when
making a direct stream copy to another file.
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8.1.7.1.4.2. ChapterStringUID Element
name: ChapterStringUID
path: \Segment\Chapters\EditionEntry\+ChapterAtom\ChapterStringUID
id: 0x5654
maxOccurs: 1
type: utf-8
minver: 3
definition: A unique string ID to identify the Chapter. Use for
WebVTT cue identifier storage [WebVTT].
8.1.7.1.4.3. ChapterTimeStart Element
name: ChapterTimeStart
path: \Segment\Chapters\EditionEntry\+ChapterAtom\ChapterTimeStart
id: 0x91
minOccurs: 1
maxOccurs: 1
type: uinteger
definition: Timestamp of the start of Chapter, expressed in Matroska
Ticks -- ie in nanoseconds; see Section 13.1.
8.1.7.1.4.4. ChapterTimeEnd Element
name: ChapterTimeEnd
path: \Segment\Chapters\EditionEntry\+ChapterAtom\ChapterTimeEnd
id: 0x92
minOccurs: see implementation notes
maxOccurs: 1
type: uinteger
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definition: Timestamp of the end of Chapter timestamp excluded,
expressed in Matroska Ticks -- ie in nanoseconds; see
Section 13.1. The value MUST be greater than or equal to the
ChapterTimeStart of the same ChapterAtom.
usage notes: The ChapterTimeEnd timestamp value being excluded, it
MUST take in account the duration of the last frame it includes,
especially for the ChapterAtom using the last frames of the
Segment.
notes:
+===========+====================================================+
| attribute | note |
+===========+====================================================+
| minOccurs | ChapterTimeEnd MUST be set (minOccurs=1) if the |
| | Edition is an ordered edition; see Section 22.1.3, |
| | unless it's a Parent Chapter; see Section 22.2.3 |
+-----------+----------------------------------------------------+
Table 28: ChapterTimeEnd implementation notes
8.1.7.1.4.5. ChapterFlagHidden Element
name: ChapterFlagHidden
path: \Segment\Chapters\EditionEntry\+ChapterAtom\ChapterFlagHidden
id: 0x98
minOccurs: 1
maxOccurs: 1
range: 0-1
default: 0
type: uinteger
definition: Set to 1 if a chapter is hidden. Hidden chapters SHOULD
NOT be available to the user interface (but still to Control
Tracks; see Section 22.2.5 on Chapter flags).
8.1.7.1.4.6. ChapterSegmentUID Element
name: ChapterSegmentUID
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path: \Segment\Chapters\EditionEntry\+ChapterAtom\ChapterSegmentUID
id: 0x6E67
minOccurs: see implementation notes
maxOccurs: 1
range: >0
type: binary
definition: The SegmentUID of another Segment to play during this
chapter.
usage notes: The value MUST NOT be the SegmentUID value of the
Segment it belongs to.
notes:
+===========+=============================================+
| attribute | note |
+===========+=============================================+
| minOccurs | ChapterSegmentUID MUST be set (minOccurs=1) |
| | if ChapterSegmentEditionUID is used; see |
| | Section 19.2 on medium-linking Segments. |
+-----------+---------------------------------------------+
Table 29: ChapterSegmentUID implementation notes
8.1.7.1.4.7. ChapterSegmentEditionUID Element
name: ChapterSegmentEditionUID
path: \Segment\Chapters\EditionEntry\+ChapterAtom\ChapterSegmentEdit
ionUID
id: 0x6EBC
maxOccurs: 1
range: not 0
type: uinteger
definition: The EditionUID to play from the Segment linked in
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ChapterSegmentUID. If ChapterSegmentEditionUID is undeclared,
then no Edition of the linked Segment is used; see Section 19.2 on
medium-linking Segments.
8.1.7.1.4.8. ChapterPhysicalEquiv Element
name: ChapterPhysicalEquiv
path: \Segment\Chapters\EditionEntry\+ChapterAtom\ChapterPhysicalEqu
iv
id: 0x63C3
maxOccurs: 1
type: uinteger
definition: Specify the physical equivalent of this ChapterAtom like
"DVD" (60) or "SIDE" (50); see Section 22.4 for a complete list of
values.
8.1.7.1.4.9. ChapterDisplay Element
name: ChapterDisplay
path: \Segment\Chapters\EditionEntry\+ChapterAtom\ChapterDisplay
id: 0x80
type: master
definition: Contains all possible strings to use for the chapter
display.
8.1.7.1.4.10. ChapString Element
name: ChapString
path: \Segment\Chapters\EditionEntry\+ChapterAtom\ChapterDisplay\Cha
pString
id: 0x85
minOccurs: 1
maxOccurs: 1
type: utf-8
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definition: Contains the string to use as the chapter atom.
8.1.7.1.4.11. ChapLanguage Element
name: ChapLanguage
path: \Segment\Chapters\EditionEntry\+ChapterAtom\ChapterDisplay\Cha
pLanguage
id: 0x437C
minOccurs: 1
default: eng
type: string
definition: A language corresponding to the string, in the
bibliographic ISO-639-2 form [ISO639-2]. This Element MUST be
ignored if a ChapLanguageIETF Element is used within the same
ChapterDisplay Element.
8.1.7.1.4.12. ChapLanguageIETF Element
name: ChapLanguageIETF
path: \Segment\Chapters\EditionEntry\+ChapterAtom\ChapterDisplay\Cha
pLanguageIETF
id: 0x437D
type: string
minver: 4
definition: Specifies a language corresponding to the ChapString in
the format defined in [BCP47] and using the IANA Language Subtag
Registry [IANALangRegistry]. If a ChapLanguageIETF Element is
used, then any ChapLanguage and ChapCountry Elements used in the
same ChapterDisplay MUST be ignored.
8.1.7.1.4.13. ChapCountry Element
name: ChapCountry
path: \Segment\Chapters\EditionEntry\+ChapterAtom\ChapterDisplay\Cha
pCountry
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id: 0x437E
type: string
definition: A country corresponding to the string, using the same 2
octets country-codes as in Internet domains [IANADomains] based on
[ISO3166-1] alpha-2 codes. This Element MUST be ignored if a
ChapLanguageIETF Element is used within the same ChapterDisplay
Element.
8.1.7.1.4.14. ChapProcess Element
name: ChapProcess
path: \Segment\Chapters\EditionEntry\+ChapterAtom\ChapProcess
id: 0x6944
type: master
definition: Contains all the commands associated to the Atom.
8.1.7.1.4.15. ChapProcessCodecID Element
name: ChapProcessCodecID
path: \Segment\Chapters\EditionEntry\+ChapterAtom\ChapProcess\ChapPr
ocessCodecID
id: 0x6955
minOccurs: 1
maxOccurs: 1
default: 0
type: uinteger
definition: Contains the type of the codec used for the processing.
A value of 0 means native Matroska processing (to be defined), a
value of 1 means the DVD command set is used; see Section 22.3 on
DVD menus. More codec IDs can be added later.
8.1.7.1.4.16. ChapProcessPrivate Element
name: ChapProcessPrivate
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path: \Segment\Chapters\EditionEntry\+ChapterAtom\ChapProcess\ChapPr
ocessPrivate
id: 0x450D
maxOccurs: 1
type: binary
definition: Some optional data attached to the ChapProcessCodecID
information. For ChapProcessCodecID = 1, it is the "DVD level"
equivalent; see Section 22.3 on DVD menus.
8.1.7.1.4.17. ChapProcessCommand Element
name: ChapProcessCommand
path: \Segment\Chapters\EditionEntry\+ChapterAtom\ChapProcess\ChapPr
ocessCommand
id: 0x6911
type: master
definition: Contains all the commands associated to the Atom.
8.1.7.1.4.18. ChapProcessTime Element
name: ChapProcessTime
path: \Segment\Chapters\EditionEntry\+ChapterAtom\ChapProcess\ChapPr
ocessCommand\ChapProcessTime
id: 0x6922
minOccurs: 1
maxOccurs: 1
type: uinteger
definition: Defines when the process command SHOULD be handled
restrictions:
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+=======+===============================+
| value | label |
+=======+===============================+
| 0 | during the whole chapter |
+-------+-------------------------------+
| 1 | before starting playback |
+-------+-------------------------------+
| 2 | after playback of the chapter |
+-------+-------------------------------+
Table 30: ChapProcessTime values
8.1.7.1.4.19. ChapProcessData Element
name: ChapProcessData
path: \Segment\Chapters\EditionEntry\+ChapterAtom\ChapProcess\ChapPr
ocessCommand\ChapProcessData
id: 0x6933
minOccurs: 1
maxOccurs: 1
type: binary
definition: Contains the command information. The data SHOULD be
interpreted depending on the ChapProcessCodecID value. For
ChapProcessCodecID = 1, the data correspond to the binary DVD cell
pre/post commands; see Section 22.3 on DVD menus.
8.1.8. Tags Element
name: Tags
path: \Segment\Tags
id: 0x1254C367
type: master
definition: Element containing metadata describing Tracks, Editions,
Chapters, Attachments, or the Segment as a whole. A list of valid
tags can be found in [MatroskaTags].
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8.1.8.1. Tag Element
name: Tag
path: \Segment\Tags\Tag
id: 0x7373
minOccurs: 1
type: master
definition: A single metadata descriptor.
8.1.8.1.1. Targets Element
name: Targets
path: \Segment\Tags\Tag\Targets
id: 0x63C0
minOccurs: 1
maxOccurs: 1
type: master
definition: Specifies which other elements the metadata represented
by the Tag applies to. If empty or not present, then the Tag
describes everything in the Segment.
8.1.8.1.1.1. TargetTypeValue Element
name: TargetTypeValue
path: \Segment\Tags\Tag\Targets\TargetTypeValue
id: 0x68CA
minOccurs: 1
maxOccurs: 1
default: 50
type: uinteger
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definition: A number to indicate the logical level of the target.
defined values:
+=======+==========================+================================+
| value | label | definition |
+=======+==========================+================================+
| 70 | COLLECTION | The highest hierarchical level |
| | | that tags can describe. |
+-------+--------------------------+--------------------------------+
| 60 | EDITION / ISSUE / | A list of lower levels grouped |
| | VOLUME / OPUS / | together. |
| | SEASON / SEQUEL | |
+-------+--------------------------+--------------------------------+
| 50 | ALBUM / OPERA / | The most common grouping level |
| | CONCERT / MOVIE / | of music and video (equals to |
| | EPISODE / CONCERT | an episode for TV series). |
+-------+--------------------------+--------------------------------+
| 40 | PART / SESSION | When an album or episode has |
| | | different logical parts. |
+-------+--------------------------+--------------------------------+
| 30 | TRACK / SONG / | The common parts of an album |
| | CHAPTER | or movie. |
+-------+--------------------------+--------------------------------+
| 20 | SUBTRACK / PART / | Corresponds to parts of a |
| | MOVEMENT / SCENE | track for audio (like a |
| | | movement). |
+-------+--------------------------+--------------------------------+
| 10 | SHOT | The lowest hierarchy found in |
| | | music or movies. |
+-------+--------------------------+--------------------------------+
Table 31: TargetTypeValue values
8.1.8.1.1.2. TargetType Element
name: TargetType
path: \Segment\Tags\Tag\Targets\TargetType
id: 0x63CA
maxOccurs: 1
type: string
definition: An informational string that can be used to display the
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logical level of the target like "ALBUM", "TRACK", "MOVIE",
"CHAPTER", etc ; see Section 6.4 of [MatroskaTags].
restrictions:
+============+============+
| value | label |
+============+============+
| COLLECTION | COLLECTION |
+------------+------------+
| EDITION | EDITION |
+------------+------------+
| ISSUE | ISSUE |
+------------+------------+
| VOLUME | VOLUME |
+------------+------------+
| OPUS | OPUS |
+------------+------------+
| SEASON | SEASON |
+------------+------------+
| SEQUEL | SEQUEL |
+------------+------------+
| ALBUM | ALBUM |
+------------+------------+
| OPERA | OPERA |
+------------+------------+
| CONCERT | CONCERT |
+------------+------------+
| MOVIE | MOVIE |
+------------+------------+
| EPISODE | EPISODE |
+------------+------------+
| PART | PART |
+------------+------------+
| SESSION | SESSION |
+------------+------------+
| TRACK | TRACK |
+------------+------------+
| SONG | SONG |
+------------+------------+
| CHAPTER | CHAPTER |
+------------+------------+
| SUBTRACK | SUBTRACK |
+------------+------------+
| PART | PART |
+------------+------------+
| MOVEMENT | MOVEMENT |
+------------+------------+
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| SCENE | SCENE |
+------------+------------+
| SHOT | SHOT |
+------------+------------+
Table 32: TargetType values
8.1.8.1.1.3. TagTrackUID Element
name: TagTrackUID
path: \Segment\Tags\Tag\Targets\TagTrackUID
id: 0x63C5
default: 0
type: uinteger
definition: A unique ID to identify the Track(s) the tags belong to.
usage notes: If the value is 0 at this level, the tags apply to all
tracks in the Segment. If set to any other value, it MUST match
the TrackUID value of a track found in this Segment.
8.1.8.1.1.4. TagEditionUID Element
name: TagEditionUID
path: \Segment\Tags\Tag\Targets\TagEditionUID
id: 0x63C9
default: 0
type: uinteger
definition: A unique ID to identify the EditionEntry(s) the tags
belong to.
usage notes: If the value is 0 at this level, the tags apply to all
editions in the Segment. If set to any other value, it MUST match
the EditionUID value of an edition found in this Segment.
8.1.8.1.1.5. TagChapterUID Element
name: TagChapterUID
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path: \Segment\Tags\Tag\Targets\TagChapterUID
id: 0x63C4
default: 0
type: uinteger
definition: A unique ID to identify the Chapter(s) the tags belong
to.
usage notes: If the value is 0 at this level, the tags apply to all
chapters in the Segment. If set to any other value, it MUST match
the ChapterUID value of a chapter found in this Segment.
8.1.8.1.1.6. TagAttachmentUID Element
name: TagAttachmentUID
path: \Segment\Tags\Tag\Targets\TagAttachmentUID
id: 0x63C6
default: 0
type: uinteger
definition: A unique ID to identify the Attachment(s) the tags
belong to.
usage notes: If the value is 0 at this level, the tags apply to all
the attachments in the Segment. If set to any other value, it
MUST match the FileUID value of an attachment found in this
Segment.
8.1.8.1.2. SimpleTag Element
name: SimpleTag
path: \Segment\Tags\Tag\+SimpleTag
id: 0x67C8
minOccurs: 1
type: master
recursive: 1
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definition: Contains general information about the target.
8.1.8.1.2.1. TagName Element
name: TagName
path: \Segment\Tags\Tag\+SimpleTag\TagName
id: 0x45A3
minOccurs: 1
maxOccurs: 1
type: utf-8
definition: The name of the Tag that is going to be stored.
8.1.8.1.2.2. TagLanguage Element
name: TagLanguage
path: \Segment\Tags\Tag\+SimpleTag\TagLanguage
id: 0x447A
minOccurs: 1
maxOccurs: 1
default: und
type: string
definition: Specifies the language of the tag specified, in the
Matroska languages form; see Section 6 on language codes. This
Element MUST be ignored if the TagLanguageIETF Element is used
within the same SimpleTag Element.
8.1.8.1.2.3. TagLanguageIETF Element
name: TagLanguageIETF
path: \Segment\Tags\Tag\+SimpleTag\TagLanguageIETF
id: 0x447B
maxOccurs: 1
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type: string
minver: 4
definition: Specifies the language used in the TagString according
to [BCP47] and using the IANA Language Subtag Registry
[IANALangRegistry]. If this Element is used, then any TagLanguage
Elements used in the same SimpleTag MUST be ignored.
8.1.8.1.2.4. TagDefault Element
name: TagDefault
path: \Segment\Tags\Tag\+SimpleTag\TagDefault
id: 0x4484
minOccurs: 1
maxOccurs: 1
range: 0-1
default: 1
type: uinteger
definition: A boolean value to indicate if this is the default/
original language to use for the given tag.
8.1.8.1.2.5. TagString Element
name: TagString
path: \Segment\Tags\Tag\+SimpleTag\TagString
id: 0x4487
maxOccurs: 1
type: utf-8
definition: The value of the Tag.
8.1.8.1.2.6. TagBinary Element
name: TagBinary
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path: \Segment\Tags\Tag\+SimpleTag\TagBinary
id: 0x4485
maxOccurs: 1
type: binary
definition: The values of the Tag, if it is binary. Note that this
cannot be used in the same SimpleTag as TagString.
9. Matroska Element Ordering
Except for the EBML Header and the CRC-32 Element, the EBML
specification does not require any particular storage order for
Elements. The Matroska specification however defines mandates and
recommendations for ordering certain Elements in order to facilitate
better playback, seeking, and editing efficiency. This section
describes and offers rationale for ordering requirements and
recommendations for Matroska.
9.1. Top-Level Elements
The Info Element is the only REQUIRED Top-Level Element in a Matroska
file. To be playable, Matroska MUST also contain at least one Tracks
Element and Cluster Element. The first Info Element and the first
Tracks Element MUST either be stored before the first Cluster Element
or both SHALL be referenced by a SeekHead Element occurring before
the first Cluster Element.
It is possible to edit a Matroska file after it has been created.
For example, chapters, tags, or attachments can be added. When new
Top-Level Elements are added to a Matroska file, the SeekHead
Element(s) MUST be updated so that the SeekHead Element(s) itemize
the identity and position of all Top-Level Elements. Editing,
removing, or adding Elements to a Matroska file often requires that
some existing Elements be voided or extended; therefore, it is
RECOMMENDED to use Void Elements as padding in between Top-Level
Elements.
9.2. CRC-32
As noted by the EBML specification, if a CRC-32 Element is used, then
the CRC-32 Element MUST be the first ordered Element within its
Parent Element. The Matroska specification recommends that CRC-32
Elements SHOULD NOT be used as an immediate Child Element of the
Segment Element; however all Top-Level Elements of an EBML Document
SHOULD include a CRC-32 Element as a Child Element.
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9.3. SeekHead
If used, the first SeekHead Element SHOULD be the first non-CRC-32
Child Element of the Segment Element. If a second SeekHead Element
is used, then the first SeekHead Element MUST reference the identity
and position of the second SeekHead. Additionally, the second
SeekHead Element MUST only reference Cluster Elements and not any
other Top-Level Element already contained within the first SeekHead
Element. The second SeekHead Element MAY be stored in any order
relative to the other Top-Level Elements. Whether one or two
SeekHead Element(s) are used, the SeekHead Element(s) MUST
collectively reference the identity and position of all Top-Level
Elements except for the first SeekHead Element.
