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nested elements and deeper toc
cellar S. Lhomme
Internet-Draft
Intended status: Standards Track M. Bunkus
Expires: January 26, 2019
D. Rice
July 25, 2018
Matroska Specifications
draft-lhomme-cellar-matroska-04
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 January 26, 2019.
Copyright Notice
Copyright (c) 2018 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 Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 6
2. Status of this document . . . . . . . . . . . . . . . . . . . 7
3. Security Considerations . . . . . . . . . . . . . . . . . . . 7
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8
5. Notation and Conventions . . . . . . . . . . . . . . . . . . 8
6. Basis in EBML . . . . . . . . . . . . . . . . . . . . . . . . 8
6.1. Added Constraints on EBML . . . . . . . . . . . . . . . . 8
6.2. Matroska Design . . . . . . . . . . . . . . . . . . . . . 9
6.2.1. Language Codes . . . . . . . . . . . . . . . . . . . 9
6.2.2. Physical Types . . . . . . . . . . . . . . . . . . . 9
6.2.3. Block Structure . . . . . . . . . . . . . . . . . . . 10
6.2.3.1. Block Header . . . . . . . . . . . . . . . . . . 10
6.2.3.2. Block Header Flags . . . . . . . . . . . . . . . 11
6.2.4. Lacing . . . . . . . . . . . . . . . . . . . . . . . 11
6.2.4.1. Xiph lacing . . . . . . . . . . . . . . . . . . . 12
6.2.4.2. EBML lacing . . . . . . . . . . . . . . . . . . . 12
6.2.4.3. Fixed-size lacing . . . . . . . . . . . . . . . . 13
6.2.4.4. SimpleBlock Structure . . . . . . . . . . . . . . 13
6.2.4.4.1. SimpleBlock Header . . . . . . . . . . . . . 14
6.2.4.4.2. SimpleBlock Header Flags . . . . . . . . . . 14
6.2.4.5. Laced Data . . . . . . . . . . . . . . . . . . . 14
7. Matroska Structure . . . . . . . . . . . . . . . . . . . . . 15
8. Matroska Schema . . . . . . . . . . . . . . . . . . . . . . . 23
8.1. Matroska Additions to Schema Element Attributes . . . . . 23
8.2. Matroska Schema Element Definitions . . . . . . . . . . . 24
8.2.1. EBMLMaxIDLength Element . . . . . . . . . . . . . . . 24
8.2.2. EBMLMaxSizeLength Element . . . . . . . . . . . . . . 24
8.2.3. Segment Element . . . . . . . . . . . . . . . . . . . 25
8.2.3.1. SeekHead Element . . . . . . . . . . . . . . . . 25
8.2.3.1.1. Seek Element . . . . . . . . . . . . . . . . 25
8.2.3.1.1.1. SeekID Element . . . . . . . . . . . . . 26
8.2.3.1.1.2. SeekPosition Element . . . . . . . . . . 26
8.2.3.2. Info Element . . . . . . . . . . . . . . . . . . 27
8.2.3.2.1. SegmentUID Element . . . . . . . . . . . . . 27
8.2.3.2.2. SegmentFilename Element . . . . . . . . . . . 27
8.2.3.2.3. PrevUID Element . . . . . . . . . . . . . . . 28
8.2.3.2.4. PrevFilename Element . . . . . . . . . . . . 28
8.2.3.2.5. NextUID Element . . . . . . . . . . . . . . . 29
8.2.3.2.6. NextFilename Element . . . . . . . . . . . . 29
8.2.3.2.7. SegmentFamily Element . . . . . . . . . . . . 30
8.2.3.2.8. ChapterTranslate Element . . . . . . . . . . 30
8.2.3.2.8.1. ChapterTranslateEditionUID Element . . . 30
8.2.3.2.8.2. ChapterTranslateCodec Element . . . . . . 31
8.2.3.2.8.3. ChapterTranslateID Element . . . . . . . 31
8.2.3.2.9. TimestampScale Element . . . . . . . . . . . 32
8.2.3.2.10. Duration Element . . . . . . . . . . . . . . 32
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8.2.3.2.11. DateUTC Element . . . . . . . . . . . . . . . 32
8.2.3.2.12. Title Element . . . . . . . . . . . . . . . . 33
8.2.3.2.13. MuxingApp Element . . . . . . . . . . . . . . 33
8.2.3.2.14. WritingApp Element . . . . . . . . . . . . . 34
8.2.3.3. Cluster Element . . . . . . . . . . . . . . . . . 34
8.2.3.3.1. Timestamp Element . . . . . . . . . . . . . . 34
8.2.3.3.2. SilentTracks Element . . . . . . . . . . . . 35
8.2.3.3.2.1. SilentTrackNumber Element . . . . . . . . 35
8.2.3.3.3. Position Element . . . . . . . . . . . . . . 35
8.2.3.3.4. PrevSize Element . . . . . . . . . . . . . . 36
8.2.3.3.5. SimpleBlock Element . . . . . . . . . . . . . 36
8.2.3.3.6. BlockGroup Element . . . . . . . . . . . . . 37
8.2.3.3.6.1. Block Element . . . . . . . . . . . . . . 37
8.2.3.3.6.2. BlockVirtual Element . . . . . . . . . . 37
8.2.3.3.6.3. BlockAdditions Element . . . . . . . . . 38
8.2.3.3.6.4. BlockDuration Element . . . . . . . . . . 39
8.2.3.3.6.5. ReferencePriority Element . . . . . . . . 40
8.2.3.3.6.6. ReferenceBlock Element . . . . . . . . . 40
8.2.3.3.6.7. ReferenceVirtual Element . . . . . . . . 41
8.2.3.3.6.8. CodecState Element . . . . . . . . . . . 41
8.2.3.3.6.9. DiscardPadding Element . . . . . . . . . 41
8.2.3.3.6.10. Slices Element . . . . . . . . . . . . . 42
8.2.3.3.6.11. ReferenceFrame Element . . . . . . . . . 45
8.2.3.3.7. EncryptedBlock Element . . . . . . . . . . . 46
8.2.3.4. Tracks Element . . . . . . . . . . . . . . . . . 46
8.2.3.4.1. TrackEntry Element . . . . . . . . . . . . . 47
8.2.3.4.1.1. TrackNumber Element . . . . . . . . . . . 47
8.2.3.4.1.2. TrackUID Element . . . . . . . . . . . . 47
8.2.3.4.1.3. TrackType Element . . . . . . . . . . . . 48
8.2.3.4.1.4. FlagEnabled Element . . . . . . . . . . . 48
8.2.3.4.1.5. FlagDefault Element . . . . . . . . . . . 49
8.2.3.4.1.6. FlagForced Element . . . . . . . . . . . 49
8.2.3.4.1.7. FlagLacing Element . . . . . . . . . . . 50
8.2.3.4.1.8. MinCache Element . . . . . . . . . . . . 50
8.2.3.4.1.9. MaxCache Element . . . . . . . . . . . . 51
8.2.3.4.1.10. DefaultDuration Element . . . . . . . . . 51
8.2.3.4.1.11. DefaultDecodedFieldDuration Element . . . 51
8.2.3.4.1.12. TrackTimestampScale Element . . . . . . . 52
8.2.3.4.1.13. TrackOffset Element . . . . . . . . . . . 52
8.2.3.4.1.14. MaxBlockAdditionID Element . . . . . . . 53
8.2.3.4.1.15. Name Element . . . . . . . . . . . . . . 53
8.2.3.4.1.16. Language Element . . . . . . . . . . . . 54
8.2.3.4.1.17. LanguageIETF Element . . . . . . . . . . 54
8.2.3.4.1.18. CodecID Element . . . . . . . . . . . . . 54
8.2.3.4.1.19. CodecPrivate Element . . . . . . . . . . 55
8.2.3.4.1.20. CodecName Element . . . . . . . . . . . . 55
8.2.3.4.1.21. AttachmentLink Element . . . . . . . . . 55
8.2.3.4.1.22. CodecSettings Element . . . . . . . . . . 56
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8.2.3.4.1.23. CodecInfoURL Element . . . . . . . . . . 56
8.2.3.4.1.24. CodecDownloadURL Element . . . . . . . . 57
8.2.3.4.1.25. CodecDecodeAll Element . . . . . . . . . 57
8.2.3.4.1.26. TrackOverlay Element . . . . . . . . . . 57
8.2.3.4.1.27. CodecDelay Element . . . . . . . . . . . 58
8.2.3.4.1.28. SeekPreRoll Element . . . . . . . . . . . 58
8.2.3.4.1.29. TrackTranslate Element . . . . . . . . . 59
8.2.3.4.1.30. Video Element . . . . . . . . . . . . . . 60
8.2.3.4.1.31. Audio Element . . . . . . . . . . . . . . 81
8.2.3.4.1.32. TrackOperation Element . . . . . . . . . 83
8.2.3.4.1.33. TrickTrackUID Element . . . . . . . . . . 86
8.2.3.4.1.34. TrickTrackSegmentUID Element . . . . . . 86
8.2.3.4.1.35. TrickTrackFlag Element . . . . . . . . . 87
8.2.3.4.1.36. TrickMasterTrackUID Element . . . . . . . 87
8.2.3.4.1.37. TrickMasterTrackSegmentUID Element . . . 88
8.2.3.4.1.38. ContentEncodings Element . . . . . . . . 88
8.2.3.5. Cues Element . . . . . . . . . . . . . . . . . . 94
8.2.3.5.1. CuePoint Element . . . . . . . . . . . . . . 95
8.2.3.5.1.1. CueTime Element . . . . . . . . . . . . . 95
8.2.3.5.1.2. CueTrackPositions Element . . . . . . . . 95
8.2.3.6. Attachments Element . . . . . . . . . . . . . . . 100
8.2.3.6.1. AttachedFile Element . . . . . . . . . . . . 101
8.2.3.6.1.1. FileDescription Element . . . . . . . . . 101
8.2.3.6.1.2. FileName Element . . . . . . . . . . . . 101
8.2.3.6.1.3. FileMimeType Element . . . . . . . . . . 102
8.2.3.6.1.4. FileData Element . . . . . . . . . . . . 102
8.2.3.6.1.5. FileUID Element . . . . . . . . . . . . . 103
8.2.3.6.1.6. FileReferral Element . . . . . . . . . . 103
8.2.3.6.1.7. FileUsedStartTime Element . . . . . . . . 103
8.2.3.6.1.8. FileUsedEndTime Element . . . . . . . . . 104
8.2.3.7. Chapters Element . . . . . . . . . . . . . . . . 104
8.2.3.7.1. EditionEntry Element . . . . . . . . . . . . 105
8.2.3.7.1.1. EditionUID Element . . . . . . . . . . . 105
8.2.3.7.1.2. EditionFlagHidden Element . . . . . . . . 105
8.2.3.7.1.3. EditionFlagDefault Element . . . . . . . 106
8.2.3.7.1.4. EditionFlagOrdered Element . . . . . . . 106
8.2.3.7.1.5. ChapterAtom Element . . . . . . . . . . . 107
8.2.3.8. Tags Element . . . . . . . . . . . . . . . . . . 116
8.2.3.8.1. Tag Element . . . . . . . . . . . . . . . . . 116
8.2.3.8.1.1. Targets Element . . . . . . . . . . . . . 117
8.2.3.8.1.2. SimpleTag Element . . . . . . . . . . . . 119
9. Matroska Element Ordering . . . . . . . . . . . . . . . . . . 122
9.1. Top-Level Elements . . . . . . . . . . . . . . . . . . . 122
9.2. CRC-32 . . . . . . . . . . . . . . . . . . . . . . . . . 123
9.3. SeekHead . . . . . . . . . . . . . . . . . . . . . . . . 123
9.4. Cues (index) . . . . . . . . . . . . . . . . . . . . . . 123
9.5. Info . . . . . . . . . . . . . . . . . . . . . . . . . . 124
9.6. Chapters Element . . . . . . . . . . . . . . . . . . . . 124
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9.7. Attachments . . . . . . . . . . . . . . . . . . . . . . . 124
9.8. Tags . . . . . . . . . . . . . . . . . . . . . . . . . . 124
9.9. Optimum layout from a muxer . . . . . . . . . . . . . . . 125
9.10. Optimum layout after editing tags . . . . . . . . . . . . 125
9.11. Optimum layout with Cues at the front . . . . . . . . . . 125
9.12. Cluster Timestamp . . . . . . . . . . . . . . . . . . . . 126
10. Chapters . . . . . . . . . . . . . . . . . . . . . . . . . . 126
10.1. Edition and Chapter Flags . . . . . . . . . . . . . . . 126
10.1.1. Chapter Flags . . . . . . . . . . . . . . . . . . . 126
10.1.2. Edition Flags . . . . . . . . . . . . . . . . . . . 127
10.1.2.1. EditionFlagHidden . . . . . . . . . . . . . . . 127
10.1.2.2. EditionFlagDefault . . . . . . . . . . . . . . . 127
10.1.2.3. EditionFlagOrdered . . . . . . . . . . . . . . . 127
10.1.2.3.1. Ordered-Edition and Matroska Segment-Linking 128
10.2. Menu features . . . . . . . . . . . . . . . . . . . . . 128
10.2.1. Matroska Script (0) . . . . . . . . . . . . . . . . 129
10.2.2. DVD menu (1) . . . . . . . . . . . . . . . . . . . . 129
10.3. Example 1 : basic chaptering . . . . . . . . . . . . . . 130
10.4. Example 2 : nested chapters . . . . . . . . . . . . . . 132
10.4.1. The Micronauts "Bleep To Bleep" . . . . . . . . . . 133
11. Attachments . . . . . . . . . . . . . . . . . . . . . . . . . 136
11.1. Cover Art . . . . . . . . . . . . . . . . . . . . . . . 136
12. Cues . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
12.1. Recommendations . . . . . . . . . . . . . . . . . . . . 137
13. Matroska Streaming . . . . . . . . . . . . . . . . . . . . . 138
13.1. File Access . . . . . . . . . . . . . . . . . . . . . . 138
13.2. Livestreaming . . . . . . . . . . . . . . . . . . . . . 138
14. Menu Specifications . . . . . . . . . . . . . . . . . . . . . 139
14.1. Requirements . . . . . . . . . . . . . . . . . . . . . . 139
14.1.1. Highlights/Hotspots . . . . . . . . . . . . . . . . 139
14.1.2. Playback features . . . . . . . . . . . . . . . . . 140
14.1.3. Player requirements . . . . . . . . . . . . . . . . 141
14.2. Working Graph . . . . . . . . . . . . . . . . . . . . . 141
15. Unknown elements . . . . . . . . . . . . . . . . . . . . . . 141
16. Default Values . . . . . . . . . . . . . . . . . . . . . . . 141
17. DefaultDecodedFieldDuration . . . . . . . . . . . . . . . . . 141
18. Encryption . . . . . . . . . . . . . . . . . . . . . . . . . 142
19. Image cropping . . . . . . . . . . . . . . . . . . . . . . . 142
20. Matroska versioning . . . . . . . . . . . . . . . . . . . . . 143
21. MIME Types . . . . . . . . . . . . . . . . . . . . . . . . . 144
22. Segment Position . . . . . . . . . . . . . . . . . . . . . . 144
22.1. Segment Position Exception . . . . . . . . . . . . . . . 144
22.2. Example of Segment Position . . . . . . . . . . . . . . 144
23. Linked Segments . . . . . . . . . . . . . . . . . . . . . . . 145
23.1. Hard Linking . . . . . . . . . . . . . . . . . . . . . . 145
23.2. Medium Linking . . . . . . . . . . . . . . . . . . . . . 146
23.3. Soft Linking . . . . . . . . . . . . . . . . . . . . . . 146
24. Track Flags . . . . . . . . . . . . . . . . . . . . . . . . . 147
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24.1. Default flag . . . . . . . . . . . . . . . . . . . . . . 147
24.2. Forced flag . . . . . . . . . . . . . . . . . . . . . . 147
24.3. Track Operation . . . . . . . . . . . . . . . . . . . . 147
24.4. Overlay Track . . . . . . . . . . . . . . . . . . . . . 148
24.5. Multi-planar and 3D videos . . . . . . . . . . . . . . . 148
25. Timestamps . . . . . . . . . . . . . . . . . . . . . . . . . 149
25.1. Timestamp Types . . . . . . . . . . . . . . . . . . . . 149
25.2. Block Timestamps . . . . . . . . . . . . . . . . . . . . 149
25.3. Raw Timestamp . . . . . . . . . . . . . . . . . . . . . 149
25.4. TimestampScale . . . . . . . . . . . . . . . . . . . . . 149
25.5. TimestampScale Rounding . . . . . . . . . . . . . . . . 150
25.6. TrackTimestampScale . . . . . . . . . . . . . . . . . . 152
26.1. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 153
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 154
1. Introduction
Matroska aims to become THE standard of multimedia container formats.
It was derived from a project called MCF [1], but differentiates from
it significantly because it is based on EBML [2] (Extensible Binary
Meta Language), 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:
o It is NOT a video or audio compression format (codec)
o 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:
o Fast seeking in the file
o Chapter entries
o Full metadata (tags) support
o Selectable subtitle/audio/video streams
o Modularly expandable
o Error resilience (can recover playback even when the stream is
damaged)
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o Streamable over the internet and local networks (HTTP, CIFS, FTP,
etc)
o 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.
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 [3].
But since it's quite complete it is used as a reference for the
development of libmatroska. Legacy versions of the specification can
be found here [4] (PDF doc by Alexander Noe -- outdated).
For a simplified diagram of the layout of a Matroska file, see the
Diagram page [5].
A more refined and detailed version of the EBML specifications is
being worked on here [6].
The table found below is now generated from the "source" of the
Matroska specification. This XML file [7] is also used to generate
the semantic data used in libmatroska and libmatroska2. We encourage
anyone to use and monitor its changes so your code is spec-proof and
always up to date.
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:
o 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.
o A "Matroska Attachment" with an inaccurate mime-type.
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4. IANA Considerations
To be determined.
5. Notation and Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [8].
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 "Matroska Reader" is a data parser that
interprets the semantics of a Matroska document and creates a way for
programs to use "Matroska".
"Matroska Player": A "Matroska Player" is a "Matroska Reader" with a
primary purpose of playing audiovisual files, including "Matroska"
documents.
6. Basis in EBML
Matroska is a Document Type of EBML (Extensible Binary Meta
Language). This specification is dependent on the EBML Specification
[9]. For an understanding of Matroska's EBML Schema, see in
particular the sections of the EBML Specification covering EBML
Element Types [10], EBML Schema [11], and EBML Structure [12].
6.1. Added Constraints on EBML
As an EBML Document Type, Matroska adds the following constraints to
the EBML specification.
o The "docType" of the "EBML Header" MUST be 'matroska'.
o The "EBMLMaxIDLength" of the "EBML Header" MUST be "4".
o The "EBMLMaxSizeLength" of the "EBML Header" MUST be between "1"
and "8" inclusive.
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6.2. Matroska Design
All top-levels elements (Segment and direct sub-elements) are coded
on 4 octets, i.e. class D elements.
6.2.1. Language Codes
Matroska from version 1 through 3 uses language codes that can be
either the 3 letters bibliographic ISO-639-2 [13] form (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 "ISO 639-2" or BCP 47 [14] 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 as used for internet domains [15].