It is RECOMMENDED that the first SeekHead Element be followed by a
Void Element to allow for the SeekHead Element to be expanded to
cover new Top-Level Elements that could be added to the Matroska
file, such as Tags, Chapters, and Attachments Elements.
9.4. Cues (index)
The Cues Element is RECOMMENDED to optimize seeking access in
Matroska. It is programmatically simpler to add the Cues Element
after all Cluster Elements have been written because this does not
require a prediction of how much space to reserve before writing the
Cluster Elements. However, storing the Cues Element before the
Cluster Elements can provide some seeking advantages. If the Cues
Element is present, then it SHOULD either be stored before the first
Cluster Element or be referenced by a SeekHead Element.
9.5. Info
The first Info Element SHOULD occur before the first Tracks Element
and first Cluster Element except when referenced by a SeekHead
Element.
9.6. Chapters Element
The Chapters Element SHOULD be placed before the Cluster Element(s).
The Chapters Element can be used during playback even if the user
does not need to seek. It immediately gives the user information
about what section is being read and what other sections are
available. In the case of Ordered Chapters it is RECOMMENDED to
evaluate the logical linking even before playing. The Chapters
Element SHOULD be placed before the first Tracks Element and after
the first Info Element.
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9.7. Attachments
The Attachments Element is not intended to be used by default when
playing the file, but could contain information relevant to the
content, such as cover art or fonts. Cover art is useful even before
the file is played and fonts could be needed before playback starts
for initialization of subtitles. The Attachments Element MAY be
placed before the first Cluster Element; however if the Attachments
Element is likely to be edited, then it SHOULD be placed after the
last Cluster Element.
9.8. Tags
The Tags Element is most subject to changes after the file was
originally created. For easier editing, the Tags Element SHOULD be
placed at the end of the Segment Element, even after the Attachments
Element. On the other hand, it is inconvenient to have to seek in
the Segment for tags, especially for network streams. So it's better
if the Tags Element is found early in the stream. When editing the
Tags Element, the original Tags Element at the beginning can be
overwritten with a Void Element and a new Tags Element written at the
end of the Segment Element. The file size will only marginally
change.
9.9. Optimum layout from a muxer
* SeekHead
* Info
* Tracks
* Chapters
* Attachments
* Tags
* Clusters
* Cues
9.10. Optimum layout after editing tags
* SeekHead
* Info
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* Tracks
* Chapters
* Attachments
* Void
* Clusters
* Cues
* Tags
9.11. Optimum layout with Cues at the front
* SeekHead
* Info
* Tracks
* Chapters
* Attachments
* Tags
* Cues
* Clusters --- title: Specification Notes ---
10. Unknown elements
Matroska is based upon the principle that a reading application does
not have to support 100% of the specifications in order to be able to
play the file. A Matroska file therefore contains version indicators
that tell a reading application what to expect.
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It is possible and valid to have the version fields indicate that the
file contains Matroska Elements from a higher specification version
number while signaling that a reading application MUST only support a
lower version number properly in order to play it back (possibly with
a reduced feature set). For example, a reading application
supporting at least Matroska version V reading a file whose
DocTypeReadVersion field is equal to or lower than V MUST skip
Matroska/EBML Elements it encounters but does not know about if that
unknown element fits into the size constraints set by the current
Parent Element.
11. DefaultDecodedFieldDuration
The DefaultDecodedFieldDuration Element can signal to the displaying
application how often fields of a video sequence will be available
for displaying. It can be used for both interlaced and progressive
content. If the video sequence is signaled as interlaced, then the
period between two successive fields at the output of the decoding
process equals DefaultDecodedFieldDuration.
For video sequences signaled as progressive, it is twice the value of
DefaultDecodedFieldDuration.
These values are valid at the end of the decoding process before
post-processing (such as deinterlacing or inverse telecine) is
applied.
Examples:
* Blu-ray movie: 1000000000ns/(48/1.001) = 20854167ns
* PAL broadcast/DVD: 1000000000ns/(50/1.000) = 20000000ns
* N/ATSC broadcast: 1000000000ns/(60/1.001) = 16683333ns
* hard-telecined DVD: 1000000000ns/(60/1.001) = 16683333ns (60
encoded interlaced fields per second)
* soft-telecined DVD: 1000000000ns/(60/1.001) = 16683333ns (48
encoded interlaced fields per second, with "repeat_first_field =
1")
12. Block Structure
Bit 0 is the most significant bit.
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Frames using references SHOULD be stored in "coding order". That
means the references first, and then the frames referencing them. A
consequence is that timestamps might not be consecutive. But a frame
with a past timestamp MUST reference a frame already known, otherwise
it's considered bad/void.
12.1. Block Header
+========+========+=============================================+
| Offset | Player | Description |
+========+========+=============================================+
| 0x00+ | MUST | Track Number (Track Entry). It is coded in |
| | | EBML like form (1 octet if the value is < |
| | | 0x80, 2 if < 0x4000, etc) (most significant |
| | | bits set to increase the range). |
+--------+--------+---------------------------------------------+
| 0x01+ | MUST | Timestamp (relative to Cluster timestamp, |
| | | signed int16) |
+--------+--------+---------------------------------------------+
Table 33: Block Header base parts
12.2. Block Header Flags
+========+=====+========+====================================+
| Offset | Bit | Player | Description |
+========+=====+========+====================================+
| 0x03+ | 0-3 | - | Reserved, set to 0 |
+--------+-----+--------+------------------------------------+
| 0x03+ | 4 | - | Invisible, the codec SHOULD decode |
| | | | this frame but not display it |
+--------+-----+--------+------------------------------------+
| 0x03+ | 5-6 | MUST | Lacing |
+--------+-----+--------+------------------------------------+
| | | | * 00 : no lacing |
+--------+-----+--------+------------------------------------+
| | | | * 01 : Xiph lacing |
+--------+-----+--------+------------------------------------+
| | | | * 11 : EBML lacing |
+--------+-----+--------+------------------------------------+
| | | | * 10 : fixed-size lacing |
+--------+-----+--------+------------------------------------+
| 0x03+ | 7 | - | not used |
+--------+-----+--------+------------------------------------+
Table 34: Block Header flags part
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12.3. SimpleBlock Structure
The SimpleBlock is inspired by the Block structure; see Section 12.
The main differences are the added Keyframe flag and Discardable
flag. Otherwise everything is the same.
Bit 0 is the most significant bit.
Frames using references SHOULD be stored in "coding order". That
means the references first, and then the frames referencing them. A
consequence is that timestamps might not be consecutive. But a frame
with a past timestamp MUST reference a frame already known, otherwise
it's considered bad/void.
12.3.1. SimpleBlock Header
+========+========+=============================================+
| Offset | Player | Description |
+========+========+=============================================+
| 0x00+ | MUST | Track Number (Track Entry). It is coded in |
| | | EBML like form (1 octet if the value is < |
| | | 0x80, 2 if < 0x4000, etc) (most significant |
| | | bits set to increase the range). |
+--------+--------+---------------------------------------------+
| 0x01+ | MUST | Timestamp (relative to Cluster timestamp, |
| | | signed int16) |
+--------+--------+---------------------------------------------+
Table 35: SimpleBlock Header base parts
12.3.2. SimpleBlock Header Flags
+========+=====+========+==========================================+
| Offset | Bit | Player | Description |
+========+=====+========+==========================================+
| 0x03+ | 0 | - | Keyframe, set when the Block contains |
| | | | only keyframes |
+--------+-----+--------+------------------------------------------+
| 0x03+ | 1-3 | - | Reserved, set to 0 |
+--------+-----+--------+------------------------------------------+
| 0x03+ | 4 | - | Invisible, the codec SHOULD decode this |
| | | | frame but not display it |
+--------+-----+--------+------------------------------------------+
| 0x03+ | 5-6 | MUST | Lacing |
+--------+-----+--------+------------------------------------------+
| | | | * 00 : no lacing |
+--------+-----+--------+------------------------------------------+
| | | | * 01 : Xiph lacing |
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+--------+-----+--------+------------------------------------------+
| | | | * 11 : EBML lacing |
+--------+-----+--------+------------------------------------------+
| | | | * 10 : fixed-size lacing |
+--------+-----+--------+------------------------------------------+
| 0x03+ | 7 | - | Discardable, the frames of the Block can |
| | | | be discarded during playing if needed |
+--------+-----+--------+------------------------------------------+
Table 36: SimpleBlock Header flags part
12.4. Block Lacing
Lacing is a mechanism to save space when storing data. It is
typically used for small blocks of data (referred to as frames in
Matroska). It packs multiple frames into a single Block or
SimpleBlock.
Lacing MUST NOT be used to store a single frame in a Block or
SimpleBlock.
There are 3 types of lacing:
1. Xiph, inspired by what is found in the Ogg container [RFC3533]
2. EBML, which is the same with sizes coded differently
3. fixed-size, where the size is not coded
When lacing is not used, i.e. to store a single frame, the lacing
bits 5 and 6 of the Block or SimpleBlock MUST be set to zero.
For example, a user wants to store 3 frames of the same track. The
first frame is 800 octets long, the second is 500 octets long and the
third is 1000 octets long. As these data are small, they can be
stored in a lace to save space.
It is possible not to use lacing at all and just store a single frame
without any extra data. When the FlagLacing -- Section 8.1.4.1.12 --
is set to "0" all blocks of that track MUST NOT use lacing.
12.4.1. No lacing
When no lacing is used, the number of frames in the lace is ommitted
and only one frame can be stored in the Block. The bits 5-6 of the
Block Header flags are set to 00.
The Block for a 800 octets frame is as follows:
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+==============+=========+===================+
| Block Octets | Value | Description |
+==============+=========+===================+
| 4-803 | <frame> | Single frame data |
+--------------+---------+-------------------+
Table 37: No lacing
When a Block contains a single frame, it MUST use this No lacing
mode.
12.4.2. Xiph lacing
The Xiph lacing uses the same coding of size as found in the Ogg
container [RFC3533]. The bits 5-6 of the Block Header flags are set
to 01.
The Block data with laced frames is stored as follows:
* Lacing Head on 1 Octet: Number of frames in the lace minus 1.
* Lacing size of each frame except the last one.
* Binary data of each frame consecutively.
The lacing size is split into 255 values, stored as unsigned octets
-- for example, 500 is coded 255;245 or [0xFF 0xF5]. A frame with a
size multiple of 255 is coded with a 0 at the end of the size -- for
example, 765 is coded 255;255;255;0 or [0xFF 0xFF 0xFF 0x00].
The size of the last frame is deduced from the size remaining in the
Block after the other frames.
Because large sizes result in large coding of the sizes, it is
RECOMMENDED to use Xiph lacing only with small frames.
In our example, the 800, 500 and 1000 frames are stored with Xiph
lacing in a Block as follows:
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+=============+=====================+==========================+
| Block Octet | Value | Description |
+=============+=====================+==========================+
| 4 | 0x02 | Number of frames minus 1 |
+-------------+---------------------+--------------------------+
| 5-8 | 0xFF 0xFF 0xFF 0x23 | Size of the first frame |
| | | (255;255;255;35) |
+-------------+---------------------+--------------------------+
| 9-10 | 0xFF 0xF5 | Size of the second frame |
| | | (255;245) |
+-------------+---------------------+--------------------------+
| 11-810 | | First frame data |
+-------------+---------------------+--------------------------+
| 811-1310 | | Second frame data |
+-------------+---------------------+--------------------------+
| 1311-2310 | | Third frame data |
+-------------+---------------------+--------------------------+
Table 38: Xiph lacing example
The Block is 2311 octets large and the last frame starts at 1311, so
we can deduce the size of the last frame is 2311 - 1311 = 1000.
12.4.3. EBML lacing
The EBML lacing encodes the frame size with an EBML-like encoding
[RFC8794]. The bits 5-6 of the Block Header flags are set to 11.
The Block data with laced frames is stored as follows:
* Lacing Head on 1 Octet: Number of frames in the lace minus 1.
* Lacing size of each frame except the last one.
* Binary data of each frame consecutively.
The first frame size is encoded as an EBML Unsigned Integer Element
value. The other frame sizes are encoded as a difference with the
previous frame size as EBML Signed Integer Element values. That
corresponds to an EBML Data Size Values with two's complement
notation with the leftmost bit being the sign bit as found in
[RFC8794], giving this range of values:
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+==========================+=======================================+
| Bit Representation | Value |
+==========================+=======================================+
| 1xxx xxxx | value -(2^6-1) to 2^6-1 (ie 0 to |
| | 2^7-2 minus 2^6-1, half of the range) |
+--------------------------+---------------------------------------+
| 01xx xxxx xxxx xxxx | value -(2^13-1) to 2^13-1 |
+--------------------------+---------------------------------------+
| 001x xxxx xxxx xxxx xxxx | value -(2^20-1) to 2^20-1 |
| xxxx | |
+--------------------------+---------------------------------------+
| 0001 xxxx xxxx xxxx xxxx | value -(2^27-1) to 2^27-1 |
| xxxx xxxx xxxx | |
+--------------------------+---------------------------------------+
| 0000 1xxx xxxx xxxx xxxx | value -(2^34-1) to 2^34-1 |
| xxxx xxxx xxxx xxxx xxxx | |
+--------------------------+---------------------------------------+
| 0000 01xx xxxx xxxx xxxx | value -(2^41-1) to 2^41-1 |
| xxxx xxxx xxxx xxxx xxxx | |
| xxxx xxxx | |
+--------------------------+---------------------------------------+
| 0000 001x xxxx xxxx xxxx | value -(2^48-1) to 2^48-1 |
| xxxx xxxx xxxx xxxx xxxx | |
| xxxx xxxx xxxx xxxx | |
+--------------------------+---------------------------------------+
Table 39: EBML Lacing bits usage
In our example, the 800, 500 and 1000 frames are stored with EBML
lacing in a Block as follows:
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+==============+===========+=====================================+
| Block Octets | Value | Description |
+==============+===========+=====================================+
| 4 | 0x02 | Number of frames minus 1 |
+--------------+-----------+-------------------------------------+
| 5-6 | 0x43 0x20 | Size of the first frame (800 = |
| | | 0x320 + 0x4000) |
+--------------+-----------+-------------------------------------+
| 7-8 | 0x5E 0xD3 | Size of the second frame (500 - 800 |
| | | = -300 = - 0x12C + 0x1FFF + 0x4000) |
+--------------+-----------+-------------------------------------+
| 8-807 | <frame1> | First frame data |
+--------------+-----------+-------------------------------------+
| 808-1307 | <frame2> | Second frame data |
+--------------+-----------+-------------------------------------+
| 1308-2307 | <frame3> | Third frame data |
+--------------+-----------+-------------------------------------+
Table 40: EBML lacing example
The Block is 2308 octets large and the last frame starts at 1308, so
we can deduce the size of the last frame is 2308 - 1308 = 1000.
12.4.4. Fixed-size lacing
The Fixed-size lacing doesn't store the frame size, only the number
of frames in the lace. Each frame MUST have the same size. The
frame size of each frame is deduced from the total size of the Block.
The bits 5-6 of the Block Header flags are set to 10.
The Block data with laced frames is stored as follows:
* Lacing Head on 1 Octet: Number of frames in the lace minus 1.
* Binary data of each frame consecutively.
For example, for 3 frames of 800 octets each:
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+==============+==========+==========================+
| Block Octets | Value | Description |
+==============+==========+==========================+
| 4 | 0x02 | Number of frames minus 1 |
+--------------+----------+--------------------------+
| 5-804 | <frame1> | First frame data |
+--------------+----------+--------------------------+
| 805-1604 | <frame2> | Second frame data |
+--------------+----------+--------------------------+
| 1605-2404 | <frame3> | Third frame data |
+--------------+----------+--------------------------+
Table 41: Fixed-size lacing example
This gives a Block of 2405 octets. When reading the Block we find
that there are 3 frames (Octet 4). The data start at Octet 5, so the
size of each frame is (2405 - 5) / 3 = 800.
12.4.5. Laced Frames Timestamp
A Block only contains a single timestamp value. But when lacing is
used, it contains more than one frame. Each frame originally has its
own timestamp, or Presentation Timestamp (PTS). That timestamp
applies to the first frame in the lace.
In the lace, each frame after the first one has an undertermined
timestamp. But each of these frames MUST be contiguous -- i.e. the
decoded data MUST NOT contain any gap between them. If there is a
gap in the stream, the frames around the gap MUST NOT be in the same
Block.
Lacing is only useful for small contiguous data to save space. This
is usually the case for audio tracks and not the case for video --
which use a lot of data -- or subtitle tracks -- which have long
gaps. For audio, there is usually a fixed output sampling frequency
for the whole track. So the decoder should be able to recover the
timestamp of each sample, knowing each output sample is contiguous
with a fixed frequency. For subtitles this is usually not the case
so lacing SHOULD NOT be used.
12.5. Random Access Points
Random Access Points (RAP) are positions where the parser can seek to
and start playback without decoding of what was before. In Matroska
BlockGroups and SimpleBlocks can be RAPs. To seek to these elements
it is still necessary to seek to the Cluster containing them and
start playback from the BlockGroup or SimpleBlock that is a RAP.
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Because a Matroska File is usually composed of multiple tracks
playing at the same time -- video, audio and subtitles -- to seek
properly to a RAP, each selected track must be taken in account.
Usually all audio and subtitle BlockGroup or SimpleBlock are RAP.
They are independent of each other and can be played randomly.
Video tracks on the other hand often use references to previous and
future frames for better coding efficiency. Frames with such
reference MUST either contain one or more ReferenceBlock Elements in
their BlockGroup or MUST be marked as non-keyframe in a SimpleBlock;
see Section 12.3.2.
Frames that are RAP -- i.e. they don't depend on other frames -- MUST
set the keyframe flag if they are in a SimpleBlock or their parent
BlockGroup MUST NOT contain a ReferenceBlock.
There may be cases where the use of BlockGroup is necessary, as the
frame may need a BlockDuration, BlockAdditions, CodecState or a
DiscardPadding element. For thoses cases a SimpleBlock MUST NOT be
used, the reference information SHOULD be recovered for non-RAP
frames.