6.2.2. 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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+----------------------+--------------+-----------+-----------------+
| ChapterPhysicalEquiv | Audio | Video | Comment |
+----------------------+--------------+-----------+-----------------+
| 70 | SET / | SET / | the collection |
| | PACKAGE | PACKAGE | of different |
| | | | media |
| 60 | CD / 12" / | DVD / VHS | the physical |
| | 10" / 7" / | / | medium like a |
| | TAPE / | LASERDISC | CD or a DVD |
| | MINIDISC / | | |
| | DAT | | |
| 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 |
+----------------------+--------------+-----------+-----------------+
6.2.3. Block Structure
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 MAY NOT be consecutive. But a frame
with a past timestamp MUST reference a frame already known, otherwise
it's considered bad/void.
There can be many Blocks in a BlockGroup provided they all have the
same timestamp. It is used with different parts of a frame with
different priorities.
6.2.3.1. Block Header
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+--------+--------+-------------------------------------------------+
| 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) |
+--------+--------+-------------------------------------------------+
6.2.3.2. 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 |
+--------+-----+--------+-------------------------------------------+
6.2.4. 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). There are 3 types of lacing:
1. Xiph, inspired by what is found in the Ogg container
2. EBML, which is the same with sizes coded differently
3. fixed-size, where the size is not coded
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. They will then be stored in the same
block as follows:
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6.2.4.1. Xiph lacing
o Block head (with lacing bits set to 01)
o Lacing head: Number of frames in the lace -1, i.e. 2 (the 800 and
500 octets one)
o Lacing sizes: only the 2 first ones will be coded, 800 gives
255;255;255;35, 500 gives 255;245. The size of the last frame is
deduced from the total size of the Block.
o Data in frame 1
o Data in frame 2
o Data in frame 3
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.
6.2.4.2. EBML lacing
In this case, the size is not coded as blocks of 255 bytes, but as a
difference with the previous size and this size is coded as in EBML.
The first size in the lace is unsigned as in EBML. The others use a
range shifting to get a sign on each value:
+----------------------------------+--------------------------------+
| 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 xxxx | value -(2^20-1) to 2^20-1 |
| 0001 xxxx xxxx xxxx xxxx xxxx | value -(2^27-1) to 2^27-1 |
| xxxx xxxx | |
| 0000 1xxx xxxx xxxx xxxx xxxx | value -(2^34-1) to 2^34-1 |
| xxxx xxxx xxxx xxxx | |
| 0000 01xx xxxx xxxx xxxx xxxx | value -(2^41-1) to 2^41-1 |
| xxxx xxxx xxxx xxxx xxxx xxxx | |
| 0000 001x xxxx xxxx xxxx xxxx | value -(2^48-1) to 2^48-1 |
| xxxx xxxx xxxx xxxx xxxx xxxx | |
| xxxx xxxx | |
+----------------------------------+--------------------------------+
o Block head (with lacing bits set to 11)
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o Lacing head: Number of frames in the lace -1, i.e. 2 (the 800 and
500 octets one)
o Lacing sizes: only the 2 first ones will be coded, 800 gives 0x320
0x4000 = 0x4320, 500 is coded as -300 : - 0x12C + 0x1FFF + 0x4000
= 0x5ED3. The size of the last frame is deduced from the total
size of the Block.
o Data in frame 1
o Data in frame 2
o Data in frame 3
6.2.4.3. Fixed-size lacing
In this case, only the number of frames in the lace is saved, the
size of each frame is deduced from the total size of the Block. For
example, for 3 frames of 800 octets each:
o Block head (with lacing bits set to 10)
o Lacing head: Number of frames in the lace -1, i.e. 2
o Data in frame 1
o Data in frame 2
o Data in frame 3
6.2.4.4. SimpleBlock Structure
The "SimpleBlock" is inspired by the Section 6.2.3. 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 MAY NOT be consecutive. But a frame
with a past timestamp MUST reference a frame already known, otherwise
it's considered bad/void.
There can be many "Block Elements" in a "BlockGroup" provided they
all have the same timestamp. It is used with different parts of a
frame with different priorities.
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6.2.4.4.1. 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) |
+--------+--------+-------------------------------------------------+
6.2.4.4.2. 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 |
| | | | * 11 : EBML lacing |
| | | | * 10 : fixed-size lacing |
| 0x03+ | 7 | - | Discardable, the frames of the Block can |
| | | | be discarded during playing if needed |
+--------+-----+--------+-------------------------------------------+
6.2.4.5. Laced Data
When lacing bit is set.
+--------+--------+-------------------------------------------------+
| Offset | Player | Description |
+--------+--------+-------------------------------------------------+
| 0x00 | MUST | Number of frames in the lace-1 (uint8) |
| 0x01 / | MUST* | Lace-coded size of each frame of the lace, |
| 0xXX | | except for the last one (multiple uint8). *This |
| | | is not used with Fixed-size lacing as it is |
| | | calculated automatically from (total size of |
| | | lace) / (number of frames in lace). |
+--------+--------+-------------------------------------------------+
For (possibly) Laced Data
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+--------+--------+--------------------------+
| Offset | Player | Description |
+--------+--------+--------------------------+
| 0x00 | MUST | Consecutive laced frames |
+--------+--------+--------------------------+
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:
o "EBML Header"
o "Segment"
A more complex Matroska file consisting of an "EBML Stream"
(consisting of two "EBML Documents") could be represented like this:
o "EBML Header"
o "Segment"
o "EBML Header"
o "Segment"
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.
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+-------------+
| EBML Header |
+---------------------------+
| Segment | SeekHead |
| |-------------|
| | Info |
| |-------------|
| | Tracks |
| |-------------|
| | Chapters |
| |-------------|
| | Cluster |
| |-------------|
| | Cues |
| |-------------|
| | Attachments |
| |-------------|
| | Tags |
+---------------------------+
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 |
+--------------------------------+
Representation of a SeekHead Element.
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".
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+-------------------------+
| Info | SegmentUID |
| |------------------|
| | SegmentFilename |
| |------------------|
| | PrevUID |
| |------------------|
| | PrevFilename |
| |------------------|
| | NextUID |
| |------------------|
| | NextFilename |
| |------------------|
| | SegmentFamily |
| |------------------|
| | ChapterTranslate |
| |------------------|
| | TimestampScale |
| |------------------|
| | Duration |
| |------------------|
| | DateUTC |
| |------------------|
| | Title |
| |------------------|
| | MuxingApp |
| |------------------|
| | WritingApp |
|-------------------------|
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.
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 |
|--------------------------------------------------------|
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 |--------------------|
| | | EditionFlagHidden |
| | |--------------------|
| | | EditionFlagDefault |
| | |--------------------|
| | | EditionFlagOrdered |
| | |--------------------------------+
| | | ChapterAtom | ChapterUID |
| | | |------------------|
| | | | ChapterStringUID |
| | | |------------------|
| | | | ChapterTimeStart |
| | | |------------------|
| | | | ChapterTimeEnd |
| | | |------------------|
| | | | ChapterFlagHidden |
| | | |---------------------------------+
| | | | ChapterDisplay | ChapString |
| | | | |--------------|
| | | | | ChapLanguage |
+--------------------------------------------------------------------+
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 |
| |----------------|
| | EncryptedBlock |
+--------------------------+
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 |
+----------------------------------+
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".
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
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"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 |
+-------------------------------------+
Representation of a Cues Element and two levels of its Descendant
Elements.
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.
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+------------------------------------------------+
| Attachments | AttachedFile | FileDescription |
| | |-------------------|
| | | FileName |
| | |-------------------|
| | | FileMimeType |
| | |-------------------|
| | | FileData |
| | |-------------------|
| | | FileUID |
| | |-------------------|
| | | FileName |
| | |-------------------|
| | | FileReferral |
| | |-------------------|
| | | FileUsedStartTime |
| | |-------------------|
| | | FileUsedEndTime |
+------------------------------------------------+
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 |
+-------------------------------------------+
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.
8.1. Matroska Additions to Schema Element Attributes
In addition to the EBML Schema definition provided by the EBML
Specification, Matroska adds the following additional attributes:
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+-----------+----------+--------------------------------------------+
| attribute | required | definition |
| name | | |
+-----------+----------+--------------------------------------------+
| webm | No | A boolean to express if the Matroska |
| | | Element is also supported within version 2 |
| | | of the "webm" specification. Please |
| | | consider the webm specification [16] as |
| | | the authoritative on "webm". |
+-----------+----------+--------------------------------------------+
8.2. Matroska Schema Element Definitions
Here the definition of each Matroska Element is provided.
% concatenate with Matroska EBML Schema converted to markdown %
8.2.1. EBMLMaxIDLength Element
name: "EBMLMaxIDLength"
path: "1*1(\EBML\EBMLMaxIDLength)"
id: "0x42F2"
minOccurs: "1"
maxOccurs: "1"
range: "4"
default: "4"
type: "uinteger"
8.2.2. EBMLMaxSizeLength Element
name: "EBMLMaxSizeLength"
path: "1*1(\EBML\EBMLMaxSizeLength)"
id: "0x42F3"
minOccurs: "1"
maxOccurs: "1"
range: "1-8"
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default: "8"
type: "uinteger"
8.2.3. Segment Element
name: "Segment"
path: "1*1(\Segment)"
id: "0x18538067"
minOccurs: "1"
maxOccurs: "1"
type: "master"
unknownsizeallowed: "1"
minver: "1"
documentation: The Root Element that contains all other Top-Level
Elements (Elements defined only at Level 1). A Matroska file is
composed of 1 Segment.
8.2.3.1. SeekHead Element
name: "SeekHead"
path: "0*2(\Segment\SeekHead)"
id: "0x114D9B74"
maxOccurs: "2"
type: "master"
minver: "1"
documentation: Contains the Segment Position of other Top-Level
Elements.
8.2.3.1.1. Seek Element
name: "Seek"
path: "1*(\Segment\SeekHead\Seek)"
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id: "0x4DBB"
minOccurs: "1"
type: "master"
minver: "1"
documentation: Contains a single seek entry to an EBML Element.
8.2.3.1.1.1. SeekID Element
name: "SeekID"
path: "1*1(\Segment\SeekHead\Seek\SeekID)"
id: "0x53AB"
minOccurs: "1"
maxOccurs: "1"
type: "binary"
minver: "1"
documentation: The binary ID corresponding to the Element name.
8.2.3.1.1.2. SeekPosition Element
name: "SeekPosition"
path: "1*1(\Segment\SeekHead\Seek\SeekPosition)"
id: "0x53AC"
minOccurs: "1"
maxOccurs: "1"
type: "uinteger"
minver: "1"
documentation: The Segment Position of the Element.
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8.2.3.2. Info Element
name: "Info"
path: "1*(\Segment\Info)"
id: "0x1549A966"
minOccurs: "1"
type: "master"
minver: "1"
definition: Contains general information about the Segment.
8.2.3.2.1. SegmentUID Element
name: "SegmentUID"
path: "0*1(\Segment\Info\SegmentUID)"
id: "0x73A4"
maxOccurs: "1"
range: "not 0"
size: "16"
type: "binary"
minver: "1"
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.
8.2.3.2.2. SegmentFilename Element
name: "SegmentFilename"
path: "0*1(\Segment\Info\SegmentFilename)"
id: "0x7384"
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maxOccurs: "1"
type: "utf-8"
minver: "1"
definition: A filename corresponding to this Segment.
8.2.3.2.3. PrevUID Element
name: "PrevUID"
path: "0*1(\Segment\Info\PrevUID)"
id: "0x3CB923"
maxOccurs: "1"
size: "16"
type: "binary"
minver: "1"
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.
8.2.3.2.4. PrevFilename Element
name: "PrevFilename"
path: "0*1(\Segment\Info\PrevFilename)"
id: "0x3C83AB"
maxOccurs: "1"
type: "utf-8"
minver: "1"
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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.
8.2.3.2.5. NextUID Element
name: "NextUID"
path: "0*1(\Segment\Info\NextUID)"
id: "0x3EB923"
maxOccurs: "1"
size: "16"
type: "binary"
minver: "1"
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.
8.2.3.2.6. NextFilename Element
name: "NextFilename"
path: "0*1(\Segment\Info\NextFilename)"
id: "0x3E83BB"
maxOccurs: "1"
type: "utf-8"
minver: "1"
definition: A filename corresponding to the file of the next Linked
Segment.
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usage notes: Provision of the next filename is for display
convenience, but NextUID SHOULD be considered authoritative for
identifying the Next Segment.
8.2.3.2.7. SegmentFamily Element
name: "SegmentFamily"
path: "0*(\Segment\Info\SegmentFamily)"
id: "0x4444"
size: "16"
type: "binary"
minver: "1"
definition: A randomly generated unique ID that all Segments of a
Linked Segment MUST share (128 bits).
usage notes: If the Segment is a part of a Linked Segment that uses
Soft Linking then this Element is REQUIRED.
8.2.3.2.8. ChapterTranslate Element
name: "ChapterTranslate"
path: "0*(\Segment\Info\ChapterTranslate)"
id: "0x6924"
type: "master"
minver: "1"
documentation: A tuple of corresponding ID used by chapter codecs to
represent this Segment.
8.2.3.2.8.1. ChapterTranslateEditionUID Element
name: "ChapterTranslateEditionUID"
path: "0*(\Segment\Info\ChapterTranslate\ChapterTranslateEditionUID)"
id: "0x69FC"
type: "uinteger"
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minver: "1"
documentation: Specify an edition UID on which this correspondance
applies. When not specified, it means for all editions found in the
Segment.
8.2.3.2.8.2. ChapterTranslateCodec Element
name: "ChapterTranslateCodec"
path: "1*1(\Segment\Info\ChapterTranslate\ChapterTranslateCodec)"
id: "0x69BF"
minOccurs: "1"
maxOccurs: "1"
type: "uinteger"
minver: "1"
documentation: The chapter codec
8.2.3.2.8.3. ChapterTranslateID Element
name: "ChapterTranslateID"
path: "1*1(\Segment\Info\ChapterTranslate\ChapterTranslateID)"
id: "0x69A5"
minOccurs: "1"
maxOccurs: "1"
type: "binary"
minver: "1"
documentation: The binary value used to represent this Segment in the
chapter codec data. The format depends on the ChapProcessCodecID
used.
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8.2.3.2.9. TimestampScale Element
name: "TimestampScale"
path: "1*1(\Segment\Info\TimestampScale)"
id: "0x2AD7B1"
minOccurs: "1"
maxOccurs: "1"
range: "not 0"
default: "1000000"
type: "uinteger"
minver: "1"
documentation: Timestamp scale in nanoseconds (1.000.000 means all
timestamps in the Segment are expressed in milliseconds).
8.2.3.2.10. Duration Element
name: "Duration"
path: "0*1(\Segment\Info\Duration)"
id: "0x4489"
maxOccurs: "1"
range: "> 0x0p+0"
type: "float"
minver: "1"
definition: Duration of the Segment in nanoseconds based on
TimestampScale.
8.2.3.2.11. DateUTC Element
name: "DateUTC"
path: "0*1(\Segment\Info\DateUTC)"
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id: "0x4461"
maxOccurs: "1"
type: "date"
minver: "1"
documentation: The date and time that the Segment was created by the
muxing application or library.
8.2.3.2.12. Title Element
name: "Title"
path: "0*1(\Segment\Info\Title)"
id: "0x7BA9"
maxOccurs: "1"
type: "utf-8"
minver: "1"
documentation: General name of the Segment.
8.2.3.2.13. MuxingApp Element
name: "MuxingApp"
path: "1*1(\Segment\Info\MuxingApp)"
id: "0x4D80"
minOccurs: "1"
maxOccurs: "1"
type: "utf-8"
minver: "1"
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.
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8.2.3.2.14. WritingApp Element
name: "WritingApp"
path: "1*1(\Segment\Info\WritingApp)"
id: "0x5741"
minOccurs: "1"
maxOccurs: "1"
type: "utf-8"
minver: "1"
definition: Writing application (example: "mkvmerge-0.3.3").
usage notes: Include the full name of the application followed by the
version number.
8.2.3.3. Cluster Element
name: "Cluster"
path: "0*(\Segment\Cluster)"
id: "0x1F43B675"
type: "master"
unknownsizeallowed: "1"
minver: "1"
documentation: The Top-Level Element containing the (monolithic)
Block structure.
8.2.3.3.1. Timestamp Element
name: "Timestamp"
path: "1*1(\Segment\Cluster\Timestamp)"
id: "0xE7"
minOccurs: "1"
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maxOccurs: "1"
type: "uinteger"
minver: "1"
documentation: Absolute timestamp of the cluster (based on
TimestampScale).
8.2.3.3.2. SilentTracks Element
name: "SilentTracks"
path: "0*1(\Segment\Cluster\SilentTracks)"
id: "0x5854"
maxOccurs: "1"
type: "master"
minver: "1"
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.
8.2.3.3.2.1. SilentTrackNumber Element
name: "SilentTrackNumber"
path: "0*(\Segment\Cluster\SilentTracks\SilentTrackNumber)"
id: "0x58D7"
type: "uinteger"
minver: "1"
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.
8.2.3.3.3. Position Element
name: "Position"
path: "0*1(\Segment\Cluster\Position)"
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id: "0xA7"
maxOccurs: "1"
type: "uinteger"
minver: "1"
documentation: The Segment Position of the Cluster in the Segment (0
in live broadcast streams). It might help to resynchronise offset on
damaged streams.
8.2.3.3.4. PrevSize Element
name: "PrevSize"
path: "0*1(\Segment\Cluster\PrevSize)"
id: "0xAB"
maxOccurs: "1"
type: "uinteger"
minver: "1"
documentation: Size of the previous Cluster, in octets. Can be
useful for backward playing.
8.2.3.3.5. SimpleBlock Element
name: "SimpleBlock"
path: "0*(\Segment\Cluster\SimpleBlock)"
id: "0xA3"
type: "binary"
minver: "2"
documentation: Similar to Block but without all the extra
information, mostly used to reduced overhead when no extra feature is
needed. (see SimpleBlock Structure)
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8.2.3.3.6. BlockGroup Element
name: "BlockGroup"
path: "0*(\Segment\Cluster\BlockGroup)"
id: "0xA0"
type: "master"
minver: "1"
documentation: Basic container of information containing a single
Block and information specific to that Block.
8.2.3.3.6.1. Block Element
name: "Block"
path: "1*1(\Segment\Cluster\BlockGroup\Block)"
id: "0xA1"
minOccurs: "1"
maxOccurs: "1"
type: "binary"
minver: "1"
documentation: Block containing the actual data to be rendered and a
timestamp relative to the Cluster Timestamp. (see Block Structure)
8.2.3.3.6.2. BlockVirtual Element
name: "BlockVirtual"
path: "0*1(\Segment\Cluster\BlockGroup\BlockVirtual)"
id: "0xA2"
maxOccurs: "1"
type: "binary"
minver: "0"
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maxver: "0"
documentation: A Block with no data. It MUST be stored in the stream
at the place the real Block would be in display order. (see Block
Virtual)
8.2.3.3.6.3. BlockAdditions Element
name: "BlockAdditions"
path: "0*1(\Segment\Cluster\BlockGroup\BlockAdditions)"
id: "0x75A1"
maxOccurs: "1"
type: "master"
minver: "1"
documentation: 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.
####### BlockMore Element
name: "BlockMore"
path: "1*(\Segment\Cluster\BlockGroup\BlockAdditions\BlockMore)"
id: "0xA6"
minOccurs: "1"
type: "master"
minver: "1"
documentation: Contain the BlockAdditional and some parameters.
######## BlockAddID Element
name: "BlockAddID"
path: "1*1(\Segment\Cluster\BlockGroup\BlockAdditions\BlockMore\Block
AddID)"
id: "0xEE"
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minOccurs: "1"
maxOccurs: "1"
range: "not 0"
default: "1"
type: "uinteger"
minver: "1"
documentation: An ID to identify the BlockAdditional level.