When a frame in a BlockGroup is not a RAP, all references SHOULD be
listed as a ReferenceBlock, at least some of them, even if not
accurate, or one ReferenceBlock with the value "0" corresponding to a
self or unknown reference. The lack of ReferenceBlock would mean
such a frame is a RAP and seeking on that frame that actually depends
on other frames MAY create bogus output or even crash.
Intra-only video frames, such as the ones found in AV1 or VP9, can be
decoded without any other frame, but they don't reset the codec
state. So seeking to these frames is not possible as the next frames
may need frames that are not known from this seeking point. Such
intra-only frames MUST NOT be considered as keyframes so the keyframe
flag MUST NOT be set in the SimpleBlock or a ReferenceBlock MUST be
used to signify the frame is not a RAP. The timestamp value of the
ReferenceBlock MUST be "0", meaning it's referencing itself.
Because a video SimpleBlock has less references information than a
video BlockGroup, it is possible to remux a video track using
BlockGroup into a SimpleBlock, as long as it doesn't use any other
BlockGroup features than ReferenceBlock.
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13. Timestamps
Historically timestamps in Matroska were mistakenly called timecodes.
The Timestamp Element was called Timecode, the TimestampScale Element
was called TimecodeScale, the TrackTimestampScale Element was called
TrackTimecodeScale and the ReferenceTimestamp Element was called
ReferenceTimeCode.
13.1. Timestamp Ticks
All timestamp values in Matroska are expressed in multiples of a
tick. They are usually stored as integers. There are three types of
ticks possible:
13.1.1. Matroska Ticks
For such elements, the timestamp value is stored directly in
nanoseconds.
The elements storing values in Matroska Ticks/nanoseconds are:
* TrackEntry\DefaultDuration; defined in Section 8.1.4.1.15
* TrackEntry\DefaultDecodedFieldDuration; defined in
Section 8.1.4.1.16
* TrackEntry\SeekPreRoll; defined in Section 8.1.4.1.29
* TrackEntry\CodecDelay; defined in Section 8.1.4.1.28
* BlockGroup\DiscardPadding; defined in Section 8.1.3.5.7
* ChapterAtom\ChapterTimeStart; defined in Section 8.1.7.1.4.3
* ChapterAtom\ChapterTimeEnd; defined in Section 8.1.7.1.4.4
* CuePoint\CueTime; defined in Section 8.1.5.1.1
* CueReference\CueRefTime; defined in Section 8.1.5.1.1
13.1.2. Segment Ticks
Elements in Segment Ticks involve the use of the TimestampScale
Element of the Segment to get the timestamp in nanoseconds of the
element, with the following formula:
timestamp in nanosecond = element value * TimestampScale
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This allows storing smaller integer values in the elements.
When using the default value of TimestampScale of "1,000,000", one
Segment Tick represents one millisecond.
The elements storing values in Segment Ticks are:
* Cluster\Timestamp; defined in Section 8.1.3.1
* Info\Duration is stored as a floating point but the same formula
applies; defined in Section 8.1.2.10
* CuePoint\CueTrackPositions\CueDuration; defined in
Section 8.1.5.1.2.4
13.1.3. Track Ticks
Elements in Segment Ticks involve the use of the TimestampScale
Element of the Segment and the TrackTimestampScale Element of the
Track to get the timestamp in nanoseconds of the element, with the
following formula:
timestamp in nanoseconds =
element value * TrackTimestampScale * TimestampScale
This allows storing smaller integer values in the elements. The
resulting floating point values of the timestamps are still expressed
in nanoseconds.
When using the default values for TimestampScale and
TrackTimestampScale of "1,000,000" and of "1.0" respectively, one
Track Tick represents one millisecond.
The elements storing values in Track Ticks are:
* Cluster\BlockGroup\Block and Cluster\SimpleBlock timestamps;
detailed in Section 13.2
* Cluster\BlockGroup\BlockDuration; defined in Section 8.1.3.5.3
* Cluster\BlockGroup\ReferenceBlock; defined in Section 8.1.3.5.5
When the TrackTimestampScale is interpreted as "1.0", Track Ticks are
equivalent to Segment Ticks and give an integer value in nanoseconds.
This is the most common case as TrackTimestampScale is usually
omitted.
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A value of TrackTimestampScale other than "1.0" MAY be used to scale
the timestamps more in tune with each Track sampling frequency. For
historical reasons, a lot of Matroska readers don't take the
TrackTimestampScale value in account. So using a value other than
"1.0" MAY not work in many places.
13.2. Block Timestamps
A Block Element and SimpleBlock Element timestamp is the time when
the decoded data of the first frame in the Block/SimpleBlock MUST be
presented, if the track of that Block/SimpleBlock is selected for
playback. This is also known as the Presentation Timestamp (PTS).
The Block Element and SimpleBlock Element store their timestamps as
signed integers, relative to the Cluster\Timestamp value of the
Cluster they are stored in. To get the timestamp of a Block or
SimpleBlock in nanoseconds you have to use the following formula:
( Cluster\Timestamp + ( block timestamp * TrackTimestampScale ) ) *
TimestampScale
The Block Element and SimpleBlock Element store their timestamps as
16bit signed integers, allowing a range from "-32768" to "+32767"
Track Ticks. Although these values can be negative, when added to
the Cluster\Timestamp, the resulting frame timestamp SHOULD NOT be
negative.
When a CodecDelay Element is set, its value MUST be substracted from
each Block timestamp of that track. To get the timestamp in
nanoseconds of the first frame in a Block or SimpleBlock, the formula
becomes:
( ( Cluster\Timestamp + ( block timestamp * TrackTimestampScale ) ) *
TimestampScale ) - CodecDelay
The resulting frame timestamp SHOULD NOT be negative.
During playback, when a frame has a negative timestamp, the content
MUST be decoded by the decoder but not played to the user.
13.3. TimestampScale Rounding
The default Track Tick duration is one millisecond.
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The TimestampScale is a floating value, which is usually 1.0. But
when it's not, the multiplied Block Timestamp is a floating values in
nanoseconds. The Matroska Reader SHOULD use the nearest rounding
value in nanosecond to get the proper nanosecond timestamp of a
Block. This allows some clever TimestampScale values to have more
refined timestampt precision per frame.
14. Encryption
Encryption in Matroska is designed in a very generic style to allow
people to implement whatever form of encryption is best for them. It
is possible to use the encryption framework in Matroska as a type of
DRM (Digital Rights Management).
Because encryption occurs within the Block Element, it is possible to
manipulate encrypted streams without decrypting them. The streams
could potentially be copied, deleted, cut, appended, or any number of
other possible editing techniques without decryption. The data can
be used without having to expose it or go through the decrypting
process.
Encryption can also be layered within Matroska. This means that two
completely different types of encryption can be used, requiring two
separate keys to be able to decrypt a stream.
Encryption information is stored in the ContentEncodings Element
under the ContentEncryption Element.
15. Image Presentation
15.1. Cropping
The PixelCrop Elements (PixelCropTop, PixelCropBottom,
PixelCropRight, and PixelCropLeft) indicate when, and by how much,
encoded videos frames SHOULD be cropped for display. These Elements
allow edges of the frame that are not intended for display, such as
the sprockets of a full-frame film scan or the VANC area of a
digitized analog videotape, to be stored but hidden. PixelCropTop
and PixelCropBottom store an integer of how many rows of pixels
SHOULD be cropped from the top and bottom of the image
(respectively). PixelCropLeft and PixelCropRight store an integer of
how many columns of pixels SHOULD be cropped from the left and right
of the image (respectively). For example, a pillar-boxed video that
stores a 1440x1080 visual image within the center of a padded
1920x1080 encoded image MAY set both PixelCropLeft and PixelCropRight
to "240", so that a Matroska Player SHOULD crop off 240 columns of
pixels from the left and right of the encoded image to present the
image with the pillar-boxes hidden.
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Cropping has to be performed before resizing and the display
dimensions given by DisplayWidth, DisplayHeight and DisplayUnit apply
to the already cropped image.
15.2. Rotation
The ProjectionPoseRoll Element (see Section 8.1.4.1.31.45) can be
used to indicate that the image from the associated video track
SHOULD be rotated for presentation. For instance, the following
representation of the Projection Element Section 8.1.4.1.31.40) and
the ProjectionPoseRoll Element represents a video track where the
image SHOULD be presentation with a 90 degree counter-clockwise
rotation.
<Projection>
<ProjectionPoseRoll>90</ProjectionPoseRoll>
</Projection>
Figure 11: Rotation example.
16. Matroska versioning
The EBML Header of each Matroska document informs the reading
application on what version of Matroska to expect. The Elements
within EBML Header with jurisdiction over this information are
DocTypeVersion and DocTypeReadVersion.
DocTypeVersion MUST be equal to or greater than the highest Matroska
version number of any Element present in the Matroska file. For
example, a file using the SimpleBlock Element MUST have a
DocTypeVersion equal to or greater than 2. A file containing
CueRelativePosition Elements MUST have a DocTypeVersion equal to or
greater than 4.
The DocTypeReadVersion MUST contain the minimum version number that a
reading application can minimally support in order to play the file
back -- optionally with a reduced feature set. For example, if a
file contains only Elements of version 2 or lower except for
CueRelativePosition (which is a version 4 Matroska Element), then
DocTypeReadVersion SHOULD still be set to 2 and not 4 because
evaluating CueRelativePosition is not necessary for standard playback
-- it makes seeking more precise if used.
DocTypeVersion MUST always be equal to or greater than
DocTypeReadVersion.
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A reading application supporting Matroska version V MUST NOT refuse
to read an application with DocReadTypeVersion equal to or lower than
V even if DocTypeVersion is greater than V. See also the note about
Unknown Elements in Section 10.
17. File Extensions
The file extensions for Matroska files are usually as follows:
* ".mkv" for files containing video tracks
* ".mka" for files containing audio tracks with no video tracks
* ".mk3d" for files containing some stereoscopic video tracks
18. Segment Position
The Segment Position of an Element refers to the position of the
first octet of the Element ID of that Element, measured in octets,
from the beginning of the Element Data section of the containing
Segment Element. In other words, the Segment Position of an Element
is the distance in octets from the beginning of its containing
Segment Element minus the size of the Element ID and Element Data
Size of that Segment Element. The Segment Position of the first
Child Element of the Segment Element is 0. An Element which is not
stored within a Segment Element, such as the Elements of the EBML
Header, do not have a Segment Position.
18.1. Segment Position Exception
Elements that are defined to store a Segment Position MAY define
reserved values to indicate a special meaning.
18.2. Example of Segment Position
This table presents an example of Segment Position by showing a
hexadecimal representation of a very small Matroska file with labels
to show the offsets in octets. The file contains a Segment Element
with an Element ID of "0x18538067" and a MuxingApp Element with an
Element ID of "0x4D80".
0 1 2
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
0 |1A|45|DF|A3|8B|42|82|88|6D|61|74|72|6F|73|6B|61|18|53|80|67|
20 |93|15|49|A9|66|8E|4D|80|84|69|65|74|66|57|41|84|69|65|74|66|
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In the above example, the Element ID of the Segment Element is stored
at offset 16, the Element Data Size of the Segment Element is stored
at offset 20, and the Element Data of the Segment Element is stored
at offset 21.
The MuxingApp Element is stored at offset 26. Since the Segment
Position of an Element is calculated by subtracting the position of
the Element Data of the containing Segment Element from the position
of that Element, the Segment Position of MuxingApp Element in the
above example is '26 - 21' or '5'.
19. Linked Segments
Matroska provides several methods to link two or more Segment
Elements together to create a Linked Segment. A Linked Segment is a
set of multiple Segments linked together into a single presentation
by using Hard Linking or Medium Linking.
All Segments within a Linked Segment MUST have a SegmentUID.
All Segments within a Linked Segment SHOULD be stored within the same
directory or be accessible quickly based on their SegmentUID in order
to have seamless transition between segments.
All Segments within a Linked Segment MAY set a SegmentFamily with a
common value to make it easier for a Matroska Player to know which
Segments are meant to be played together.
The SegmentFilename, PrevFilename and NextFilename elements MAY also
give hints on the original filenames that were used when the Segment
links were created, in case some SegmentUID are damaged.
19.1. Hard Linking
Hard Linking, also called splitting, is the process of creating a
Linked Segment by linking multiple Segment Elements using the NextUID
and PrevUID Elements.
All Segments within a Hard Linked Segment MUST use the same Tracks
list and TimestampScale.
Within a Linked Segment, the timestamps of Block and SimpleBlock MUST
follow consecutively the timestamps of Block and SimpleBlock from the
previous Segment in linking order.
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With Hard Linking, the chapters of any Segment within the Linked
Segment MUST only reference the current Segment. The NextUID and
PrevUID reference the respective SegmentUID values of the next and
previous Segments.
The first Segment of a Linked Segment MUST NOT have a PrevUID
Element. The last Segment of a Linked Segment MUST NOT have a
NextUID Element.
For each node of the chain of Segments of a Linked Segment at least
one Segment MUST reference the other Segment of the node.
In a chain of Segments of a Linked Segment the NextUID always takes
precedence over the PrevUID. So if SegmentA has a NextUID to
SegmentB and SegmentB has a PrevUID to SegmentC, the link to use is
NextUID between SegmentA and SegmentB, SegmentC is not part of the
Linked Segment.
If SegmentB has a PrevUID to SegmentA but SegmentA has no NextUID,
then the Matroska Player MAY consider these two Segments linked as
SegmentA followed by SegmentB.
As an example, three Segments can be Hard Linked as a Linked Segment
through cross-referencing each other with SegmentUID, PrevUID, and
NextUID, as in this table:
+==========+==================+==================+==================+
|file name | SegmentUID | PrevUID | NextUID |
+==========+==================+==================+==================+
|start.mkv | 71000c23cd310998 | Invalid | a77b3598941cb803 |
| | 53fbc94dd984a5dd | | eac0fcdafe44fac9 |
+----------+------------------+------------------+------------------+
|middle.mkv| a77b3598941cb803 | 71000c23cd310998 | 6c92285fa6d3e827 |
| | eac0fcdafe44fac9 | 53fbc94dd984a5dd | b198d120ea3ac674 |
+----------+------------------+------------------+------------------+
|end.mkv | 6c92285fa6d3e827 | a77b3598941cb803 | Invalid |
| | b198d120ea3ac674 | eac0fcdafe44fac9 | |
+----------+------------------+------------------+------------------+
Table 42: Usual Hard Linking UIDs
An other example where only the NextUID Element is used:
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+============+==================+=========+==================+
| file name | SegmentUID | PrevUID | NextUID |
+============+==================+=========+==================+
| start.mkv | 71000c23cd310998 | Invalid | a77b3598941cb803 |
| | 53fbc94dd984a5dd | | eac0fcdafe44fac9 |
+------------+------------------+---------+------------------+
| middle.mkv | a77b3598941cb803 | n/a | 6c92285fa6d3e827 |
| | eac0fcdafe44fac9 | | b198d120ea3ac674 |
+------------+------------------+---------+------------------+
| end.mkv | 6c92285fa6d3e827 | n/a | Invalid |
| | b198d120ea3ac674 | | |
+------------+------------------+---------+------------------+
Table 43: Hard Linking without PrevUID
An example where only the PrevUID Element is used:
+============+==================+==================+=========+
| file name | SegmentUID | PrevUID | NextUID |
+============+==================+==================+=========+
| start.mkv | 71000c23cd310998 | Invalid | n/a |
| | 53fbc94dd984a5dd | | |
+------------+------------------+------------------+---------+
| middle.mkv | a77b3598941cb803 | 71000c23cd310998 | n/a |
| | eac0fcdafe44fac9 | 53fbc94dd984a5dd | |
+------------+------------------+------------------+---------+
| end.mkv | 6c92285fa6d3e827 | a77b3598941cb803 | Invalid |
| | b198d120ea3ac674 | eac0fcdafe44fac9 | |
+------------+------------------+------------------+---------+
Table 44: Hard Linking without NextUID
In this example only the middle.mkv is using the PrevUID and NextUID
Elements:
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+==========+==================+==================+==================+
|file name | SegmentUID | PrevUID | NextUID |
+==========+==================+==================+==================+
|start.mkv | 71000c23cd310998 | Invalid | n/a |
| | 53fbc94dd984a5dd | | |
+----------+------------------+------------------+------------------+
|middle.mkv| a77b3598941cb803 | 71000c23cd310998 | 6c92285fa6d3e827 |
| | eac0fcdafe44fac9 | 53fbc94dd984a5dd | b198d120ea3ac674 |
+----------+------------------+------------------+------------------+
|end.mkv | 6c92285fa6d3e827 | n/a | Invalid |
| | b198d120ea3ac674 | | |
+----------+------------------+------------------+------------------+
Table 45: Hard Linking with mixed UID links
19.2. Medium Linking
Medium Linking creates relationships between Segments using Ordered
Chapters (Section 22.1.3) and the ChapterSegmentUID Element. A
Chapter Edition with Ordered Chapters MAY contain Chapter elements
that reference timestamp ranges from other Segments. The Segment
referenced by the Ordered Chapter via the ChapterSegmentUID Element
SHOULD be played as part of a Linked Segment.
The timestamps of Segment content referenced by Ordered Chapters MUST
be adjusted according to the cumulative duration of the the previous
Ordered Chapters.
As an example a file named intro.mkv could have a SegmentUID of
"0xb16a58609fc7e60653a60c984fc11ead". Another file called
program.mkv could use a Chapter Edition that contains two Ordered
Chapters. The first chapter references the Segment of intro.mkv with
the use of a ChapterSegmentUID, ChapterSegmentEditionUID,
ChapterTimeStart, and optionally a ChapterTimeEnd element. The
second chapter references content within the Segment of program.mkv.
A Matroska Player SHOULD recognize the Linked Segment created by the
use of ChapterSegmentUID in an enabled Edition and present the
reference content of the two Segments as a single presentation.
The ChapterSegmentUID represents the Segment that holds the content
to play in place of the Linked Chapter. The ChapterSegmentUID MUST
NOT be the SegmentUID of its own Segment.
There are 2 ways to use a chapter link: * Linked-Duration linking, *
Linked-Edition linking
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19.2.1. Linked-Duration
A Matroska Player MUST play the content of the linked Segment from
the ChapterTimeStart until ChapterTimeEnd timestamp in place of the
Linked Chapter.
ChapterTimeStart and ChapterTimeEnd represent timestamps in the
Linked Segment matching the value of ChapterSegmentUID. Their values
MUST be in the range of the linked Segment duration.