######## BlockAdditional Element
name: "BlockAdditional"
path: "1*1(\Segment\Cluster\BlockGroup\BlockAdditions\BlockMore\Block
Additional)"
id: "0xA5"
minOccurs: "1"
maxOccurs: "1"
type: "binary"
minver: "1"
documentation: Interpreted by the codec as it wishes (using the
BlockAddID).
8.2.3.3.6.4. BlockDuration Element
name: "BlockDuration"
path: "0*1(\Segment\Cluster\BlockGroup\BlockDuration)"
id: "0x9B"
maxOccurs: "1"
default: "DefaultDuration"
type: "uinteger"
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minver: "1"
documentation: The duration of the Block (based on TimestampScale).
This Element is mandatory when DefaultDuration is set for the track
(but can be omitted as other default values). When not written and
with no DefaultDuration, the value is assumed to be the difference
between the timestamp of this Block and the timestamp of the next
Block in "display" order (not coding order). This Element can be
useful at the end of a Track (as there is not other Block available),
or when there is a break in a track like for subtitle tracks.
8.2.3.3.6.5. ReferencePriority Element
name: "ReferencePriority"
path: "1*1(\Segment\Cluster\BlockGroup\ReferencePriority)"
id: "0xFA"
minOccurs: "1"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "1"
documentation: 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.
8.2.3.3.6.6. ReferenceBlock Element
name: "ReferenceBlock"
path: "0*(\Segment\Cluster\BlockGroup\ReferenceBlock)"
id: "0xFB"
type: "integer"
minver: "1"
documentation: Timestamp of another frame used as a reference (ie: B
or P frame). The timestamp is relative to the block it's attached
to.
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8.2.3.3.6.7. ReferenceVirtual Element
name: "ReferenceVirtual"
path: "0*1(\Segment\Cluster\BlockGroup\ReferenceVirtual)"
id: "0xFD"
maxOccurs: "1"
type: "integer"
minver: "0"
maxver: "0"
documentation: The Segment Position of the data that would otherwise
be in position of the virtual block.
8.2.3.3.6.8. CodecState Element
name: "CodecState"
path: "0*1(\Segment\Cluster\BlockGroup\CodecState)"
id: "0xA4"
maxOccurs: "1"
type: "binary"
minver: "2"
documentation: The new codec state to use. Data interpretation is
private to the codec. This information SHOULD always be referenced
by a seek entry.
8.2.3.3.6.9. DiscardPadding Element
name: "DiscardPadding"
path: "0*1(\Segment\Cluster\BlockGroup\DiscardPadding)"
id: "0x75A2"
maxOccurs: "1"
type: "integer"
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minver: "4"
documentation: Duration in nanoseconds of the silent data added to
the Block (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.
8.2.3.3.6.10. Slices Element
name: "Slices"
path: "0*1(\Segment\Cluster\BlockGroup\Slices)"
id: "0x8E"
maxOccurs: "1"
type: "master"
minver: "1"
documentation: Contains slices description.
####### TimeSlice Element
name: "TimeSlice"
path: "0*(\Segment\Cluster\BlockGroup\Slices\TimeSlice)"
id: "0xE8"
type: "master"
minver: "1"
maxver: "1"
documentation: Contains extra time information about the data
contained in the Block. Being able to interpret this Element is not
REQUIRED for playback.
######## LaceNumber Element
name: "LaceNumber"
path: "0*1(\Segment\Cluster\BlockGroup\Slices\TimeSlice\LaceNumber)"
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id: "0xCC"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "1"
maxver: "1"
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.
######## FrameNumber Element
name: "FrameNumber"
path: "0*1(\Segment\Cluster\BlockGroup\Slices\TimeSlice\FrameNumber)"
id: "0xCD"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "0"
maxver: "0"
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).
######## BlockAdditionID Element
name: "BlockAdditionID"
path:
"0*1(\Segment\Cluster\BlockGroup\Slices\TimeSlice\BlockAdditionID)"
id: "0xCB"
maxOccurs: "1"
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default: "0"
type: "uinteger"
minver: "0"
maxver: "0"
documentation: The ID of the BlockAdditional Element (0 is the main
Block).
######## Delay Element
name: "Delay"
path: "0*1(\Segment\Cluster\BlockGroup\Slices\TimeSlice\Delay)"
id: "0xCE"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "0"
maxver: "0"
documentation: The (scaled) delay to apply to the Element.
######## SliceDuration Element
name: "SliceDuration"
path:
"0*1(\Segment\Cluster\BlockGroup\Slices\TimeSlice\SliceDuration)"
id: "0xCF"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "0"
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maxver: "0"
documentation: The (scaled) duration to apply to the Element.
8.2.3.3.6.11. ReferenceFrame Element
name: "ReferenceFrame"
path: "0*1(\Segment\Cluster\BlockGroup\ReferenceFrame)"
id: "0xC8"
maxOccurs: "1"
type: "master"
minver: "0"
maxver: "0"
documentation: DivX trick track extensions
####### ReferenceOffset Element
name: "ReferenceOffset"
path:
"1*1(\Segment\Cluster\BlockGroup\ReferenceFrame\ReferenceOffset)"
id: "0xC9"
minOccurs: "1"
maxOccurs: "1"
type: "uinteger"
minver: "0"
maxver: "0"
documentation: DivX trick track extensions
####### ReferenceTimestamp Element
name: "ReferenceTimestamp"
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path:
"1*1(\Segment\Cluster\BlockGroup\ReferenceFrame\ReferenceTimestamp)"
id: "0xCA"
minOccurs: "1"
maxOccurs: "1"
type: "uinteger"
minver: "0"
maxver: "0"
documentation: DivX trick track extensions
8.2.3.3.7. EncryptedBlock Element
name: "EncryptedBlock"
path: "0*(\Segment\Cluster\EncryptedBlock)"
id: "0xAF"
type: "binary"
minver: "0"
maxver: "0"
documentation: Similar to SimpleBlock but the data inside the Block
are Transformed (encrypt and/or signed). (see EncryptedBlock
Structure)
8.2.3.4. Tracks Element
name: "Tracks"
path: "0*(\Segment\Tracks)"
id: "0x1654AE6B"
type: "master"
minver: "1"
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documentation: A Top-Level Element of information with many tracks
described.
8.2.3.4.1. TrackEntry Element
name: "TrackEntry"
path: "1*(\Segment\Tracks\TrackEntry)"
id: "0xAE"
minOccurs: "1"
type: "master"
minver: "1"
documentation: Describes a track with all Elements.
8.2.3.4.1.1. TrackNumber Element
name: "TrackNumber"
path: "1*1(\Segment\Tracks\TrackEntry\TrackNumber)"
id: "0xD7"
minOccurs: "1"
maxOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "1"
documentation: The track number as used in the Block Header (using
more than 127 tracks is not encouraged, though the design allows an
unlimited number).
8.2.3.4.1.2. TrackUID Element
name: "TrackUID"
path: "1*1(\Segment\Tracks\TrackEntry\TrackUID)"
id: "0x73C5"
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minOccurs: "1"
maxOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "1"
documentation: A unique ID to identify the Track. This SHOULD be
kept the same when making a direct stream copy of the Track to
another file.
8.2.3.4.1.3. TrackType Element
name: "TrackType"
path: "1*1(\Segment\Tracks\TrackEntry\TrackType)"
id: "0x83"
minOccurs: "1"
maxOccurs: "1"
range: "1-254"
type: "uinteger"
minver: "1"
documentation: A set of track types coded on 8 bits.
8.2.3.4.1.4. FlagEnabled Element
name: "FlagEnabled"
path: "1*1(\Segment\Tracks\TrackEntry\FlagEnabled)"
id: "0xB9"
minOccurs: "1"
maxOccurs: "1"
range: "0-1"
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default: "1"
type: "uinteger"
minver: "2"
documentation: Set if the track is usable. (1 bit)
8.2.3.4.1.5. FlagDefault Element
name: "FlagDefault"
path: "1*1(\Segment\Tracks\TrackEntry\FlagDefault)"
id: "0x88"
minOccurs: "1"
maxOccurs: "1"
range: "0-1"
default: "1"
type: "uinteger"
minver: "1"
documentation: Set if that track (audio, video or subs) SHOULD be
active if no language found matches the user preference. (1 bit)
8.2.3.4.1.6. FlagForced Element
name: "FlagForced"
path: "1*1(\Segment\Tracks\TrackEntry\FlagForced)"
id: "0x55AA"
minOccurs: "1"
maxOccurs: "1"
range: "0-1"
default: "0"
type: "uinteger"
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minver: "1"
documentation: Set if that track MUST be active during playback.
There can be many forced track for a kind (audio, video or subs), the
player SHOULD select the one which language matches the user
preference or the default + forced track. Overlay MAY happen between
a forced and non-forced track of the same kind. (1 bit)
8.2.3.4.1.7. FlagLacing Element
name: "FlagLacing"
path: "1*1(\Segment\Tracks\TrackEntry\FlagLacing)"
id: "0x9C"
minOccurs: "1"
maxOccurs: "1"
range: "0-1"
default: "1"
type: "uinteger"
minver: "1"
documentation: Set if the track MAY contain blocks using lacing. (1
bit)
8.2.3.4.1.8. MinCache Element
name: "MinCache"
path: "1*1(\Segment\Tracks\TrackEntry\MinCache)"
id: "0x6DE7"
minOccurs: "1"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "1"
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documentation: The minimum number of frames a player SHOULD be able
to cache during playback. If set to 0, the reference pseudo-cache
system is not used.
8.2.3.4.1.9. MaxCache Element
name: "MaxCache"
path: "0*1(\Segment\Tracks\TrackEntry\MaxCache)"
id: "0x6DF8"
maxOccurs: "1"
type: "uinteger"
minver: "1"
documentation: The maximum cache size necessary to store referenced
frames in and the current frame. 0 means no cache is needed.