The ChapterTimeEnd value MUST be set when using linked-duration
chapter linking. ChapterSegmentEditionUID MUST NOT be set.
19.2.2. Linked-Edition
A Matroska Player MUST play the whole linked Edition of the linked
Segment in place of the Linked Chapter.
ChapterSegmentEditionUID represents a valid Edition from the Linked
Segment matching the value of ChapterSegmentUID.
When using linked-edition chapter linking. ChapterTimeEnd is
OPTIONAL.
20. Track Flags
20.1. Default flag
The "default track" flag is a hint for a Matroska Player indicating
that a given track SHOULD be eligible to be automatically selected as
the default track for a given language. If no tracks in a given
language have the default track flag set, then all tracks in that
language are eligible for automatic selection. This can be used to
indicate that a track provides "regular service" suitable for users
with default settings, as opposed to specialized services, such as
commentary, hearing-impaired captions, or descriptive audio.
The Matroska Player MAY override the "default track" flag for any
reason, including user preferences to prefer tracks providing
accessibility services.
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20.2. Forced flag
The "forced" flag tells the Matroska Player that it SHOULD display
this subtitle track, even if user preferences usually would not call
for any subtitles to be displayed alongside the current selected
audio track. This can be used to indicate that a track contains
translations of onscreen text, or of dialogue spoken in a different
language than the track's primary one.
20.3. Hearing-impaired flag
The "hearing impaired" flag tells the Matroska Player that it SHOULD
prefer this track when selecting a default track for a hearing-
impaired user, and that it MAY prefer to select a different track
when selecting a default track for a non-hearing-impaired user.
20.4. Visual-impaired flag
The "visual impaired" flag tells the Matroska Player that it SHOULD
prefer this track when selecting a default track for a visually-
impaired user, and that it MAY prefer to select a different track
when selecting a default track for a non-visually-impaired user.
20.5. Descriptions flag
The "descriptions" flag tells the Matroska Player that this track is
suitable to play via a text-to-speech system for a visually-impaired
user, and that it SHOULD NOT automatically select this track when
selecting a default track for a non-visually-impaired user.
20.6. Original flag
The "original" flag tells the Matroska Player that this track is in
the original language, and that it SHOULD prefer it if configured to
prefer original-language tracks of this track's type.
20.7. Commentary flag
The "commentary" flag tells the Matroska Player that this track
contains commentary on the content.
20.8. Track Operation
TrackOperation allows combining multiple tracks to make a virtual
one. It uses two separate system to combine tracks. One to create a
3D "composition" (left/right/background planes) and one to simplify
join two tracks together to make a single track.
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A track created with TrackOperation is a proper track with a UID and
all its flags. However the codec ID is meaningless because each
"sub" track needs to be decoded by its own decoder before the
"operation" is applied. The Cues Elements corresponding to such a
virtual track SHOULD be the sum of the Cues Elements for each of the
tracks it's composed of (when the Cues are defined per track).
In the case of TrackJoinBlocks, the Block Elements (from BlockGroup
and SimpleBlock) of all the tracks SHOULD be used as if they were
defined for this new virtual Track. When two Block Elements have
overlapping start or end timestamps, it's up to the underlying system
to either drop some of these frames or render them the way they
overlap. This situation SHOULD be avoided when creating such tracks
as you can never be sure of the end result on different platforms.
20.9. Overlay Track
Overlay tracks SHOULD be rendered in the same channel as the track
its linked to. When content is found in such a track, it SHOULD be
played on the rendering channel instead of the original track.
20.10. Multi-planar and 3D videos
There are two different ways to compress 3D videos: have each eye
track in a separate track and have one track have both eyes combined
inside (which is more efficient, compression-wise). Matroska
supports both ways.
For the single track variant, there is the StereoMode Element, which
defines how planes are assembled in the track (mono or left-right
combined). Odd values of StereoMode means the left plane comes first
for more convenient reading. The pixel count of the track
(PixelWidth/PixelHeight) is the raw amount of pixels, for example
3840x1080 for full HD side by side, and the DisplayWidth/
DisplayHeight in pixels is the amount of pixels for one plane
(1920x1080 for that full HD stream). Old stereo 3D were displayed
using anaglyph (cyan and red colors separated). For compatibility
with such movies, there is a value of the StereoMode that corresponds
to AnaGlyph.
There is also a "packed" mode (values 13 and 14) which consists of
packing two frames together in a Block using lacing. The first frame
is the left eye and the other frame is the right eye (or vice versa).
The frames SHOULD be decoded in that order and are possibly dependent
on each other (P and B frames).
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For separate tracks, Matroska needs to define exactly which track
does what. TrackOperation with TrackCombinePlanes do that. For more
details look at Section 20.8 on how TrackOperation works.
The 3D support is still in infancy and may evolve to support more
features.
The StereoMode used to be part of Matroska v2 but it didn't meet the
requirement for multiple tracks. There was also a bug in libmatroska
prior to 0.9.0 that would save/read it as 0x53B9 instead of 0x53B8.
Matroska Readers may support these legacy files by checking Matroska
v2 or 0x53B9. The older values were 0: mono, 1: right eye, 2: left
eye, 3: both eyes.
21. Default track selection
This section provides some example sets of Tracks and hypothetical
user settings, along with indications of which ones a similarly-
configured Matroska Player SHOULD automatically select for playback
by default in such a situation. A player MAY provide additional
settings with more detailed controls for more nuanced scenarios.
These examples are provided as guidelines to illustrate the intended
usages of the various supported Track flags, and their expected
behaviors.
Track names are shown in English for illustrative purposes; actual
files may have titles in the language of each track, or provide
titles in multiple languages.
21.1. Audio Selection
Example track set:
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+===+=====+====+======+========+=======+================+===========+
|No.|Type |Lang|Layout|Original|Default|Other flags |Name |
+===+=====+====+======+========+=======+================+===========+
|1 |Video|und |N/A |N/A |N/A |None | |
+---+-----+----+------+--------+-------+----------------+-----------+
|2 |Audio|eng |5.1 |1 |1 |None | |
+---+-----+----+------+--------+-------+----------------+-----------+
|3 |Audio|eng |2.0 |1 |1 |None | |
+---+-----+----+------+--------+-------+----------------+-----------+
|4 |Audio|eng |2.0 |1 |0 |Visual-impaired |Descriptive|
| | | | | | | |audio |
+---+-----+----+------+--------+-------+----------------+-----------+
|5 |Audio|esp |5.1 |0 |1 |None | |
+---+-----+----+------+--------+-------+----------------+-----------+
|6 |Audio|esp |2.0 |0 |0 |Visual-impaired |Descriptive|
| | | | | | | |audio |
+---+-----+----+------+--------+-------+----------------+-----------+
|7 |Audio|eng |2.0 |1 |0 |Commentary |Director's |
| | | | | | | |Commentary |
+---+-----+----+------+--------+-------+----------------+-----------+
|8 |Audio|eng |2.0 |1 |0 |None |Karaoke |
+---+-----+----+------+--------+-------+----------------+-----------+
Table 46: Audio Tracks for default selection
Here we have a file with 7 audio tracks, of which 5 are in English
and 2 are in Spanish.
The English tracks all have the Original flag, indicating that
English is the original content language.
Generally the player will first consider the track languages: if the
player has an option to prefer original-language audio and the user
has enabled it, then it should prefer one of the Original-flagged
tracks. If configured to specifically prefer audio tracks in English
or Spanish, the player should select one of the tracks in the
corresponding language. The player may also wish to prefer an
Original-flagged track if no tracks matching any of the user's
explicitly-preferred languages are available.
Two of the tracks have the Visual-impaired flag. If the player has
been configured to prefer such tracks, it should select one;
otherwise, it should avoid them if possible.
If selecting an English track, when other settings have left multiple
possible options, it may be useful to exclude the tracks that lack
the Default flag: here, one provides descriptive service for the
visually impaired (which has its own flag and may be automatically
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selected by user configuration, but is unsuitable for users with
default-configured players), one is a commentary track (which has its
own flag, which the player may or may not have specialized handling
for), and the last contains karaoke versions of the music that plays
during the film, which is an unusual specialized audio service that
Matroska has no built-in support for indicating, so it's indicated in
the track name instead. By not setting the Default flag on these
specialized tracks, the file's author hints that they should not be
automatically selected by a default-configured player.
Having narrowed its choices down, our example player now may have to
select between tracks 2 and 3. The only difference between these
tracks is their channel layouts: 2 is 5.1 surround, while 3 is
stereo. If the player is aware that the output device is a pair of
headphones or stereo speakers, it may wish to prefer the stereo mix
automatically. On the other hand, if it knows that the device is a
surround system, it may wish to prefer the surround mix.
If the player finishes analyzing all of the available audio tracks
and finds that multiple seem equally and maximally preferable, it
SHOULD default to the first of the group.
21.2. Subtitle selection
Example track set:
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+===+===========+====+=========+=======+======+==========+==========+
|No.| Type |Lang|Original |Default|Forced| Other | Name |
| | | | | | | flags | |
+===+===========+====+=========+=======+======+==========+==========+
|1 | Video |und |N/A |N/A |N/A | None | |
+---+-----------+----+---------+-------+------+----------+----------+
|2 | Audio |fra |1 |1 |N/A | None | |
+---+-----------+----+---------+-------+------+----------+----------+
|3 | Audio |por |0 |1 |N/A | None | |
+---+-----------+----+---------+-------+------+----------+----------+
|4 | Subtitles |fra |1 |1 |0 | None | |
+---+-----------+----+---------+-------+------+----------+----------+
|5 | Subtitles |fra |1 |0 |0 | Hearing- | Captions |
| | | | | | | impaired | for the |
| | | | | | | | hearing- |
| | | | | | | | impaired |
+---+-----------+----+---------+-------+------+----------+----------+
|6 | Subtitles |por |0 |1 |0 | None | |
+---+-----------+----+---------+-------+------+----------+----------+
|7 | Subtitles |por |0 |0 |1 | None | Signs |
+---+-----------+----+---------+-------+------+----------+----------+
|8 | Subtitles |por |0 |0 |0 | Hearing- | SDH |
| | | | | | | impaired | |
+---+-----------+----+---------+-------+------+----------+----------+
Table 47: Subtitle Tracks for default selection
Here we have 2 audio tracks and 5 subtitle tracks. As we can see,
French is the original language.
We'll start by discussing the case where the user prefers French (or
Original-language) audio (or has explicitly selected the French audio
track), and also prefers French subtitles.
In this case, if the player isn't configured to display captions when
the audio matches their preferred subtitle languages, the player
doesn't need to select a subtitle track at all.
If the user _has_ indicated that they want captions to be displayed,
the selection simply comes down to whether Hearing-impaired subtitles
are preferred.
The situation for a user who prefers Portuguese subtitles starts out
somewhat analogous. If they select the original French audio (either
by explicit audio language preference, preference for Original-
language tracks, or by explicitly selecting that track), then the
selection once again comes down to the hearing-impaired preference.
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However, the case where the Portuguese audio track is selected has an
important catch: a Forced track in Portuguese is present. This may
contain translations of onscreen text from the video track, or of
portions of the audio that are not translated (music, for instance).
This means that even if the user's preferences wouldn't normally call
for captions here, the Forced track should be selected nonetheless,
rather than selecting no track at all. On the other hand, if the
user's preferences _do_ call for captions, the non-Forced tracks
should be preferred, as the Forced track will not contain captioning
for the dialogue.
22. Chapters
The Matroska Chapters system can have multiple Editions and each
Edition can consist of Simple Chapters where a chapter start time is
used as marker in the timeline only. An Edition can be more complex
with Ordered Chapters where a chapter end time stamp is additionally
used or much more complex with Linked Chapters. The Matroska
Chapters system can also have a menu structure, borrowed from the DVD
menu system, or have it's own Native Matroska menu structure.
22.1. EditionEntry
The EditionEntry is also called an Edition. An Edition contains a
set of Edition flags and MUST contain at least one ChapterAtom
Element. Chapters are always inside an Edition (or a Chapter itself
part of an Edition). Multiple Editions are allowed. Some of these
Editions MAY be ordered and others not.
22.1.1. EditionFlagDefault
Only one Edition SHOULD have an EditionFlagDefault flag set to true.
22.1.2. Default Edition
The Default Edition is the Edition that a Matroska Player SHOULD use
for playback by default.
The first Edition with the EditionFlagDefault flag set to true is the
Default Edition.
When all EditionFlagDefault flags are set to false, then the first
Edition is the Default Edition.
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+===========+=============+=================+
| Edition | FlagDefault | Default Edition |
+===========+=============+=================+
| Edition 1 | true | X |
+-----------+-------------+-----------------+
| Edition 2 | true | |
+-----------+-------------+-----------------+
| Edition 3 | true | |
+-----------+-------------+-----------------+
Table 48: Default edition, all default
+===========+=============+=================+
| Edition | FlagDefault | Default Edition |
+===========+=============+=================+
| Edition 1 | false | X |
+-----------+-------------+-----------------+
| Edition 2 | false | |
+-----------+-------------+-----------------+
| Edition 3 | false | |
+-----------+-------------+-----------------+
Table 49: Default edition, no default
+===========+=============+=================+
| Edition | FlagDefault | Default Edition |
+===========+=============+=================+
| Edition 1 | false | |
+-----------+-------------+-----------------+
| Edition 2 | true | X |
+-----------+-------------+-----------------+
| Edition 3 | false | |
+-----------+-------------+-----------------+
Table 50: Default edition, with default
22.1.3. EditionFlagOrdered
The EditionFlagOrdered Flag is a significant feature as it enables an
Edition of Ordered Chapters which defines and arranges a virtual
timeline rather than simply labeling points within the timeline. For
example, with Editions of Ordered Chapters a single Matroska file can
present multiple edits of a film without duplicating content.
Alternatively, if a videotape is digitized in full, one Ordered
Edition could present the full content (including colorbars,
countdown, slate, a feature presentation, and black frames), while
another Edition of Ordered Chapters can use Chapters that only mark
the intended presentation with the colorbars and other ancillary
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visual information excluded. If an Edition of Ordered Chapters is
enabled, then the Matroska Player MUST play those Chapters in their
stored order from the timestamp marked in the ChapterTimeStart
Element to the timestamp marked in to ChapterTimeEnd Element.
If the EditionFlagOrdered Flag evaluates to "0", Simple Chapters are
used and only the ChapterTimeStart of a Chapter is used as chapter
mark to jump to the predefined point in the timeline. With Simple
Chapters, a Matroska Player MUST ignore certain Chapter Elements. In
that case these elements are informational only.
The following list shows the different Chapter elements only found in
Ordered Chapters.
+======================================+
| Ordered Chapter elements |
+======================================+
| ChapterAtom/ChapterSegmentUID |
+--------------------------------------+
| ChapterAtom/ChapterSegmentEditionUID |
+--------------------------------------+
| ChapterAtom/ChapterTrack |
+--------------------------------------+
| ChapterAtom/ChapProcess |
+--------------------------------------+
| Info/ChapterTranslate |
+--------------------------------------+
| TrackEntry/TrackTranslate |
+--------------------------------------+
Table 51: elements only found in
ordered chapters
Furthermore there are other EBML Elements which could be used if the
EditionFlagOrdered evaluates to "1".
22.1.3.1. Ordered-Edition and Matroska Segment-Linking
* Hard Linking: Ordered-Chapters supersedes the Hard Linking.
* Medium Linking: Ordered Chapters are used in a normal way and can
be combined with the ChapterSegmentUID element which establishes a
link to another Segment.
See Section 19 on the Linked Segments for more information about Hard
Linking and Medium Linking.
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22.2. ChapterAtom
The ChapterAtom is also called a Chapter.
22.2.1. ChapterTimeStart
The timestamp of the start of Chapter with nanosecond accuracy, not
scaled by TimestampScale. For Simple Chapters this is the position
of the chapter markers in the timeline.
22.2.2. ChapterTimeEnd
The timestamp of the end of Chapter with nanosecond accuracy, not
scaled by TimestampScale. The timestamp defined by the
ChapterTimeEnd is not part of the Chapter. A Matroska Player
calculates the duration of this Chapter using the difference between
the ChapterTimeEnd and ChapterTimeStart. The end timestamp MUST be
greater than or equal to the start timestamp.
When the ChapterTimeEnd timestamp is equal to the ChapterTimeStart
timestamp, the timestamps is included in the Chapter. It can be
useful to put markers in a file or add chapter commands with ordered
chapter commands without having to play anything; see
Section 8.1.7.1.4.14.
+===========+=================+===============+===============+
| Chapter | Start timestamp | End timestamp | Duration |
+===========+=================+===============+===============+
| Chapter 1 | 0 | 1000000000 | 1000000000 |
+-----------+-----------------+---------------+---------------+
| Chapter 2 | 1000000000 | 5000000000 | 4000000000 |
+-----------+-----------------+---------------+---------------+
| Chapter 3 | 6000000000 | 6000000000 | 0 |
+-----------+-----------------+---------------+---------------+
| Chapter 4 | 9000000000 | 8000000000 | Invalid |
| | | | (-1000000000) |
+-----------+-----------------+---------------+---------------+
Table 52: ChapterTimeEnd usage possibilities
22.2.3. Nested Chapters
A ChapterAtom element can contain other ChapterAtom elements. That
element is a Parent Chapter and the ChapterAtom elements it contains
are Nested Chapters.
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Nested Chapters can be useful to tag small parts of a Segment that
already have tags or add Chapter Codec commands on smaller parts of a
Segment that already have Chapter Codec commands.
The ChapterTimeStart of a Nested Chapter MUST be greater than or
equal to the ChapterTimeStart its Parent Chapter.
If the Parent Chapter of a Nested Chapter has a ChapterTimeEnd, the
ChapterTimeStart of that Nested Chapter MUST be smaller than or equal
to the ChapterTimeEnd of the Parent Chapter.
22.2.4. Nested Chapters in Ordered Chapters
The ChapterTimeEnd of the lowest level of Nested Chapters MUST be set
for Ordered Chapters.
When used with Ordered Chapters, the ChapterTimeEnd value of a Parent
Chapter is useless for playback as the proper playback sections are
described in its Nested Chapters. The ChapterTimeEnd SHOULD NOT be
set in Parent Chapters and MUST be ignored for playback.
22.2.5. ChapterFlagHidden
Each Chapter ChapterFlagHidden flag works independently from parent
chapters. A Nested Chapter with a ChapterFlagHidden that evaluates
to "0" remains visible in the user interface even if the Parent
Chapter ChapterFlagHidden flag is set to "1".