8.2.3.4.1.10. DefaultDuration Element
name: "DefaultDuration"
path: "0*1(\Segment\Tracks\TrackEntry\DefaultDuration)"
id: "0x23E383"
maxOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "1"
documentation: Number of nanoseconds (not scaled via TimestampScale)
per frame ('frame' in the Matroska sense -- one Element put into a
(Simple)Block).
8.2.3.4.1.11. DefaultDecodedFieldDuration Element
name: "DefaultDecodedFieldDuration"
path: "0*1(\Segment\Tracks\TrackEntry\DefaultDecodedFieldDuration)"
id: "0x234E7A"
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maxOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "4"
documentation: The period in nanoseconds (not scaled by
TimestampScale) between two successive fields at the output of the
decoding process (see the notes)
8.2.3.4.1.12. TrackTimestampScale Element
name: "TrackTimestampScale"
path: "1*1(\Segment\Tracks\TrackEntry\TrackTimestampScale)"
id: "0x23314F"
minOccurs: "1"
maxOccurs: "1"
range: "> 0x0p+0"
default: "0x1p+0"
type: "float"
minver: "1"
maxver: "3"
documentation: 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).
8.2.3.4.1.13. TrackOffset Element
name: "TrackOffset"
path: "0*1(\Segment\Tracks\TrackEntry\TrackOffset)"
id: "0x537F"
maxOccurs: "1"
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default: "0"
type: "integer"
minver: "0"
maxver: "0"
documentation: A value to add to the Block's Timestamp. This can be
used to adjust the playback offset of a track.
8.2.3.4.1.14. MaxBlockAdditionID Element
name: "MaxBlockAdditionID"
path: "1*1(\Segment\Tracks\TrackEntry\MaxBlockAdditionID)"
id: "0x55EE"
minOccurs: "1"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "1"
documentation: The maximum value of BlockAddID. A value 0 means
there is no BlockAdditions for this track.
8.2.3.4.1.15. Name Element
name: "Name"
path: "0*1(\Segment\Tracks\TrackEntry\Name)"
id: "0x536E"
maxOccurs: "1"
type: "utf-8"
minver: "1"
documentation: A human-readable track name.
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8.2.3.4.1.16. Language Element
name: "Language"
path: "0*1(\Segment\Tracks\TrackEntry\Language)"
id: "0x22B59C"
maxOccurs: "1"
default: "eng"
type: "string"
minver: "1"
documentation: Specifies the language of the track in the Matroska
languages form. This Element MUST be ignored if the LanguageIETF
Element is used in the same TrackEntry.
8.2.3.4.1.17. LanguageIETF Element
name: "LanguageIETF"
path: "0*1(\Segment\Tracks\TrackEntry\LanguageIETF)"
id: "0x22B59D"
maxOccurs: "1"
type: "string"
minver: "4"
documentation: Specifies the language of the track according to BCP
47 and using the IANA Language Subtag Registry. If this Element is
used, then any Language Elements used in the same TrackEntry MUST be
ignored.
8.2.3.4.1.18. CodecID Element
name: "CodecID"
path: "1*1(\Segment\Tracks\TrackEntry\CodecID)"
id: "0x86"
minOccurs: "1"
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maxOccurs: "1"
type: "string"
minver: "1"
documentation: An ID corresponding to the codec, see the codec page
for more info.
8.2.3.4.1.19. CodecPrivate Element
name: "CodecPrivate"
path: "0*1(\Segment\Tracks\TrackEntry\CodecPrivate)"
id: "0x63A2"
maxOccurs: "1"
type: "binary"
minver: "1"
documentation: Private data only known to the codec.
8.2.3.4.1.20. CodecName Element
name: "CodecName"
path: "0*1(\Segment\Tracks\TrackEntry\CodecName)"
id: "0x258688"
maxOccurs: "1"
type: "utf-8"
minver: "1"
documentation: A human-readable string specifying the codec.
8.2.3.4.1.21. AttachmentLink Element
name: "AttachmentLink"
path: "0*1(\Segment\Tracks\TrackEntry\AttachmentLink)"
id: "0x7446"
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maxOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "1"
maxver: "3"
documentation: The UID of an attachment that is used by this codec.
8.2.3.4.1.22. CodecSettings Element
name: "CodecSettings"
path: "0*1(\Segment\Tracks\TrackEntry\CodecSettings)"
id: "0x3A9697"
maxOccurs: "1"
type: "utf-8"
minver: "0"
maxver: "0"
documentation: A string describing the encoding setting used.
8.2.3.4.1.23. CodecInfoURL Element
name: "CodecInfoURL"
path: "0*(\Segment\Tracks\TrackEntry\CodecInfoURL)"
id: "0x3B4040"
type: "string"
minver: "0"
maxver: "0"
documentation: A URL to find information about the codec used.
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8.2.3.4.1.24. CodecDownloadURL Element
name: "CodecDownloadURL"
path: "0*(\Segment\Tracks\TrackEntry\CodecDownloadURL)"
id: "0x26B240"
type: "string"
minver: "0"
maxver: "0"
documentation: A URL to download about the codec used.
8.2.3.4.1.25. CodecDecodeAll Element
name: "CodecDecodeAll"
path: "1*1(\Segment\Tracks\TrackEntry\CodecDecodeAll)"
id: "0xAA"
minOccurs: "1"
maxOccurs: "1"
range: "0-1"
default: "1"
type: "uinteger"
minver: "2"
documentation: The codec can decode potentially damaged data (1 bit).
8.2.3.4.1.26. TrackOverlay Element
name: "TrackOverlay"
path: "0*(\Segment\Tracks\TrackEntry\TrackOverlay)"
id: "0x6FAB"
type: "uinteger"
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minver: "1"
documentation: 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 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.
8.2.3.4.1.27. CodecDelay Element
name: "CodecDelay"
path: "0*1(\Segment\Tracks\TrackEntry\CodecDelay)"
id: "0x56AA"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "4"
documentation: CodecDelay is The codec-built-in delay in nanoseconds.
This value MUST be subtracted from each block timestamp in order to
get the actual timestamp. The value SHOULD be small so the muxing of
tracks with the same actual timestamp are in the same Cluster.
8.2.3.4.1.28. SeekPreRoll Element
name: "SeekPreRoll"
path: "1*1(\Segment\Tracks\TrackEntry\SeekPreRoll)"
id: "0x56BB"
minOccurs: "1"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "4"
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documentation: After a discontinuity, SeekPreRoll is the duration in
nanoseconds of the data the decoder MUST decode before the decoded
data is valid.
8.2.3.4.1.29. TrackTranslate Element
name: "TrackTranslate"
path: "0*(\Segment\Tracks\TrackEntry\TrackTranslate)"
id: "0x6624"
type: "master"
minver: "1"
documentation: The track identification for the given Chapter Codec.
####### TrackTranslateEditionUID Element
name: "TrackTranslateEditionUID"
path: "0*(\Segment\Tracks\TrackEntry\TrackTranslate\TrackTranslateEdi
tionUID)"
id: "0x66FC"
type: "uinteger"
minver: "1"
documentation: Specify an edition UID on which this translation
applies. When not specified, it means for all editions found in the
Segment.
####### TrackTranslateCodec Element
name: "TrackTranslateCodec"
path:
"1*1(\Segment\Tracks\TrackEntry\TrackTranslate\TrackTranslateCodec)"
id: "0x66BF"
minOccurs: "1"
maxOccurs: "1"
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type: "uinteger"
minver: "1"
documentation: The chapter codec.
####### TrackTranslateTrackID Element
name: "TrackTranslateTrackID"
path: "1*1(\Segment\Tracks\TrackEntry\TrackTranslate\TrackTranslateTr
ackID)"
id: "0x66A5"
minOccurs: "1"
maxOccurs: "1"
type: "binary"
minver: "1"
documentation: The binary value used to represent this track in the
chapter codec data. The format depends on the ChapProcessCodecID
used.
8.2.3.4.1.30. Video Element
name: "Video"
path: "0*1(\Segment\Tracks\TrackEntry\Video)"
id: "0xE0"
maxOccurs: "1"
type: "master"
minver: "1"
documentation: Video settings.
####### FlagInterlaced Element
name: "FlagInterlaced"
path: "1*1(\Segment\Tracks\TrackEntry\Video\FlagInterlaced)"
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id: "0x9A"
minOccurs: "1"
maxOccurs: "1"
range: "0-2"
default: "0"
type: "uinteger"
minver: "2"
documentation: A flag to declare if the video is known to be
progressive or interlaced and if applicable to declare details about
the interlacement.
####### FieldOrder Element
name: "FieldOrder"
path: "1*1(\Segment\Tracks\TrackEntry\Video\FieldOrder)"
id: "0x9D"
minOccurs: "1"
maxOccurs: "1"
range: "0-14"
default: "2"
type: "uinteger"
minver: "4"
documentation: Declare the field ordering of the video. If
FlagInterlaced is not set to 1, this Element MUST be ignored.
####### StereoMode Element
name: "StereoMode"
path: "0*1(\Segment\Tracks\TrackEntry\Video\StereoMode)"
id: "0x53B8"
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maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "3"
documentation: Stereo-3D video mode. There are some more details on
3D support in the Specification Notes.
####### AlphaMode Element
name: "AlphaMode"
path: "0*1(\Segment\Tracks\TrackEntry\Video\AlphaMode)"
id: "0x53C0"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "3"
documentation: Alpha Video Mode. Presence of this Element indicates
that the BlockAdditional Element could contain Alpha data.
####### OldStereoMode Element
name: "OldStereoMode"
path: "0*1(\Segment\Tracks\TrackEntry\Video\OldStereoMode)"
id: "0x53B9"
maxOccurs: "1"
type: "uinteger"
maxver: "0"
documentation: DEPRECATED, DO NOT USE. Bogus StereoMode value used
in old versions of libmatroska.
####### PixelWidth Element
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name: "PixelWidth"
path: "1*1(\Segment\Tracks\TrackEntry\Video\PixelWidth)"
id: "0xB0"
minOccurs: "1"
maxOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "1"
documentation: Width of the encoded video frames in pixels.
####### PixelHeight Element
name: "PixelHeight"
path: "1*1(\Segment\Tracks\TrackEntry\Video\PixelHeight)"
id: "0xBA"
minOccurs: "1"
maxOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "1"
documentation: Height of the encoded video frames in pixels.
####### PixelCropBottom Element
name: "PixelCropBottom"
path: "0*1(\Segment\Tracks\TrackEntry\Video\PixelCropBottom)"
id: "0x54AA"
maxOccurs: "1"
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default: "0"
type: "uinteger"
minver: "1"
documentation: The number of video pixels to remove at the bottom of
the image.
####### PixelCropTop Element
name: "PixelCropTop"
path: "0*1(\Segment\Tracks\TrackEntry\Video\PixelCropTop)"
id: "0x54BB"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "1"
documentation: The number of video pixels to remove at the top of the
image.
####### PixelCropLeft Element
name: "PixelCropLeft"
path: "0*1(\Segment\Tracks\TrackEntry\Video\PixelCropLeft)"
id: "0x54CC"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "1"
documentation: The number of video pixels to remove on the left of
the image.
####### PixelCropRight Element
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name: "PixelCropRight"
path: "0*1(\Segment\Tracks\TrackEntry\Video\PixelCropRight)"
id: "0x54DD"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "1"
documentation: The number of video pixels to remove on the right of
the image.
####### DisplayWidth Element
name: "DisplayWidth"
path: "0*1(\Segment\Tracks\TrackEntry\Video\DisplayWidth)"
id: "0x54B0"
maxOccurs: "1"
range: "not 0"
default: "PixelWidth - PixelCropLeft - PixelCropRight"
type: "uinteger"
minver: "1"
documentation: Width of the video frames to display. Applies to the
video frame after cropping (PixelCrop* Elements). The default value
is only valid when DisplayUnit is 0.
####### DisplayHeight Element
name: "DisplayHeight"
path: "0*1(\Segment\Tracks\TrackEntry\Video\DisplayHeight)"
id: "0x54BA"
maxOccurs: "1"
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range: "not 0"
default: "PixelHeight - PixelCropTop - PixelCropBottom"
type: "uinteger"
minver: "1"
documentation: Height of the video frames to display. Applies to the
video frame after cropping (PixelCrop* Elements). The default value
is only valid when DisplayUnit is 0.
####### DisplayUnit Element
name: "DisplayUnit"
path: "0*1(\Segment\Tracks\TrackEntry\Video\DisplayUnit)"
id: "0x54B2"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "1"
documentation: How DisplayWidth & DisplayHeight are interpreted.
####### AspectRatioType Element
name: "AspectRatioType"
path: "0*1(\Segment\Tracks\TrackEntry\Video\AspectRatioType)"
id: "0x54B3"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "1"
documentation: Specify the possible modifications to the aspect
ratio.
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####### ColourSpace Element
name: "ColourSpace"
path: "0*1(\Segment\Tracks\TrackEntry\Video\ColourSpace)"
id: "0x2EB524"
maxOccurs: "1"
size: "4"
type: "binary"
minver: "1"
documentation: Specify the pixel format used for the Track's data as
a FourCC. This value is similar in scope to the biCompression value
of AVI's BITMAPINFOHEADER. This Element is MANDATORY in TrackEntry
when the CodecID Element of the TrackEntry is set to
"V_UNCOMPRESSED".
####### GammaValue Element
name: "GammaValue"
path: "0*1(\Segment\Tracks\TrackEntry\Video\GammaValue)"
id: "0x2FB523"
maxOccurs: "1"
range: "> 0x0p+0"
type: "float"
minver: "0"
maxver: "0"
documentation: Gamma Value.
####### FrameRate Element
name: "FrameRate"
path: "0*1(\Segment\Tracks\TrackEntry\Video\FrameRate)"
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id: "0x2383E3"
maxOccurs: "1"
range: "> 0x0p+0"
type: "float"
minver: "0"
maxver: "0"
documentation: Number of frames per second. Informational only.
####### Colour Element
name: "Colour"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour)"
id: "0x55B0"
maxOccurs: "1"
type: "master"
minver: "4"
documentation: Settings describing the colour format.
######## MatrixCoefficients Element
name: "MatrixCoefficients"
path:
"0*1(\Segment\Tracks\TrackEntry\Video\Colour\MatrixCoefficients)"
id: "0x55B1"
maxOccurs: "1"
default: "2"
type: "uinteger"
minver: "4"
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documentation: 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 23001-8:2013/DCOR1.
######## BitsPerChannel Element
name: "BitsPerChannel"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\BitsPerChannel)"
id: "0x55B2"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "4"
documentation: Number of decoded bits per channel. A value of 0
indicates that the BitsPerChannel is unspecified.
######## ChromaSubsamplingHorz Element
name: "ChromaSubsamplingHorz"
path:
"0*1(\Segment\Tracks\TrackEntry\Video\Colour\ChromaSubsamplingHorz)"
id: "0x55B3"
maxOccurs: "1"
type: "uinteger"
minver: "4"
documentation: 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.
######## ChromaSubsamplingVert Element
name: "ChromaSubsamplingVert"
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path:
"0*1(\Segment\Tracks\TrackEntry\Video\Colour\ChromaSubsamplingVert)"
id: "0x55B4"
maxOccurs: "1"
type: "uinteger"
minver: "4"
documentation: 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.
######## CbSubsamplingHorz Element
name: "CbSubsamplingHorz"
path:
"0*1(\Segment\Tracks\TrackEntry\Video\Colour\CbSubsamplingHorz)"
id: "0x55B5"
maxOccurs: "1"
type: "uinteger"
minver: "4"
documentation: 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.
######## CbSubsamplingVert Element
name: "CbSubsamplingVert"
path:
"0*1(\Segment\Tracks\TrackEntry\Video\Colour\CbSubsamplingVert)"
id: "0x55B6"
maxOccurs: "1"
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type: "uinteger"
minver: "4"
documentation: The amount of pixels to remove in the Cb channel for
every pixel not removed vertically. This is additive with
ChromaSubsamplingVert.
######## ChromaSitingHorz Element
name: "ChromaSitingHorz"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\ChromaSitingHorz)"
id: "0x55B7"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "4"
documentation: How chroma is subsampled horizontally.
######## ChromaSitingVert Element
name: "ChromaSitingVert"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\ChromaSitingVert)"
id: "0x55B8"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "4"
documentation: How chroma is subsampled vertically.
######## Range Element
name: "Range"
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path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\Range)"
id: "0x55B9"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "4"
documentation: Clipping of the color ranges.
######## TransferCharacteristics Element
name: "TransferCharacteristics"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\TransferCharacteri
stics)"
id: "0x55BA"
maxOccurs: "1"
default: "2"
type: "uinteger"
minver: "4"
documentation: The transfer characteristics of the video. For
clarity, the value and meanings for TransferCharacteristics 1-15 are
adopted from Table 3 of ISO/IEC 23001-8:2013/DCOR1.
TransferCharacteristics 16-18 are proposed values.
######## Primaries Element
name: "Primaries"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\Primaries)"
id: "0x55BB"
maxOccurs: "1"
default: "2"
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type: "uinteger"
minver: "4"
documentation: The colour primaries of the video. For clarity, the
value and meanings for Primaries are adopted from Table 2 of ISO/IEC
23001-8:2013/DCOR1.
######## MaxCLL Element
name: "MaxCLL"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\MaxCLL)"
id: "0x55BC"
maxOccurs: "1"
type: "uinteger"
minver: "4"
documentation: Maximum brightness of a single pixel (Maximum Content
Light Level) in candelas per square meter (cd/m^2).
######## MaxFALL Element
name: "MaxFALL"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\MaxFALL)"
id: "0x55BD"
maxOccurs: "1"
type: "uinteger"
minver: "4"
documentation: Maximum brightness of a single full frame (Maximum
Frame-Average Light Level) in candelas per square meter (cd/m^2).
######## MasteringMetadata Element
name: "MasteringMetadata"
path:
"0*1(\Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata)"
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id: "0x55D0"
maxOccurs: "1"
type: "master"
minver: "4"
documentation: SMPTE 2086 mastering data.
######### PrimaryRChromaticityX Element
name: "PrimaryRChromaticityX"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\
PrimaryRChromaticityX)"
id: "0x55D1"
maxOccurs: "1"
range: "0-1"
type: "float"
minver: "4"
documentation: Red X chromaticity coordinate as defined by CIE 1931.
######### PrimaryRChromaticityY Element
name: "PrimaryRChromaticityY"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\
PrimaryRChromaticityY)"
id: "0x55D2"
maxOccurs: "1"
range: "0-1"
type: "float"
minver: "4"
documentation: Red Y chromaticity coordinate as defined by CIE 1931.
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######### PrimaryGChromaticityX Element
name: "PrimaryGChromaticityX"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\
PrimaryGChromaticityX)"
id: "0x55D3"
maxOccurs: "1"
range: "0-1"
type: "float"
minver: "4"
documentation: Green X chromaticity coordinate as defined by CIE
1931.
######### PrimaryGChromaticityY Element
name: "PrimaryGChromaticityY"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\
PrimaryGChromaticityY)"
id: "0x55D4"
maxOccurs: "1"
range: "0-1"
type: "float"
minver: "4"
documentation: Green Y chromaticity coordinate as defined by CIE
1931.
######### PrimaryBChromaticityX Element
name: "PrimaryBChromaticityX"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\
PrimaryBChromaticityX)"
id: "0x55D5"
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maxOccurs: "1"
range: "0-1"
type: "float"
minver: "4"
documentation: Blue X chromaticity coordinate as defined by CIE 1931.
######### PrimaryBChromaticityY Element
name: "PrimaryBChromaticityY"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\
PrimaryBChromaticityY)"
id: "0x55D6"
maxOccurs: "1"
range: "0-1"
type: "float"
minver: "4"
documentation: Blue Y chromaticity coordinate as defined by CIE 1931.