+==========================+===================+=========+
| Chapter + Nested Chapter | ChapterFlagHidden | visible |
+==========================+===================+=========+
| Chapter 1 | 0 | yes |
+--------------------------+-------------------+---------+
| Nested Chapter 1.1 | 0 | yes |
+--------------------------+-------------------+---------+
| Nested Chapter 1.2 | 1 | no |
+--------------------------+-------------------+---------+
| Chapter 2 | 1 | no |
+--------------------------+-------------------+---------+
| Nested Chapter 2.1 | 0 | yes |
+--------------------------+-------------------+---------+
| Nested Chapter 2.2 | 1 | no |
+--------------------------+-------------------+---------+
Table 53: ChapterFlagHidden nested visibility
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22.3. Menu features
The menu features are handled like a chapter codec. That means each
codec has a type, some private data and some data in the chapters.
The type of the menu system is defined by the ChapProcessCodecID
parameter. For now, only 2 values are supported : 0 matroska script,
1 menu borrowed from the DVD. The private data depend on the type of
menu system (stored in ChapProcessPrivate), idem for the data in the
chapters (stored in ChapProcessData).
The menu system, as well a Chapter Codecs in general, can do actions
on the Matroska Player like jumping to another Chapter or Edition,
selecting different tracks and possibly more. The scope of all the
possibilities of Chapter Codecs is not covered in this document as it
depends on the Chapter Codec features and its integration in a
Matroska Player.
22.4. Physical Types
Each level can have different meanings for audio and video. The
ORIGINAL_MEDIUM tag can be used to specify a string for
ChapterPhysicalEquiv = 60. Here is the list of possible levels for
both audio and video:
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+=======+=======================+=============+=====================+
| Value | Audio | Video | Comment |
+=======+=======================+=============+=====================+
| 70 | SET / PACKAGE | SET / | the collection of |
| | | PACKAGE | different media |
+-------+-----------------------+-------------+---------------------+
| 60 | CD / 12" / 10" / 7" / | DVD / VHS | the physical medium |
| | TAPE / MINIDISC / DAT | / | like a CD or a DVD |
| | | LASERDISC | |
+-------+-----------------------+-------------+---------------------+
| 50 | SIDE | SIDE | when the original |
| | | | medium (LP/DVD) has |
| | | | different sides |
+-------+-----------------------+-------------+---------------------+
| 40 | - | LAYER | another physical |
| | | | level on DVDs |
+-------+-----------------------+-------------+---------------------+
| 30 | SESSION | SESSION | as found on CDs and |
| | | | DVDs |
+-------+-----------------------+-------------+---------------------+
| 20 | TRACK | - | as found on audio |
| | | | CDs |
+-------+-----------------------+-------------+---------------------+
| 10 | INDEX | - | the first logical |
| | | | level of the side/ |
| | | | medium |
+-------+-----------------------+-------------+---------------------+
Table 54: ChapterPhysicalEquiv meaning per track type
22.5. Chapter Examples
22.5.1. Example 1 : basic chaptering
In this example a movie is split in different chapters. It could
also just be an audio file (album) on which each track corresponds to
a chapter.
* 00000ms - 05000ms : Intro
* 05000ms - 25000ms : Before the crime
* 25000ms - 27500ms : The crime
* 27500ms - 38000ms : The killer arrested
* 38000ms - 43000ms : Credits
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This would translate in the following matroska form :
<Chapters>
<EditionEntry>
<EditionUID>16603393396715046047</EditionUID>
<ChapterAtom>
<ChapterUID>1193046</ChapterUID>
<ChapterTimeStart>0</ChapterTimeStart>
<ChapterTimeEnd>5000000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Intro</ChapString>
</ChapterDisplay>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>2311527</ChapterUID>
<ChapterTimeStart>5000000000</ChapterTimeStart>
<ChapterTimeEnd>25000000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Before the crime</ChapString>
</ChapterDisplay>
<ChapterDisplay>
<ChapString>Avant le crime</ChapString>
<ChapLanguage>fra</ChapLanguage>
</ChapterDisplay>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>3430008</ChapterUID>
<ChapterTimeStart>25000000000</ChapterTimeStart>
<ChapterTimeEnd>27500000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>The crime</ChapString>
</ChapterDisplay>
<ChapterDisplay>
<ChapString>Le crime</ChapString>
<ChapLanguage>fra</ChapLanguage>
</ChapterDisplay>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>4548489</ChapterUID>
<ChapterTimeStart>27500000000</ChapterTimeStart>
<ChapterTimeEnd>38000000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>After the crime</ChapString>
</ChapterDisplay>
<ChapterDisplay>
<ChapString>Après le crime</ChapString>
<ChapLanguage>fra</ChapLanguage>
</ChapterDisplay>
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</ChapterAtom>
<ChapterAtom>
<ChapterUID>5666960</ChapterUID>
<ChapterTimeStart>38000000000</ChapterTimeStart>
<ChapterTimeEnd>43000000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Credits</ChapString>
</ChapterDisplay>
<ChapterDisplay>
<ChapString>Générique</ChapString>
<ChapLanguage>fra</ChapLanguage>
</ChapterDisplay>
</ChapterAtom>
</EditionEntry>
</Chapters>
Figure 12: Basic Chapters Example.
22.5.2. Example 2 : nested chapters
In this example an (existing) album is split into different chapters,
and one of them contain another splitting.
22.5.2.1. The Micronauts "Bleep To Bleep"
* 00:00 - 12:28 : Baby Wants To Bleep/Rock
- 00:00 - 04:38 : Baby wants to bleep (pt.1)
- 04:38 - 07:12 : Baby wants to rock
- 07:12 - 10:33 : Baby wants to bleep (pt.2)
- 10:33 - 12:28 : Baby wants to bleep (pt.3)
* 12:30 - 19:38 : Bleeper_O+2
* 19:40 - 22:20 : Baby wants to bleep (pt.4)
* 22:22 - 25:18 : Bleep to bleep
* 25:20 - 33:35 : Baby wants to bleep (k)
* 33:37 - 44:28 : Bleeper
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<Chapters>
<EditionEntry>
<EditionUID>1281690858003401414</EditionUID>
<ChapterAtom>
<ChapterUID>1</ChapterUID>
<ChapterTimeStart>0</ChapterTimeStart>
<ChapterTimeEnd>748000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Baby wants to Bleep/Rock</ChapString>
</ChapterDisplay>
<ChapterAtom>
<ChapterUID>2</ChapterUID>
<ChapterTimeStart>0</ChapterTimeStart>
<ChapterTimeEnd>278000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Baby wants to bleep (pt.1)</ChapString>
</ChapterDisplay>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>3</ChapterUID>
<ChapterTimeStart>278000000</ChapterTimeStart>
<ChapterTimeEnd>432000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Baby wants to rock</ChapString>
</ChapterDisplay>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>4</ChapterUID>
<ChapterTimeStart>432000000</ChapterTimeStart>
<ChapterTimeEnd>633000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Baby wants to bleep (pt.2)</ChapString>
</ChapterDisplay>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>5</ChapterUID>
<ChapterTimeStart>633000000</ChapterTimeStart>
<ChapterTimeEnd>748000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Baby wants to bleep (pt.3)</ChapString>
</ChapterDisplay>
</ChapterAtom>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>6</ChapterUID>
<ChapterTimeStart>750000000</ChapterTimeStart>
<ChapterTimeEnd>1178500000</ChapterTimeEnd>
<ChapterDisplay>
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<ChapString>Bleeper_O+2</ChapString>
</ChapterDisplay>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>7</ChapterUID>
<ChapterTimeStart>1180500000</ChapterTimeStart>
<ChapterTimeEnd>1340000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Baby wants to bleep (pt.4)</ChapString>
</ChapterDisplay>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>8</ChapterUID>
<ChapterTimeStart>1342000000</ChapterTimeStart>
<ChapterTimeEnd>1518000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Bleep to bleep</ChapString>
</ChapterDisplay>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>9</ChapterUID>
<ChapterTimeStart>1520000000</ChapterTimeStart>
<ChapterTimeEnd>2015000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Baby wants to bleep (k)</ChapString>
</ChapterDisplay>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>10</ChapterUID>
<ChapterTimeStart>2017000000</ChapterTimeStart>
<ChapterTimeEnd>2668000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Bleeper</ChapString>
</ChapterDisplay>
</ChapterAtom>
</EditionEntry>
</Chapters>
Figure 13: Nested Chapters Example. --- title: Attachments ---
23. Attachments
Matroska supports storage of related files and data in the
Attachments Element (a Top-Level Element). Attachment Elements can
be used to store related cover art, font files, transcripts, reports,
error recovery files, picture, or text-based annotations, copies of
specifications, or other ancillary files related to the Segment.
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Matroska Readers MUST NOT execute files stored as Attachment
Elements.
23.1. Cover Art
This section defines a set of guidelines for the storage of cover art
in Matroska files. A Matroska Reader MAY use embedded cover art to
display a representational still-image depiction of the multimedia
contents of the Matroska file.
Only JPEG and PNG image formats SHOULD be used for cover art
pictures.
There can be two different covers for a movie/album: a portrait style
(e.g., a DVD case) and a landscape style (e.g., a wide banner ad).
There can be two versions of the same cover, the normal cover and the
small cover. The dimension of the normal cover SHOULD be 600 pixels
on the smallest side -- for example, 960x600 for landscape, 600x800
for portrait, or 600x600 for square. The dimension of the small
cover SHOULD be 120 pixels on the smallest side -- for example,
192x120 or 120x160.
Versions of cover art can be differentiated by the filename, which is
stored in the FileName Element. The default filename of the normal
cover in square or portrait mode is cover.(jpg|png). When stored,
the normal cover SHOULD be the first Attachment in storage order.
The small cover SHOULD be prefixed with "small_", such as
small_cover.(jpg|png). The landscape variant SHOULD be suffixed with
"_land", such as cover_land.(jpg|png). The filenames are case
sensitive.
The following table provides examples of file names for cover art in
Attachments.
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+======================+===================+=================+
| FileName | Image Orientation | Pixel Length of |
| | | Smallest Side |
+======================+===================+=================+
| cover.jpg | Portrait or | 600 |
| | square | |
+----------------------+-------------------+-----------------+
| small_cover.png | Portrait or | 120 |
| | square | |
+----------------------+-------------------+-----------------+
| cover_land.png | Landscape | 600 |
+----------------------+-------------------+-----------------+
| small_cover_land.jpg | Landscape | 120 |
+----------------------+-------------------+-----------------+
Table 55: Cover Art Filenames
23.2. Font files
Font files MAY be added to a Matroska file as Attachments so that the
font file may be used to display an associated subtitle track. This
allows the presentation of a Matroska file to be consistent in
various environments where the needed fonts might not be available on
the local system.
Depending on the font format in question, each font file can contain
multiple font variants. Each font variant has a name which will be
referred to as Font Name from now on. This Font Name can be
different than the Attachment's FileName, even when disregarding the
extension. In order to select a font for display, a Matroska player
SHOULD consider both the Font Name and the base name of the
Attachment's FileName, preferring the former when there are multiple
matches.
Subtitle codecs, such as SubStation Alpha (SSA/ASS), usually refer to
a font by its Font Name, not by its filename. If none of the
Attachments are a match for the Font Name, the Matroska player SHOULD
attempt to find a system font whose Font Name matches the one used in
the subtitle track.
Since loading fonts temporarily can take a while, a Matroska player
usually loads or installs all the fonts found in attachments so they
are ready to be used during playback. Failure to use the font
attachment might result in incorrect rendering of the subtitles.
If a selected subtitle track has some AttachmentLink elements, the
player MAY use only these fonts.
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A Matroska player SHOULD handle the official font MIME types from
[RFC8081] when the system can handle the type: * font/sfnt: Generic
SFNT Font Type, * font/ttf: TTF Font Type, * font/otf: OpenType
Layout (OTF) Font Type, * font/collection: Collection Font Type, *
font/woff: WOFF 1.0, * font/woff2: WOFF 2.0.
Fonts in Matroska existed long before [RFC8081]. A few unofficial
MIME types for fonts were used in existing files. Therefore it is
RECOMMENDED for a Matroska player to support the following legacy
MIME types for font attachments:
* application/x-truetype-font: Truetype fonts, equivalent to font/
ttf and sometimes font/otf,
* application/x-font-ttf: TTF fonts, equivalent to font/ttf,
* application/vnd.ms-opentype: OpenType Layout fonts, equivalent to
font/otf
* application/font-sfnt: Generic SFNT Font Type, equivalent to font/
sfnt
* application/font-woff: WOFF 1.0, equivalent to font/woff
There may also be some font attachments with the application/octet-
stream MIME type. In that case the Matroska player MAY try to guess
the font type by checking the file extension of the
AttachedFile\FileName string. Common file extensions for fonts are:
* .ttf for Truetype fonts, equivalent to font/ttf, * .otf for
OpenType Layout fonts, equivalent to font/otf, * .ttc for Collection
fonts, equivalent to font/collection The file extension check MUST be
case insensitive.
Matroska writers SHOULD use a valid font MIME type from [RFC8081] in
the AttachedFile\FileMimeType of the font attachment.
23.3. They MAY use the MIME types found in older files when
compatibility with older players is necessary.
23.4. title: Cues
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24. Cues
The Cues Element provides an index of certain Cluster Elements to
allow for optimized seeking to absolute timestamps within the
Segment. The Cues Element contains one or many CuePoint Elements
which each MUST reference an absolute timestamp (via the CueTime
Element), a Track (via the CueTrack Element), and a Segment Position
(via the CueClusterPosition Element). Additional non-mandated
Elements are part of the CuePoint Element such as CueDuration,
CueRelativePosition, CueCodecState and others which provide any
Matroska Reader with additional information to use in the
optimization of seeking performance.
24.1. Recommendations
The following recommendations are provided to optimize Matroska
performance.
* Unless Matroska is used as a live stream, it SHOULD contain a Cues
Element.
* For each video track, each keyframe SHOULD be referenced by a
CuePoint Element.
* It is RECOMMENDED to not reference non-keyframes of video tracks
in Cues unless it references a Cluster Element which contains a
CodecState Element but no keyframes.
* For each subtitle track present, each subtitle frame SHOULD be
referenced by a CuePoint Element with a CueDuration Element.
* References to audio tracks MAY be skipped in CuePoint Elements if
a video track is present. When included the CuePoint Elements
SHOULD reference audio keyframes at most once every 500
milliseconds.
* If the referenced frame is not stored within the first
SimpleBlock, or first BlockGroup within its Cluster Element, then
the CueRelativePosition Element SHOULD be written to reference
where in the Cluster the reference frame is stored.
* If a CuePoint Element references Cluster Element that includes a
CodecState Element, then that CuePoint Element MUST use a
CueCodecState Element.
* CuePoint Elements SHOULD be numerically sorted in storage order by
the value of the CueTime Element. --- title: Matroska Streaming
---
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25. Matroska Streaming
In Matroska, there are two kinds of streaming: file access and
livestreaming.
25.1. File Access
File access can simply be reading a file located on your computer,
but also includes accessing a file from an HTTP (web) server or CIFS
(Windows share) server. These protocols are usually safe from
reading errors and seeking in the stream is possible. However, when
a file is stored far away or on a slow server, seeking can be an
expensive operation and SHOULD be avoided. The following guidelines,
when followed, help reduce the number of seeking operations for
regular playback and also have the playback start quickly without a
lot of data needed to read first (like a Cues Element, Attachment
Element or SeekHead Element).
Matroska, having a small overhead, is well suited for storing music/
videos on file servers without a big impact on the bandwidth used.
Matroska does not require the index to be loaded before playing,
which allows playback to start very quickly. The index can be loaded
only when seeking is requested the first time.
25.2. Livestreaming
Livestreaming is the equivalent of television broadcasting on the
internet. There are 2 families of servers for livestreaming: RTP/
RTSP and HTTP. Matroska is not meant to be used over RTP. RTP
already has timing and channel mechanisms that would be wasted if
doubled in Matroska. Additionally, having the same information at
the RTP and Matroska level would be a source of confusion if they do
not match. Livestreaming of Matroska over HTTP (or any other plain
protocol based on TCP) is possible.
A live Matroska stream is different from a file because it usually
has no known end (only ending when the client disconnects). For
this, all bits of the "size" portion of the Segment Element MUST be
set to 1. Another option is to concatenate Segment Elements with
known sizes, one after the other. This solution allows a change of
codec/resolution between each segment. For example, this allows for
a switch between 4:3 and 16:9 in a television program.
When Segment Elements are continuous, certain Elements, like
MetaSeek, Cues, Chapters, and Attachments, MUST NOT be used.
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It is possible for a Matroska Player to detect that a stream is not
seekable. If the stream has neither a MetaSeek list or a Cues list
at the beginning of the stream, it SHOULD be considered non-seekable.
Even though it is possible to seek blindly forward in the stream, it
is NOT RECOMMENDED.
In the context of live radio or web TV, it is possible to "tag" the
content while it is playing. The Tags Element can be placed between
Clusters each time it is necessary. In that case, the new Tags
Element MUST reset the previously encountered Tags Elements and use
the new values instead.
26. IANA Considerations
26.1. Matroska Element IDs Registry
This document creates a new IANA registry called the "Matroska
Element IDs" registry.
To register a new Element ID in this registry, one needs an Element
ID, a Change Controller (IESG or email of registrant) and an optional
Reference to a document describing the Element ID.
Element IDs are described in Section 5 of [RFC8794]. Element IDs are
encoded using the VINT mechanism described in Section 4 of [RFC8794]
and can be between one and five octets long. Five-octet-long Element
IDs are possible only if declared in the EBML header.
One-octet Element IDs MUST be between 0x80 and 0xFE. These items are
valuable because they are short, and they need to be used for
commonly repeated elements. Element IDs are to be allocated within
this range according to the "RFC Required" policy [RFC8126].
The following one-octet Element ID is RESERVED: 0xFF.
Values in the one-octet range of 0x00 to 0x7F are not valid for use
as an Element ID.
Two-octet Element IDs MUST be between 0x407F and 0x7FFE. Element IDs
are to be allocated within this range according to the "Specification
Required" policy [RFC8126].
The following two-octet Element ID is RESERVED: 0x7FFF.
Values in the two-octet ranges of 0x0000 to 0x4000 and 0x8000 to
0xFFFF are not valid for use as an Element ID.
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Three-octet Element IDs MUST be between 0x203FFF and 0x3FFFFE.
Element IDs are to be allocated within this range according to the
"First Come First Served" policy [RFC8126].
The following three-octet Element ID is RESERVED: 0x3FFFFF.
Values in the three-octet ranges of 0x000000 to 0x200000 and 0x400000
to 0xFFFFFF are not valid for use as an Element ID.
Four-octet Element IDs MUST be between 0x101FFFFF and 0x1FFFFFFE.
Four-octet Element IDs are somewhat special in that they are useful
for resynchronizing to major structures in the event of data
corruption or loss. As such, four-octet Element IDs are split into
two categories. Four-octet Element IDs whose lower three octets (as
encoded) would make printable 7-bit ASCII values (0x20 to 0x7E,
inclusive) MUST be allocated by the "Specification Required" policy.
Sequential allocation of values is not required: specifications
SHOULD include a specific request and are encouraged to do early
allocations.
To be clear about the above category: four-octet Element IDs always
start with hex 0x10 to 0x1F, and that octet may be chosen so that the
entire VINT has some desirable property, such as a specific CRC. The
other three octets, when ALL having values between 0x20 (32, ASCII
Space) and 0x7E (126, ASCII "~"), fall into this category.
Other four-octet Element IDs may be allocated by the "First Come
First Served" policy.
The following four-octet Element ID is RESERVED: 0x1FFFFFFF.
Values in the four-octet ranges of 0x00000000 to 0x10000000 and
0x20000000 to 0xFFFFFFFF are not valid for use as an Element ID.
Five-octet Element IDs (values from 0x080FFFFFFF to 0x0FFFFFFFFE) are
RESERVED according to the "Experimental Use" policy [RFC8126]: they
may be used by anyone at any time, but there is no coordination.
EBML IDs defined for the EBML Header -- as defined in Section 17.1 of
[RFC8794] -- MUST NOT be used as Matroska Element IDs.
Matroska Element IDs Values found in this document are assigned as
initial values as follows:
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+============+=============================+======================+
| Element ID | Element Name | Reference |
+============+=============================+======================+
| 0x1043A770 | Chapters | Described in |
| | | Section 8.1.7 |
+------------+-----------------------------+----------------------+
| 0x114D9B74 | SeekHead | Described in |
| | | Section 8.1.1 |
+------------+-----------------------------+----------------------+
| 0x1254C367 | Tags | Described in |
| | | Section 8.1.8 |
+------------+-----------------------------+----------------------+
| 0x1549A966 | Info | Described in |
| | | Section 8.1.2 |
+------------+-----------------------------+----------------------+
| 0x1654AE6B | Tracks | Described in |
| | | Section 8.1.4 |
+------------+-----------------------------+----------------------+
| 0x18538067 | Segment | Described in |
| | | Section 8.1 |
+------------+-----------------------------+----------------------+
| 0x1941A469 | Attachments | Described in |
| | | Section 8.1.6 |
+------------+-----------------------------+----------------------+
| 0x1C53BB6B | Cues | Described in |
| | | Section 8.1.5 |
+------------+-----------------------------+----------------------+
| 0x1F43B675 | Cluster | Described in |
| | | Section 8.1.3 |
+------------+-----------------------------+----------------------+
| 0x22B59C | Language | Described in |
| | | Section 8.1.4.1.21 |
+------------+-----------------------------+----------------------+
| 0x22B59D | LanguageIETF | Described in |
| | | Section 8.1.4.1.22 |
+------------+-----------------------------+----------------------+
| 0x23314F | TrackTimestampScale | Described in |
| | | Section 8.1.4.1.17 |
+------------+-----------------------------+----------------------+
| 0x234E7A | DefaultDecodedFieldDuration | Described in |
| | | Section 8.1.4.1.16 |
+------------+-----------------------------+----------------------+
| 0x2383E3 | FrameRate | Described in |
| | | Section 27.24 |
+------------+-----------------------------+----------------------+
| 0x23E383 | DefaultDuration | Described in |
| | | Section 8.1.4.1.15 |
+------------+-----------------------------+----------------------+
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| 0x258688 | CodecName | Described in |
| | | Section 8.1.4.1.25 |
+------------+-----------------------------+----------------------+
| 0x26B240 | CodecDownloadURL | Described in |
| | | Section 27.19 |
+------------+-----------------------------+----------------------+
| 0x2AD7B1 | TimestampScale | Described in |
| | | Section 8.1.2.9 |
+------------+-----------------------------+----------------------+
| 0x2EB524 | UncompressedFourCC | Described in Section |
| | | 8.1.4.1.31.14 |
+------------+-----------------------------+----------------------+
| 0x2FB523 | GammaValue | Described in |
| | | Section 27.23 |
+------------+-----------------------------+----------------------+
| 0x3A9697 | CodecSettings | Described in |
| | | Section 27.17 |
+------------+-----------------------------+----------------------+
| 0x3B4040 | CodecInfoURL | Described in |
| | | Section 27.18 |
+------------+-----------------------------+----------------------+
| 0x3C83AB | PrevFilename | Described in |
| | | Section 8.1.2.4 |
+------------+-----------------------------+----------------------+
| 0x3CB923 | PrevUID | Described in |
| | | Section 8.1.2.3 |
+------------+-----------------------------+----------------------+
| 0x3E83BB | NextFilename | Described in |
| | | Section 8.1.2.6 |
+------------+-----------------------------+----------------------+
| 0x3EB923 | NextUID | Described in |
| | | Section 8.1.2.5 |
+------------+-----------------------------+----------------------+
| 0x41A4 | BlockAddIDName | Described in |
| | | Section 8.1.4.1.19.2 |
+------------+-----------------------------+----------------------+
| 0x41E4 | BlockAdditionMapping | Described in |
| | | Section 8.1.4.1.19 |
+------------+-----------------------------+----------------------+
| 0x41E7 | BlockAddIDType | Described in |
| | | Section 8.1.4.1.19.3 |
+------------+-----------------------------+----------------------+
| 0x41ED | BlockAddIDExtraData | Described in |
| | | Section 8.1.4.1.19.4 |
+------------+-----------------------------+----------------------+
| 0x41F0 | BlockAddIDValue | Described in |
| | | Section 8.1.4.1.19.1 |
+------------+-----------------------------+----------------------+
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| 0x4254 | ContentCompAlgo | Described in |
| | | Section 8.1.4.1.34.6 |
+------------+-----------------------------+----------------------+
| 0x4255 | ContentCompSettings | Described in |
| | | Section 8.1.4.1.34.7 |
+------------+-----------------------------+----------------------+
| 0x437C | ChapLanguage | Described in |
| | | Section 8.1.7.1.4.11 |
+------------+-----------------------------+----------------------+
| 0x437D | ChapLanguageIETF | Described in |
| | | Section 8.1.7.1.4.12 |
+------------+-----------------------------+----------------------+
| 0x437E | ChapCountry | Described in |
| | | Section 8.1.7.1.4.13 |
+------------+-----------------------------+----------------------+
| 0x4444 | SegmentFamily | Described in |
| | | Section 8.1.2.7 |
+------------+-----------------------------+----------------------+
| 0x4461 | DateUTC | Described in |
| | | Section 8.1.2.11 |
+------------+-----------------------------+----------------------+
| 0x447A | TagLanguage | Described in |
| | | Section 8.1.8.1.2.2 |
+------------+-----------------------------+----------------------+
| 0x447B | TagLanguageIETF | Described in |
| | | Section 8.1.8.1.2.3 |
+------------+-----------------------------+----------------------+
| 0x4484 | TagDefault | Described in |
| | | Section 8.1.8.1.2.4 |
+------------+-----------------------------+----------------------+
| 0x4485 | TagBinary | Described in |
| | | Section 8.1.8.1.2.6 |
+------------+-----------------------------+----------------------+
| 0x4487 | TagString | Described in |
| | | Section 8.1.8.1.2.5 |
+------------+-----------------------------+----------------------+
| 0x4489 | Duration | Described in |
| | | Section 8.1.2.10 |
+------------+-----------------------------+----------------------+
| 0x44B4 | TagDefaultBogus | Described in |
| | | Section 27.41 |
+------------+-----------------------------+----------------------+
| 0x450D | ChapProcessPrivate | Described in |
| | | Section 8.1.7.1.4.16 |
+------------+-----------------------------+----------------------+
| 0x45A3 | TagName | Described in |
| | | Section 8.1.8.1.2.1 |
+------------+-----------------------------+----------------------+
Lhomme, et al. Expires 30 September 2022 [Page 172]
Internet-Draft Matroska Format March 2022
| 0x45B9 | EditionEntry | Described in |
| | | Section 8.1.7.1 |
+------------+-----------------------------+----------------------+
| 0x45BC | EditionUID | Described in |
| | | Section 8.1.7.1.1 |
+------------+-----------------------------+----------------------+
| 0x45DB | EditionFlagDefault | Described in |
| | | Section 8.1.7.1.2 |
+------------+-----------------------------+----------------------+
| 0x45DD | EditionFlagOrdered | Described in |
| | | Section 8.1.7.1.3 |
+------------+-----------------------------+----------------------+
| 0x465C | FileData | Described in |
| | | Section 8.1.6.1.4 |
+------------+-----------------------------+----------------------+
| 0x4660 | FileMimeType | Described in |
| | | Section 8.1.6.1.3 |
+------------+-----------------------------+----------------------+
| 0x4661 | FileUsedStartTime | Described in |
| | | Section 27.39 |
+------------+-----------------------------+----------------------+
| 0x4662 | FileUsedEndTime | Described in |
| | | Section 27.40 |
+------------+-----------------------------+----------------------+
| 0x466E | FileName | Described in |
| | | Section 8.1.6.1.2 |
+------------+-----------------------------+----------------------+
| 0x4675 | FileReferral | Described in |
| | | Section 27.38 |
+------------+-----------------------------+----------------------+
| 0x467E | FileDescription | Described in |
| | | Section 8.1.6.1.1 |
+------------+-----------------------------+----------------------+
| 0x46AE | FileUID | Described in |
| | | Section 8.1.6.1.5 |
+------------+-----------------------------+----------------------+
| 0x47E1 | ContentEncAlgo | Described in |
| | | Section 8.1.4.1.34.9 |
+------------+-----------------------------+----------------------+
| 0x47E2 | ContentEncKeyID | Described in Section |
| | | 8.1.4.1.34.10 |
+------------+-----------------------------+----------------------+
| 0x47E3 | ContentSignature | Described in |
| | | Section 27.31 |
+------------+-----------------------------+----------------------+
| 0x47E4 | ContentSigKeyID | Described in |
| | | Section 27.32 |
+------------+-----------------------------+----------------------+
Lhomme, et al. Expires 30 September 2022 [Page 173]
Internet-Draft Matroska Format March 2022
| 0x47E5 | ContentSigAlgo | Described in |
| | | Section 27.33 |
+------------+-----------------------------+----------------------+
| 0x47E6 | ContentSigHashAlgo | Described in |
| | | Section 27.34 |
+------------+-----------------------------+----------------------+
| 0x47E7 | ContentEncAESSettings | Described in Section |
| | | 8.1.4.1.34.11 |
+------------+-----------------------------+----------------------+
| 0x47E8 | AESSettingsCipherMode | Described in Section |
| | | 8.1.4.1.34.12 |
+------------+-----------------------------+----------------------+
| 0x4D80 | MuxingApp | Described in |
| | | Section 8.1.2.13 |
+------------+-----------------------------+----------------------+
| 0x4DBB | Seek | Described in |
| | | Section 8.1.1.1 |
+------------+-----------------------------+----------------------+
| 0x5031 | ContentEncodingOrder | Described in |
| | | Section 8.1.4.1.34.2 |
+------------+-----------------------------+----------------------+
| 0x5032 | ContentEncodingScope | Described in |
| | | Section 8.1.4.1.34.3 |
+------------+-----------------------------+----------------------+
| 0x5033 | ContentEncodingType | Described in |
| | | Section 8.1.4.1.34.4 |
+------------+-----------------------------+----------------------+
| 0x5034 | ContentCompression | Described in |
| | | Section 8.1.4.1.34.5 |
+------------+-----------------------------+----------------------+
| 0x5035 | ContentEncryption | Described in |
| | | Section 8.1.4.1.34.8 |
+------------+-----------------------------+----------------------+
| 0x535F | CueRefNumber | Described in |
| | | Section 27.36 |
+------------+-----------------------------+----------------------+
| 0x536E | Name | Described in |
| | | Section 8.1.4.1.20 |
+------------+-----------------------------+----------------------+
| 0x5378 | CueBlockNumber | Described in |
| | | Section 8.1.5.1.2.5 |
+------------+-----------------------------+----------------------+
| 0x537F | TrackOffset | Described in |
| | | Section 27.16 |
+------------+-----------------------------+----------------------+
| 0x53AB | SeekID | Described in |
| | | Section 8.1.1.1.1 |
+------------+-----------------------------+----------------------+
Lhomme, et al. Expires 30 September 2022 [Page 174]
Internet-Draft Matroska Format March 2022
| 0x53AC | SeekPosition | Described in |
| | | Section 8.1.1.1.2 |
+------------+-----------------------------+----------------------+
| 0x53B8 | StereoMode | Described in |
| | | Section 8.1.4.1.31.3 |
+------------+-----------------------------+----------------------+
| 0x53B9 | OldStereoMode | Described in |
| | | Section 27.21 |
+------------+-----------------------------+----------------------+
| 0x53C0 | AlphaMode | Described in |
| | | Section 8.1.4.1.31.4 |
+------------+-----------------------------+----------------------+
| 0x54AA | PixelCropBottom | Described in |
| | | Section 8.1.4.1.31.7 |
+------------+-----------------------------+----------------------+
| 0x54B0 | DisplayWidth | Described in Section |
| | | 8.1.4.1.31.11 |
+------------+-----------------------------+----------------------+
| 0x54B2 | DisplayUnit | Described in Section |
| | | 8.1.4.1.31.13 |
+------------+-----------------------------+----------------------+
| 0x54B3 | AspectRatioType | Described in |
| | | Section 27.22 |
+------------+-----------------------------+----------------------+
| 0x54BA | DisplayHeight | Described in Section |
| | | 8.1.4.1.31.12 |
+------------+-----------------------------+----------------------+
| 0x54BB | PixelCropTop | Described in |
| | | Section 8.1.4.1.31.8 |
+------------+-----------------------------+----------------------+
| 0x54CC | PixelCropLeft | Described in |
| | | Section 8.1.4.1.31.9 |
+------------+-----------------------------+----------------------+
| 0x54DD | PixelCropRight | Described in Section |
| | | 8.1.4.1.31.10 |
+------------+-----------------------------+----------------------+
| 0x55AA | FlagForced | Described in |
| | | Section 8.1.4.1.6 |
+------------+-----------------------------+----------------------+
| 0x55AB | FlagHearingImpaired | Described in |
| | | Section 8.1.4.1.7 |
+------------+-----------------------------+----------------------+
| 0x55AC | FlagVisualImpaired | Described in |
| | | Section 8.1.4.1.8 |
+------------+-----------------------------+----------------------+
| 0x55AD | FlagTextDescriptions | Described in |
| | | Section 8.1.4.1.9 |
+------------+-----------------------------+----------------------+
Lhomme, et al. Expires 30 September 2022 [Page 175]
Internet-Draft Matroska Format March 2022
| 0x55AE | FlagOriginal | Described in |
| | | Section 8.1.4.1.10 |
+------------+-----------------------------+----------------------+
| 0x55AF | FlagCommentary | Described in |
| | | Section 8.1.4.1.11 |
+------------+-----------------------------+----------------------+
| 0x55B0 | Colour | Described in Section |
| | | 8.1.4.1.31.15 |
+------------+-----------------------------+----------------------+
| 0x55B1 | MatrixCoefficients | Described in Section |
| | | 8.1.4.1.31.16 |
+------------+-----------------------------+----------------------+
| 0x55B2 | BitsPerChannel | Described in Section |
| | | 8.1.4.1.31.17 |
+------------+-----------------------------+----------------------+
| 0x55B3 | ChromaSubsamplingHorz | Described in Section |
| | | 8.1.4.1.31.18 |
+------------+-----------------------------+----------------------+
| 0x55B4 | ChromaSubsamplingVert | Described in Section |
| | | 8.1.4.1.31.19 |
+------------+-----------------------------+----------------------+
| 0x55B5 | CbSubsamplingHorz | Described in Section |
| | | 8.1.4.1.31.20 |
+------------+-----------------------------+----------------------+
| 0x55B6 | CbSubsamplingVert | Described in Section |
| | | 8.1.4.1.31.21 |
+------------+-----------------------------+----------------------+
| 0x55B7 | ChromaSitingHorz | Described in Section |
| | | 8.1.4.1.31.22 |
+------------+-----------------------------+----------------------+
| 0x55B8 | ChromaSitingVert | Described in Section |
| | | 8.1.4.1.31.23 |
+------------+-----------------------------+----------------------+
| 0x55B9 | Range | Described in Section |
| | | 8.1.4.1.31.24 |
+------------+-----------------------------+----------------------+
| 0x55BA | TransferCharacteristics | Described in Section |
| | | 8.1.4.1.31.25 |
+------------+-----------------------------+----------------------+
| 0x55BB | Primaries | Described in Section |
| | | 8.1.4.1.31.26 |
+------------+-----------------------------+----------------------+
| 0x55BC | MaxCLL | Described in Section |
| | | 8.1.4.1.31.27 |
+------------+-----------------------------+----------------------+
| 0x55BD | MaxFALL | Described in Section |
| | | 8.1.4.1.31.28 |
+------------+-----------------------------+----------------------+
Lhomme, et al. Expires 30 September 2022 [Page 176]
Internet-Draft Matroska Format March 2022
| 0x55D0 | MasteringMetadata | Described in Section |
| | | 8.1.4.1.31.29 |
+------------+-----------------------------+----------------------+
| 0x55D1 | PrimaryRChromaticityX | Described in Section |
| | | 8.1.4.1.31.30 |
+------------+-----------------------------+----------------------+
| 0x55D2 | PrimaryRChromaticityY | Described in Section |
| | | 8.1.4.1.31.31 |
+------------+-----------------------------+----------------------+
| 0x55D3 | PrimaryGChromaticityX | Described in Section |
| | | 8.1.4.1.31.32 |
+------------+-----------------------------+----------------------+
| 0x55D4 | PrimaryGChromaticityY | Described in Section |
| | | 8.1.4.1.31.33 |
+------------+-----------------------------+----------------------+
| 0x55D5 | PrimaryBChromaticityX | Described in Section |
| | | 8.1.4.1.31.34 |
+------------+-----------------------------+----------------------+
| 0x55D6 | PrimaryBChromaticityY | Described in Section |
| | | 8.1.4.1.31.35 |
+------------+-----------------------------+----------------------+
| 0x55D7 | WhitePointChromaticityX | Described in Section |
| | | 8.1.4.1.31.36 |
+------------+-----------------------------+----------------------+
| 0x55D8 | WhitePointChromaticityY | Described in Section |
| | | 8.1.4.1.31.37 |
+------------+-----------------------------+----------------------+
| 0x55D9 | LuminanceMax | Described in Section |
| | | 8.1.4.1.31.38 |
+------------+-----------------------------+----------------------+
| 0x55DA | LuminanceMin | Described in Section |
| | | 8.1.4.1.31.39 |
+------------+-----------------------------+----------------------+
| 0x55EE | MaxBlockAdditionID | Described in |
| | | Section 8.1.4.1.18 |
+------------+-----------------------------+----------------------+
| 0x5654 | ChapterStringUID | Described in |
| | | Section 8.1.7.1.4.2 |
+------------+-----------------------------+----------------------+
| 0x56AA | CodecDelay | Described in |
| | | Section 8.1.4.1.28 |
+------------+-----------------------------+----------------------+
| 0x56BB | SeekPreRoll | Described in |
| | | Section 8.1.4.1.29 |
+------------+-----------------------------+----------------------+
| 0x5741 | WritingApp | Described in |
| | | Section 8.1.2.14 |
+------------+-----------------------------+----------------------+
Lhomme, et al. Expires 30 September 2022 [Page 177]
Internet-Draft Matroska Format March 2022
| 0x5854 | SilentTracks | Described in |
| | | Section 27.1 |
+------------+-----------------------------+----------------------+
| 0x58D7 | SilentTrackNumber | Described in |
| | | Section 27.2 |
+------------+-----------------------------+----------------------+
| 0x61A7 | AttachedFile | Described in |
| | | Section 8.1.6.1 |
+------------+-----------------------------+----------------------+
| 0x6240 | ContentEncoding | Described in |
| | | Section 8.1.4.1.34.1 |
+------------+-----------------------------+----------------------+
| 0x6264 | BitDepth | Described in |
| | | Section 8.1.4.1.32.4 |
+------------+-----------------------------+----------------------+
| 0x63A2 | CodecPrivate | Described in |
| | | Section 8.1.4.1.24 |
+------------+-----------------------------+----------------------+
| 0x63C0 | Targets | Described in |
| | | Section 8.1.8.1.1 |
+------------+-----------------------------+----------------------+
| 0x63C3 | ChapterPhysicalEquiv | Described in |
| | | Section 8.1.7.1.4.8 |
+------------+-----------------------------+----------------------+
| 0x63C4 | TagChapterUID | Described in |
| | | Section 8.1.8.1.1.5 |
+------------+-----------------------------+----------------------+
| 0x63C5 | TagTrackUID | Described in |
| | | Section 8.1.8.1.1.3 |
+------------+-----------------------------+----------------------+
| 0x63C6 | TagAttachmentUID | Described in |
| | | Section 8.1.8.1.1.6 |
+------------+-----------------------------+----------------------+
| 0x63C9 | TagEditionUID | Described in |
| | | Section 8.1.8.1.1.4 |
+------------+-----------------------------+----------------------+
| 0x63CA | TargetType | Described in |
| | | Section 8.1.8.1.1.2 |
+------------+-----------------------------+----------------------+
| 0x6624 | TrackTranslate | Described in |
| | | Section 8.1.4.1.30 |
+------------+-----------------------------+----------------------+
| 0x66A5 | TrackTranslateTrackID | Described in |
| | | Section 8.1.4.1.30.1 |
+------------+-----------------------------+----------------------+
| 0x66BF | TrackTranslateCodec | Described in |
| | | Section 8.1.4.1.30.2 |
+------------+-----------------------------+----------------------+
Lhomme, et al. Expires 30 September 2022 [Page 178]
Internet-Draft Matroska Format March 2022
| 0x66FC | TrackTranslateEditionUID | Described in |
| | | Section 8.1.4.1.30.3 |
+------------+-----------------------------+----------------------+
| 0x67C8 | SimpleTag | Described in |
| | | Section 8.1.8.1.2 |
+------------+-----------------------------+----------------------+
| 0x68CA | TargetTypeValue | Described in |
| | | Section 8.1.8.1.1.1 |
+------------+-----------------------------+----------------------+
| 0x6911 | ChapProcessCommand | Described in |
| | | Section 8.1.7.1.4.17 |
+------------+-----------------------------+----------------------+
| 0x6922 | ChapProcessTime | Described in |
| | | Section 8.1.7.1.4.18 |
+------------+-----------------------------+----------------------+
| 0x6924 | ChapterTranslate | Described in |
| | | Section 8.1.2.8 |
+------------+-----------------------------+----------------------+
| 0x6933 | ChapProcessData | Described in |
| | | Section 8.1.7.1.4.19 |
+------------+-----------------------------+----------------------+
| 0x6944 | ChapProcess | Described in |
| | | Section 8.1.7.1.4.14 |
+------------+-----------------------------+----------------------+
| 0x6955 | ChapProcessCodecID | Described in |
| | | Section 8.1.7.1.4.15 |
+------------+-----------------------------+----------------------+
| 0x69A5 | ChapterTranslateID | Described in |
| | | Section 8.1.2.8.1 |
+------------+-----------------------------+----------------------+
| 0x69BF | ChapterTranslateCodec | Described in |
| | | Section 8.1.2.8.2 |
+------------+-----------------------------+----------------------+
| 0x69FC | ChapterTranslateEditionUID | Described in |
| | | Section 8.1.2.8.3 |
+------------+-----------------------------+----------------------+
| 0x6D80 | ContentEncodings | Described in |
| | | Section 8.1.4.1.34 |
+------------+-----------------------------+----------------------+
| 0x6DE7 | MinCache | Described in |
| | | Section 8.1.4.1.13 |
+------------+-----------------------------+----------------------+
| 0x6DF8 | MaxCache | Described in |
| | | Section 8.1.4.1.14 |
+------------+-----------------------------+----------------------+
| 0x6E67 | ChapterSegmentUID | Described in |
| | | Section 8.1.7.1.4.6 |
+------------+-----------------------------+----------------------+
Lhomme, et al. Expires 30 September 2022 [Page 179]
Internet-Draft Matroska Format March 2022
| 0x6EBC | ChapterSegmentEditionUID | Described in |
| | | Section 8.1.7.1.4.7 |
+------------+-----------------------------+----------------------+
| 0x6FAB | TrackOverlay | Described in |
| | | Section 8.1.4.1.27 |
+------------+-----------------------------+----------------------+
| 0x7373 | Tag | Described in |
| | | Section 8.1.8.1 |
+------------+-----------------------------+----------------------+
| 0x7384 | SegmentFilename | Described in |
| | | Section 8.1.2.2 |
+------------+-----------------------------+----------------------+
| 0x73A4 | SegmentUID | Described in |
| | | Section 8.1.2.1 |
+------------+-----------------------------+----------------------+
| 0x73C4 | ChapterUID | Described in |
| | | Section 8.1.7.1.4.1 |
+------------+-----------------------------+----------------------+
| 0x73C5 | TrackUID | Described in |
| | | Section 8.1.4.1.2 |
+------------+-----------------------------+----------------------+
| 0x7446 | AttachmentLink | Described in |
| | | Section 8.1.4.1.26 |
+------------+-----------------------------+----------------------+
| 0x75A1 | BlockAdditions | Described in |
| | | Section 8.1.3.5.2 |
+------------+-----------------------------+----------------------+
| 0x75A2 | DiscardPadding | Described in |
| | | Section 8.1.3.5.7 |
+------------+-----------------------------+----------------------+
| 0x7670 | Projection | Described in Section |
| | | 8.1.4.1.31.40 |
+------------+-----------------------------+----------------------+
| 0x7671 | ProjectionType | Described in Section |
| | | 8.1.4.1.31.41 |
+------------+-----------------------------+----------------------+
| 0x7672 | ProjectionPrivate | Described in Section |
| | | 8.1.4.1.31.42 |
+------------+-----------------------------+----------------------+
| 0x7673 | ProjectionPoseYaw | Described in Section |
| | | 8.1.4.1.31.43 |
+------------+-----------------------------+----------------------+
| 0x7674 | ProjectionPosePitch | Described in Section |
| | | 8.1.4.1.31.44 |
+------------+-----------------------------+----------------------+
| 0x7675 | ProjectionPoseRoll | Described in Section |
| | | 8.1.4.1.31.45 |
+------------+-----------------------------+----------------------+
Lhomme, et al. Expires 30 September 2022 [Page 180]
Internet-Draft Matroska Format March 2022
| 0x78B5 | OutputSamplingFrequency | Described in |
| | | Section 8.1.4.1.32.2 |
+------------+-----------------------------+----------------------+
| 0x7BA9 | Title | Described in |
| | | Section 8.1.2.12 |
+------------+-----------------------------+----------------------+
| 0x7D7B | ChannelPositions | Described in |
| | | Section 27.25 |
+------------+-----------------------------+----------------------+
| 0x80 | ChapterDisplay | Described in |
| | | Section 8.1.7.1.4.9 |
+------------+-----------------------------+----------------------+
| 0x83 | TrackType | Described in |
| | | Section 8.1.4.1.3 |
+------------+-----------------------------+----------------------+
| 0x85 | ChapString | Described in |
| | | Section 8.1.7.1.4.10 |
+------------+-----------------------------+----------------------+
| 0x86 | CodecID | Described in |
| | | Section 8.1.4.1.23 |
+------------+-----------------------------+----------------------+
| 0x88 | FlagDefault | Described in |
| | | Section 8.1.4.1.5 |
+------------+-----------------------------+----------------------+
| 0x8E | Slices | Described in |
| | | Section 27.5 |
+------------+-----------------------------+----------------------+
| 0x91 | ChapterTimeStart | Described in |
| | | Section 8.1.7.1.4.3 |
+------------+-----------------------------+----------------------+
| 0x92 | ChapterTimeEnd | Described in |
| | | Section 8.1.7.1.4.4 |
+------------+-----------------------------+----------------------+
| 0x96 | CueRefTime | Described in |
| | | Section 8.1.5.1.2.8 |
+------------+-----------------------------+----------------------+
| 0x97 | CueRefCluster | Described in |
| | | Section 27.35 |
+------------+-----------------------------+----------------------+
| 0x98 | ChapterFlagHidden | Described in |
| | | Section 8.1.7.1.4.5 |
+------------+-----------------------------+----------------------+
| 0x9A | FlagInterlaced | Described in |
| | | Section 8.1.4.1.31.1 |
+------------+-----------------------------+----------------------+
| 0x9B | BlockDuration | Described in |
| | | Section 8.1.3.5.3 |
+------------+-----------------------------+----------------------+
Lhomme, et al. Expires 30 September 2022 [Page 181]
Internet-Draft Matroska Format March 2022
| 0x9C | FlagLacing | Described in |
| | | Section 8.1.4.1.12 |
+------------+-----------------------------+----------------------+
| 0x9D | FieldOrder | Described in |
| | | Section 8.1.4.1.31.2 |
+------------+-----------------------------+----------------------+
| 0x9F | Channels | Described in |
| | | Section 8.1.4.1.32.3 |
+------------+-----------------------------+----------------------+
| 0xA0 | BlockGroup | Described in |
| | | Section 8.1.3.5 |
+------------+-----------------------------+----------------------+
| 0xA1 | Block | Described in |
| | | Section 8.1.3.5.1 |
+------------+-----------------------------+----------------------+
| 0xA2 | BlockVirtual | Described in |
| | | Section 27.3 |
+------------+-----------------------------+----------------------+
| 0xA3 | SimpleBlock | Described in |
| | | Section 8.1.3.4 |
+------------+-----------------------------+----------------------+
| 0xA4 | CodecState | Described in |
| | | Section 8.1.3.5.6 |
+------------+-----------------------------+----------------------+
| 0xA5 | BlockAdditional | Described in |
| | | Section 8.1.3.5.2.3 |
+------------+-----------------------------+----------------------+
| 0xA6 | BlockMore | Described in |
| | | Section 8.1.3.5.2.1 |
+------------+-----------------------------+----------------------+
| 0xA7 | Position | Described in |
| | | Section 8.1.3.2 |
+------------+-----------------------------+----------------------+
| 0xAA | CodecDecodeAll | Described in |
| | | Section 27.20 |
+------------+-----------------------------+----------------------+
| 0xAB | PrevSize | Described in |
| | | Section 8.1.3.3 |
+------------+-----------------------------+----------------------+
| 0xAE | TrackEntry | Described in |
| | | Section 8.1.4.1 |
+------------+-----------------------------+----------------------+
| 0xAF | EncryptedBlock | Described in |
| | | Section 27.15 |
+------------+-----------------------------+----------------------+
| 0xB0 | PixelWidth | Described in |
| | | Section 8.1.4.1.31.5 |
+------------+-----------------------------+----------------------+
Lhomme, et al. Expires 30 September 2022 [Page 182]
Internet-Draft Matroska Format March 2022
| 0xB2 | CueDuration | Described in |
| | | Section 8.1.5.1.2.4 |
+------------+-----------------------------+----------------------+
| 0xB3 | CueTime | Described in |
| | | Section 8.1.5.1.1 |
+------------+-----------------------------+----------------------+
| 0xB5 | SamplingFrequency | Described in |
| | | Section 8.1.4.1.32.1 |
+------------+-----------------------------+----------------------+
| 0xB6 | ChapterAtom | Described in |
| | | Section 8.1.7.1.4 |
+------------+-----------------------------+----------------------+
| 0xB7 | CueTrackPositions | Described in |
| | | Section 8.1.5.1.2 |
+------------+-----------------------------+----------------------+
| 0xB9 | FlagEnabled | Described in |
| | | Section 8.1.4.1.4 |
+------------+-----------------------------+----------------------+
| 0xBA | PixelHeight | Described in |
| | | Section 8.1.4.1.31.6 |
+------------+-----------------------------+----------------------+
| 0xBB | CuePoint | Described in |
| | | Section 8.1.5.1 |
+------------+-----------------------------+----------------------+
| 0xC0 | TrickTrackUID | Described in |
| | | Section 27.26 |
+------------+-----------------------------+----------------------+
| 0xC1 | TrickTrackSegmentUID | Described in |
| | | Section 27.27 |
+------------+-----------------------------+----------------------+
| 0xC4 | TrickMasterTrackSegmentUID | Described in |
| | | Section 27.30 |
+------------+-----------------------------+----------------------+
| 0xC6 | TrickTrackFlag | Described in |
| | | Section 27.28 |
+------------+-----------------------------+----------------------+
| 0xC7 | TrickMasterTrackUID | Described in |
| | | Section 27.29 |
+------------+-----------------------------+----------------------+
| 0xC8 | ReferenceFrame | Described in |
| | | Section 27.12 |
+------------+-----------------------------+----------------------+
| 0xC9 | ReferenceOffset | Described in |
| | | Section 27.13 |
+------------+-----------------------------+----------------------+
| 0xCA | ReferenceTimestamp | Described in |
| | | Section 27.14 |
+------------+-----------------------------+----------------------+
Lhomme, et al. Expires 30 September 2022 [Page 183]
Internet-Draft Matroska Format March 2022
| 0xCB | BlockAdditionID | Described in |
| | | Section 27.9 |
+------------+-----------------------------+----------------------+
| 0xCC | LaceNumber | Described in |
| | | Section 27.7 |
+------------+-----------------------------+----------------------+
| 0xCD | FrameNumber | Described in |
| | | Section 27.8 |
+------------+-----------------------------+----------------------+
| 0xCE | Delay | Described in |
| | | Section 27.10 |
+------------+-----------------------------+----------------------+
| 0xCF | SliceDuration | Described in |
| | | Section 27.11 |
+------------+-----------------------------+----------------------+
| 0xD7 | TrackNumber | Described in |
| | | Section 8.1.4.1.1 |
+------------+-----------------------------+----------------------+
| 0xDB | CueReference | Described in |
| | | Section 8.1.5.1.2.7 |
+------------+-----------------------------+----------------------+
| 0xE0 | Video | Described in |
| | | Section 8.1.4.1.31 |
+------------+-----------------------------+----------------------+
| 0xE1 | Audio | Described in |
| | | Section 8.1.4.1.32 |
+------------+-----------------------------+----------------------+
| 0xE2 | TrackOperation | Described in |
| | | Section 8.1.4.1.33 |
+------------+-----------------------------+----------------------+
| 0xE3 | TrackCombinePlanes | Described in |
| | | Section 8.1.4.1.33.1 |
+------------+-----------------------------+----------------------+
| 0xE4 | TrackPlane | Described in |
| | | Section 8.1.4.1.33.2 |
+------------+-----------------------------+----------------------+
| 0xE5 | TrackPlaneUID | Described in |
| | | Section 8.1.4.1.33.3 |
+------------+-----------------------------+----------------------+
| 0xE6 | TrackPlaneType | Described in |
| | | Section 8.1.4.1.33.4 |
+------------+-----------------------------+----------------------+
| 0xE7 | Timestamp | Described in |
| | | Section 8.1.3.1 |
+------------+-----------------------------+----------------------+
| 0xE8 | TimeSlice | Described in |
| | | Section 27.6 |
+------------+-----------------------------+----------------------+
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| 0xE9 | TrackJoinBlocks | Described in |
| | | Section 8.1.4.1.33.5 |
+------------+-----------------------------+----------------------+
| 0xEA | CueCodecState | Described in |
| | | Section 8.1.5.1.2.6 |
+------------+-----------------------------+----------------------+
| 0xEB | CueRefCodecState | Described in |
| | | Section 27.37 |
+------------+-----------------------------+----------------------+
| 0xED | TrackJoinUID | Described in |
| | | Section 8.1.4.1.33.6 |
+------------+-----------------------------+----------------------+
| 0xEE | BlockAddID | Described in |
| | | Section 8.1.3.5.2.2 |
+------------+-----------------------------+----------------------+
| 0xF0 | CueRelativePosition | Described in |
| | | Section 8.1.5.1.2.3 |
+------------+-----------------------------+----------------------+
| 0xF1 | CueClusterPosition | Described in |
| | | Section 8.1.5.1.2.2 |
+------------+-----------------------------+----------------------+
| 0xF7 | CueTrack | Described in |
| | | Section 8.1.5.1.2.1 |
+------------+-----------------------------+----------------------+
| 0xFA | ReferencePriority | Described in |
| | | Section 8.1.3.5.4 |
+------------+-----------------------------+----------------------+
| 0xFB | ReferenceBlock | Described in |
| | | Section 8.1.3.5.5 |
+------------+-----------------------------+----------------------+
| 0xFD | ReferenceVirtual | Described in |
| | | Section 27.4 |
+------------+-----------------------------+----------------------+
Table 56: IDs and Names for Matroska Element IDs assigned by
this document
26.2. Chapter Codec IDs Registry
This document creates a new IANA registry called the "Matroska
Chapter Codec IDs" registry. The values correspond to the
ChapProcessCodecID value described in Section 8.1.7.1.4.15.
ChapProcessCodecID values of "0" and "1" are RESERVED to the IETF for
future use.
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26.3. MIME Types
Matroska files and streams are found in three main forms: audio-video
files, audio-only and occasionally with stereoscopic video tracks.
The MIME types to use for each type is:
* "video/matroska" for streams containing video tracks
* "audio/matroska" for streams containing audio tracks with no video
tracks
* "video/matroska-3d" for streams containing at least a stereoscopic
video track
Historically Matroska files and streams have used the following MIME
types with a "x-" prefix:
* "video/x-matroska" for streams containing video tracks
* "audio/x-matroska" for streams containing audio tracks with no
video tracks
* "video/x-matroska-3d" for streams containing at least a
stereoscopic video track
For better compatibility a system SHOULD be able to handle both
formats. Newer systems SHOULD NOT use the historic format and use
the format that follows the [RFC6838] format instead.
27. Annex A: Historic Deprecated Elements
As Matroska evolved since 2002 many parts that were considered for
use in the format were never used and often incorrectly designed.
Many of the elements that were then defined are not found in any
known files but were part of public specs. DivX also had a few
custom elements that were designed for custom features.
We list these elements that have a known ID that SHOULD NOT be reused
to avoid colliding with existing files.
27.1. SilentTracks Element
path: \Segment\Cluster\SilentTracks
id: 0x5854
type: master
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documentation: The list of tracks that are not used in that part of
the stream. It is useful when using overlay tracks on seeking or
to decide what track to use.
27.2. SilentTrackNumber Element
path: \Segment\Cluster\SilentTracks\SilentTrackNumber
id: 0x58D7
type: uinteger
documentation: One of the track number that are not used from now on
in the stream. It could change later if not specified as silent
in a further Cluster.
27.3. BlockVirtual Element
path: \Segment\Cluster\BlockGroup\BlockVirtual
id: 0xA2
type: binary
documentation: A Block with no data. It MUST be stored in the
stream at the place the real Block would be in display order.
27.4. ReferenceVirtual Element
path: \Segment\Cluster\BlockGroup\ReferenceVirtual
id: 0xFD
type: integer
documentation: The Segment Position of the data that would otherwise
be in position of the virtual block.
27.5. Slices Element
path: \Segment\Cluster\BlockGroup\Slices
id: 0x8E
type: master
documentation: Contains slices description.
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27.6. TimeSlice Element
path: \Segment\Cluster\BlockGroup\Slices\TimeSlice
id: 0xE8
type: master
documentation: Contains extra time information about the data
contained in the Block. Being able to interpret this Element is
not REQUIRED for playback.
27.7. LaceNumber Element
path: \Segment\Cluster\BlockGroup\Slices\TimeSlice\LaceNumber
id: 0xCC
type: uinteger
documentation: The reverse number of the frame in the lace (0 is the
last frame, 1 is the next to last, etc). Being able to interpret
this Element is not REQUIRED for playback.
27.8. FrameNumber Element
path: \Segment\Cluster\BlockGroup\Slices\TimeSlice\FrameNumber
id: 0xCD
type: uinteger
documentation: The number of the frame to generate from this lace
with this delay (allow you to generate many frames from the same
Block/Frame).
27.9. BlockAdditionID Element
path: \Segment\Cluster\BlockGroup\Slices\TimeSlice\BlockAdditionID
id: 0xCB
type: uinteger
documentation: The ID of the BlockAdditional Element (0 is the main
Block).
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27.10. Delay Element
path: \Segment\Cluster\BlockGroup\Slices\TimeSlice\Delay
id: 0xCE
type: uinteger
documentation: The delay to apply to the Element, expressed in Track
Ticks; see Section 13.1.
27.11. SliceDuration Element
path: \Segment\Cluster\BlockGroup\Slices\TimeSlice\SliceDuration
id: 0xCF
type: uinteger
documentation: The duration to apply to the Element, expressed in
Track Ticks; see Section 13.1.
27.12. ReferenceFrame Element
path: \Segment\Cluster\BlockGroup\ReferenceFrame
id: 0xC8
type: master
documentation: Contains information about the last reference frame.
See [DivXTrickTrack].
27.13. ReferenceOffset Element
path: \Segment\Cluster\BlockGroup\ReferenceFrame\ReferenceOffset
id: 0xC9
type: uinteger
documentation: The relative offset, in bytes, from the previous
BlockGroup element for this Smooth FF/RW video track to the
containing BlockGroup element. See [DivXTrickTrack].
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27.14. ReferenceTimestamp Element
path: \Segment\Cluster\BlockGroup\ReferenceFrame\ReferenceTimestamp
id: 0xCA
type: uinteger
documentation: The timestamp of the BlockGroup pointed to by
ReferenceOffset, expressed in Track Ticks; see Section 13.1. See
[DivXTrickTrack].
27.15. EncryptedBlock Element
path: \Segment\Cluster\EncryptedBlock
id: 0xAF
type: binary
documentation: Similar to SimpleBlock, see Section 12.3, but the
data inside the Block are Transformed (encrypt and/or signed).
27.16. TrackOffset Element
path: \Segment\Tracks\TrackEntry\TrackOffset
id: 0x537F
type: integer
documentation: A value to add to the Block's Timestamp, expressed in
Matroska Ticks -- ie in nanoseconds; see Section 13.1. This can
be used to adjust the playback offset of a track.
27.17. CodecSettings Element
path: \Segment\Tracks\TrackEntry\CodecSettings
id: 0x3A9697
type: utf-8
documentation: A string describing the encoding setting used.
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27.18. CodecInfoURL Element
path: \Segment\Tracks\TrackEntry\CodecInfoURL
id: 0x3B4040
type: string
documentation: A URL to find information about the codec used.
27.19. CodecDownloadURL Element
path: \Segment\Tracks\TrackEntry\CodecDownloadURL
id: 0x26B240
type: string
documentation: A URL to download about the codec used.
27.20. CodecDecodeAll Element
path: \Segment\Tracks\TrackEntry\CodecDecodeAll
id: 0xAA
type: uinteger
documentation: Set to 1 if the codec can decode potentially damaged
data.
27.21. OldStereoMode Element
path: \Segment\Tracks\TrackEntry\Video\OldStereoMode
id: 0x53B9
type: uinteger
documentation: DEPRECATED, DO NOT USE. Bogus StereoMode value used
in old versions of libmatroska.
27.22. AspectRatioType Element
path: \Segment\Tracks\TrackEntry\Video\AspectRatioType
id: 0x54B3
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type: uinteger
documentation: Specify the possible modifications to the aspect
ratio.
27.23. GammaValue Element
path: \Segment\Tracks\TrackEntry\Video\GammaValue
id: 0x2FB523
type: float
documentation: Gamma Value.
27.24. FrameRate Element
path: \Segment\Tracks\TrackEntry\Video\FrameRate
id: 0x2383E3
type: float
documentation: Number of frames per second. This value is
Informational only. It is intended for constant frame rate
streams, and SHOULD NOT be used for a variable frame rate
TrackEntry.
27.25. ChannelPositions Element
path: \Segment\Tracks\TrackEntry\Audio\ChannelPositions
id: 0x7D7B
type: binary
documentation: Table of horizontal angles for each successive
channel.
27.26. TrickTrackUID Element
path: \Segment\Tracks\TrackEntry\TrickTrackUID
id: 0xC0
type: uinteger
documentation: The TrackUID of the Smooth FF/RW video in the paired
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EBML structure corresponding to this video track. See
[DivXTrickTrack].
27.27. TrickTrackSegmentUID Element
path: \Segment\Tracks\TrackEntry\TrickTrackSegmentUID
id: 0xC1
type: binary
documentation: The SegmentUID of the Segment containing the track
identified by TrickTrackUID. See [DivXTrickTrack].
27.28. TrickTrackFlag Element
path: \Segment\Tracks\TrackEntry\TrickTrackFlag
id: 0xC6
type: uinteger
documentation: Set to 1 if this video track is a Smooth FF/RW track.
If set to 1, MasterTrackUID and MasterTrackSegUID should must be
present and BlockGroups for this track must contain ReferenceFrame
structures. Otherwise, TrickTrackUID and TrickTrackSegUID must be
present if this track has a corresponding Smooth FF/RW track. See
[DivXTrickTrack].
27.29. TrickMasterTrackUID Element
path: \Segment\Tracks\TrackEntry\TrickMasterTrackUID
id: 0xC7
type: uinteger
documentation: The TrackUID of the video track in the paired EBML
structure that corresponds to this Smooth FF/RW track. See
[DivXTrickTrack].
27.30. TrickMasterTrackSegmentUID Element
path: \Segment\Tracks\TrackEntry\TrickMasterTrackSegmentUID
id: 0xC4
type: binary
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documentation: The SegmentUID of the Segment containing the track
identified by MasterTrackUID. See [DivXTrickTrack].
27.31. ContentSignature Element
path: \Segment\Tracks\TrackEntry\ContentEncodings\ContentEncoding\Co
ntentEncryption\ContentSignature
id: 0x47E3
type: binary
documentation: A cryptographic signature of the contents.
27.32. ContentSigKeyID Element
path: \Segment\Tracks\TrackEntry\ContentEncodings\ContentEncoding\Co
ntentEncryption\ContentSigKeyID
id: 0x47E4
type: binary
documentation: This is the ID of the private key the data was signed
with.
27.33. ContentSigAlgo Element
path: \Segment\Tracks\TrackEntry\ContentEncodings\ContentEncoding\Co
ntentEncryption\ContentSigAlgo
id: 0x47E5
type: uinteger
documentation: The algorithm used for the signature.
27.34. ContentSigHashAlgo Element
path: \Segment\Tracks\TrackEntry\ContentEncodings\ContentEncoding\Co
ntentEncryption\ContentSigHashAlgo
id: 0x47E6
type: uinteger
documentation: The hash algorithm used for the signature.
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27.35. CueRefCluster Element
path: \Segment\Cues\CuePoint\CueTrackPositions\CueReference\CueRefCl
uster
id: 0x97
type: uinteger
documentation: The Segment Position of the Cluster containing the
referenced Block.
27.36. CueRefNumber Element
path: \Segment\Cues\CuePoint\CueTrackPositions\CueReference\CueRefNu
mber
id: 0x535F
type: uinteger
documentation: Number of the referenced Block of Track X in the
specified Cluster.
27.37. CueRefCodecState Element
path: \Segment\Cues\CuePoint\CueTrackPositions\CueReference\CueRefCo
decState
id: 0xEB
type: uinteger
documentation: The Segment Position of the Codec State corresponding
to this referenced Element. 0 means that the data is taken from
the initial Track Entry.
27.38. FileReferral Element
path: \Segment\Attachments\AttachedFile\FileReferral
id: 0x4675
type: binary
documentation: A binary value that a track/codec can refer to when
the attachment is needed.
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27.39. FileUsedStartTime Element
path: \Segment\Attachments\AttachedFile\FileUsedStartTime
id: 0x4661
type: uinteger
documentation: The timestamp at which this optimized font attachment
comes into context, expressed in Segment Ticks which is based on
TimestampScale. See [DivXWorldFonts].
27.40. FileUsedEndTime Element
path: \Segment\Attachments\AttachedFile\FileUsedEndTime
id: 0x4662
type: uinteger
documentation: The timestamp at which this optimized font attachment
goes out of context, expressed in Segment Ticks which is based on
TimestampScale. See [DivXWorldFonts].
27.41. TagDefaultBogus Element
path: \Segment\Tags\Tag\+SimpleTag\TagDefaultBogus
id: 0x44B4
type: uinteger
documentation: A variant of the TagDefault element with a bogus
Element ID; see Section 8.1.8.1.2.4.
28. Normative References
[BCP47] Phillips, A., Ed. and M. Davis, Ed., "Tags for Identifying
Languages", DOI 10.17487/RFC5646, September 2009,
<https://www.rfc-editor.org/info/rfc5646>.
[Blowfish] Schneier, B., "The Blowfish Encryption Algorithm", 1993,
<https://www.schneier.com/academic/blowfish/>.
[BZIP2] Seward, J., "bzip2", 18 July 1996,
<https://sourceware.org/bzip2/>.
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[FIPS.197] US National Institute of Standards and Technology,
"Advanced Encryption Standard (AES)",
DOI 10.6028/NIST.FIPS.197, 26 November 2001,
<https://csrc.nist.gov/publications/detail/fips/197/
final>.
[FIPS.46-3]
US National Institute of Standards and Technology, "Data
Encryption Standard (DES)", FIPS PUB 46, 25 October 1999,
<https://csrc.nist.gov/publications/detail/fips/46/3/
archive/1999-10-25>.
[IANADomains]
"IANA Root Zone Database",
<https://www.iana.org/domains/root/db>.
[IANALangRegistry]
"IANA Language Subtag Registry", 28 February 2013,
<https://www.iana.org/assignments/language-subtag-
registry/language-subtag-registry>.
[ISO3166-1]
International Organization for Standardization, "Codes for
the representation of names of countries and their
subdivisions -- Part 1: Country code", ISO 3166-1:2020,
August 2020, <https://www.iso.org/standard/72482.html>.
[ISO639-2] United States Library Of Congress, "Codes for the
Representation of Names of Languages", ISO 639-2:1998, 21
December 2017, <https://www.loc.gov/standards/iso639-
2/php/code_list.php>.
[LZO] Tarreau, W., Rodgman, R., and M. Oberhumer,
"Lempel–Ziv–Oberhumer compression", 30 October 2018,
<https://www.kernel.org/doc/Documentation/lzo.txt>.
[MatroskaCodec]
Lhomme, S., Bunkus, M., and D. Rice, "Media Container
Codec Specifications", Work in Progress, Internet-Draft,
draft-ietf-cellar-codec-06, 12 April 2021,
<https://datatracker.ietf.org/doc/html/draft-ietf-cellar-
codec-06>.
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[MatroskaTags]
Lhomme, S., Bunkus, M., and D. Rice, "Matroska Media
Container Tag Specifications", Work in Progress, Internet-
Draft, draft-ietf-cellar-tags-06, 12 April 2021,
<https://datatracker.ietf.org/doc/html/draft-ietf-cellar-
tags-06>.
[RFC1851] Karn, P., Metzger, P., and W. Simpson, "The ESP Triple DES
Transform", RFC 1851, DOI 10.17487/RFC1851, September
1995, <https://www.rfc-editor.org/info/rfc1851>.
[RFC1950] Deutsch, P. and J-L. Gailly, "ZLIB Compressed Data Format
Specification version 3.3", RFC 1950,
DOI 10.17487/RFC1950, May 1996,
<https://www.rfc-editor.org/info/rfc1950>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC6838] Freed, N., Klensin, J., and T. Hansen, "Media Type
Specifications and Registration Procedures", BCP 13,
RFC 6838, DOI 10.17487/RFC6838, January 2013,
<https://www.rfc-editor.org/info/rfc6838>.
[RFC8081] Lilley, C., "The "font" Top-Level Media Type", RFC 8081,
DOI 10.17487/RFC8081, February 2017,
<https://www.rfc-editor.org/info/rfc8081>.
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/info/rfc8126>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8794] Lhomme, S., Rice, D., and M. Bunkus, "Extensible Binary
Meta Language", RFC 8794, DOI 10.17487/RFC8794, July 2020,
<https://www.rfc-editor.org/info/rfc8794>.
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[SP.800-38A]
US National Institute of Standards and Technology,
"Recommendation for Block Cipher Modes of Operation:
Methods and Techniques", DOI 10.6028/NIST.SP.800-38A, 1
December 2001,
<https://csrc.nist.gov/publications/detail/fips/197/
final>.
[Twofish] Schneier, B., Kelsey, J., Whiting, D., Wagner, D., Hall,
C., and N. Ferguson, "Twofish: A 128-Bit Block Cipher", 15
June 1998, <https://www.schneier.com/academic/twofish/>.
[WebVTT] Pieters, S., Pfeiffer, S., Ed., Jägenstedt, P., and I.
Hickson, "WebVTT Cue Identifier", 4 April 2019,
<https://www.w3.org/TR/webvtt1/#webvtt-cue-identifier>.
29. Informative References
[AVIFormat]
Microsoft, "AVI RIFF File Reference", 31 May 2018,
<https://docs.microsoft.com/en-
us/windows/win32/directshow/avi-riff-file-reference>.
[DivXTrickTrack]
"DivX Trick Track Extensions", 14 December 2010,
<http://web.archive.org/web/20101222001148/
http://labs.divx.com/node/16601>.
[DivXWorldFonts]
"DivX World Fonts Extensions", 14 December 2010,
<http://web.archive.org/web/20110214132246/
http://labs.divx.com/node/16602>.
[FourCC-RGB]
Silicon.dk ApS, "RGB Pixel Format FourCCs",
<https://www.fourcc.org/rgb.php>.
[FourCC-YUV]
Silicon.dk ApS, "YUV Pixel Format FourCCs",
<https://www.fourcc.org/yuv.php>.
[MCF] "Media Container Format", 17 July 2002,
<http://mukoli.free.fr/mcf/mcf.html>.
[RFC3533] Pfeiffer, S., "The Ogg Encapsulation Format Version 0",
RFC 3533, DOI 10.17487/RFC3533, May 2003,
<https://www.rfc-editor.org/info/rfc3533>.
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Authors' Addresses
Steve Lhomme
Email: slhomme@matroska.org
Moritz Bunkus
Email: moritz@bunkus.org
Dave Rice
Email: dave@dericed.com
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