######### WhitePointChromaticityX Element
name: "WhitePointChromaticityX"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\
WhitePointChromaticityX)"
id: "0x55D7"
maxOccurs: "1"
range: "0-1"
type: "float"
minver: "4"
documentation: White X chromaticity coordinate as defined by CIE
1931.
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######### WhitePointChromaticityY Element
name: "WhitePointChromaticityY"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\
WhitePointChromaticityY)"
id: "0x55D8"
maxOccurs: "1"
range: "0-1"
type: "float"
minver: "4"
documentation: White Y chromaticity coordinate as defined by CIE
1931.
######### LuminanceMax Element
name: "LuminanceMax"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\
LuminanceMax)"
id: "0x55D9"
maxOccurs: "1"
range: ">= 0x0p+0"
type: "float"
minver: "4"
documentation: Maximum luminance. Represented in candelas per square
meter (cd/m^2).
######### LuminanceMin Element
name: "LuminanceMin"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\
LuminanceMin)"
id: "0x55DA"
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maxOccurs: "1"
range: ">= 0x0p+0"
type: "float"
minver: "4"
documentation: Mininum luminance. Represented in candelas per square
meter (cd/m^2).
####### Projection Element
name: "Projection"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Projection)"
id: "0x7670"
maxOccurs: "1"
type: "master"
minver: "4"
documentation: Describes the video projection details. Used to
render spherical and VR videos.
######## ProjectionType Element
name: "ProjectionType"
path:
"1*1(\Segment\Tracks\TrackEntry\Video\Projection\ProjectionType)"
id: "0x7671"
minOccurs: "1"
maxOccurs: "1"
range: "0-3"
default: "0"
type: "uinteger"
minver: "4"
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documentation: Describes the projection used for this video track.
######## ProjectionPrivate Element
name: "ProjectionPrivate"
path:
"0*1(\Segment\Tracks\TrackEntry\Video\Projection\ProjectionPrivate)"
id: "0x7672"
maxOccurs: "1"
type: "binary"
minver: "4"
documentation: Private data that only applies to a specific
projection.SemanticsIf 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').Note: 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.
######## ProjectionPoseYaw Element
name: "ProjectionPoseYaw"
path:
"1*1(\Segment\Tracks\TrackEntry\Video\Projection\ProjectionPoseYaw)"
id: "0x7673"
minOccurs: "1"
maxOccurs: "1"
default: "0x0p+0"
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type: "float"
minver: "4"
documentation: Specifies a yaw rotation to the
projection.SemanticsValue 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 field should be in the -180 to 180 degree range.
######## ProjectionPosePitch Element
name: "ProjectionPosePitch"
path: "1*1(\Segment\Tracks\TrackEntry\Video\Projection\ProjectionPose
Pitch)"
id: "0x7674"
minOccurs: "1"
maxOccurs: "1"
default: "0x0p+0"
type: "float"
minver: "4"
documentation: Specifies a pitch rotation to the
projection.SemanticsValue 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 field should be in
the -90 to 90 degree range.
######## ProjectionPoseRoll Element
name: "ProjectionPoseRoll"
path:
"1*1(\Segment\Tracks\TrackEntry\Video\Projection\ProjectionPoseRoll)"
id: "0x7675"
minOccurs: "1"
maxOccurs: "1"
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default: "0x0p+0"
type: "float"
minver: "4"
documentation: Specifies a roll rotation to the
projection.SemanticsValue 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 field should be in the -180 to 180 degree range.
8.2.3.4.1.31. Audio Element
name: "Audio"
path: "0*1(\Segment\Tracks\TrackEntry\Audio)"
id: "0xE1"
maxOccurs: "1"
type: "master"
minver: "1"
documentation: Audio settings.
####### SamplingFrequency Element
name: "SamplingFrequency"
path: "1*1(\Segment\Tracks\TrackEntry\Audio\SamplingFrequency)"
id: "0xB5"
minOccurs: "1"
maxOccurs: "1"
range: "> 0x0p+0"
default: "0x1.f4p+12"
type: "float"
minver: "1"
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documentation: Sampling frequency in Hz.
####### OutputSamplingFrequency Element
name: "OutputSamplingFrequency"
path: "0*1(\Segment\Tracks\TrackEntry\Audio\OutputSamplingFrequency)"
id: "0x78B5"
maxOccurs: "1"
range: "> 0x0p+0"
default: "SamplingFrequency"
type: "float"
minver: "1"
documentation: Real output sampling frequency in Hz (used for SBR
techniques).
####### Channels Element
name: "Channels"
path: "1*1(\Segment\Tracks\TrackEntry\Audio\Channels)"
id: "0x9F"
minOccurs: "1"
maxOccurs: "1"
range: "not 0"
default: "1"
type: "uinteger"
minver: "1"
documentation: Numbers of channels in the track.
####### ChannelPositions Element
name: "ChannelPositions"
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path: "0*1(\Segment\Tracks\TrackEntry\Audio\ChannelPositions)"
id: "0x7D7B"
maxOccurs: "1"
type: "binary"
minver: "0"
maxver: "0"
documentation: Table of horizontal angles for each successive
channel, see appendix.
####### BitDepth Element
name: "BitDepth"
path: "0*1(\Segment\Tracks\TrackEntry\Audio\BitDepth)"
id: "0x6264"
maxOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "1"
documentation: Bits per sample, mostly used for PCM.
8.2.3.4.1.32. TrackOperation Element
name: "TrackOperation"
path: "0*1(\Segment\Tracks\TrackEntry\TrackOperation)"
id: "0xE2"
maxOccurs: "1"
type: "master"
minver: "3"
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documentation: Operation that needs to be applied on tracks to create
this virtual track. For more details look at the Specification Notes
on the subject.
####### TrackCombinePlanes Element
name: "TrackCombinePlanes"
path:
"0*1(\Segment\Tracks\TrackEntry\TrackOperation\TrackCombinePlanes)"
id: "0xE3"
maxOccurs: "1"
type: "master"
minver: "3"
documentation: Contains the list of all video plane tracks that need
to be combined to create this 3D track
######## TrackPlane Element
name: "TrackPlane"
path: "1*(\Segment\Tracks\TrackEntry\TrackOperation\TrackCombinePlane
s\TrackPlane)"
id: "0xE4"
minOccurs: "1"
type: "master"
minver: "3"
documentation: Contains a video plane track that need to be combined
to create this 3D track
######### TrackPlaneUID Element
name: "TrackPlaneUID"
path: "1*1(\Segment\Tracks\TrackEntry\TrackOperation\TrackCombinePlan
es\TrackPlane\TrackPlaneUID)"
id: "0xE5"
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minOccurs: "1"
maxOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "3"
documentation: The trackUID number of the track representing the
plane.
######### TrackPlaneType Element
name: "TrackPlaneType"
path: "1*1(\Segment\Tracks\TrackEntry\TrackOperation\TrackCombinePlan
es\TrackPlane\TrackPlaneType)"
id: "0xE6"
minOccurs: "1"
maxOccurs: "1"
type: "uinteger"
minver: "3"
documentation: The kind of plane this track corresponds to.
####### TrackJoinBlocks Element
name: "TrackJoinBlocks"
path:
"0*1(\Segment\Tracks\TrackEntry\TrackOperation\TrackJoinBlocks)"
id: "0xE9"
maxOccurs: "1"
type: "master"
minver: "3"
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documentation: Contains the list of all tracks whose Blocks need to
be combined to create this virtual track
######## TrackJoinUID Element
name: "TrackJoinUID"
path: "1*(\Segment\Tracks\TrackEntry\TrackOperation\TrackJoinBlocks\T
rackJoinUID)"
id: "0xED"
minOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "3"
documentation: The trackUID number of a track whose blocks are used
to create this virtual track.
8.2.3.4.1.33. TrickTrackUID Element
name: "TrickTrackUID"
path: "0*1(\Segment\Tracks\TrackEntry\TrickTrackUID)"
id: "0xC0"
maxOccurs: "1"
type: "uinteger"
minver: "0"
maxver: "0"
documentation: DivX trick track extensions
8.2.3.4.1.34. TrickTrackSegmentUID Element
name: "TrickTrackSegmentUID"
path: "0*1(\Segment\Tracks\TrackEntry\TrickTrackSegmentUID)"
id: "0xC1"
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maxOccurs: "1"
size: "16"
type: "binary"
minver: "0"
maxver: "0"
documentation: DivX trick track extensions
8.2.3.4.1.35. TrickTrackFlag Element
name: "TrickTrackFlag"
path: "0*1(\Segment\Tracks\TrackEntry\TrickTrackFlag)"
id: "0xC6"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "0"
maxver: "0"
documentation: DivX trick track extensions
8.2.3.4.1.36. TrickMasterTrackUID Element
name: "TrickMasterTrackUID"
path: "0*1(\Segment\Tracks\TrackEntry\TrickMasterTrackUID)"
id: "0xC7"
maxOccurs: "1"
type: "uinteger"
minver: "0"
maxver: "0"
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documentation: DivX trick track extensions
8.2.3.4.1.37. TrickMasterTrackSegmentUID Element
name: "TrickMasterTrackSegmentUID"
path: "0*1(\Segment\Tracks\TrackEntry\TrickMasterTrackSegmentUID)"
id: "0xC4"
maxOccurs: "1"
size: "16"
type: "binary"
minver: "0"
maxver: "0"
documentation: DivX trick track extensions
8.2.3.4.1.38. ContentEncodings Element
name: "ContentEncodings"
path: "0*1(\Segment\Tracks\TrackEntry\ContentEncodings)"
id: "0x6D80"
maxOccurs: "1"
type: "master"
minver: "1"
documentation: Settings for several content encoding mechanisms like
compression or encryption.
####### ContentEncoding Element
name: "ContentEncoding"
path:
"1*(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncoding)"
id: "0x6240"
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minOccurs: "1"
type: "master"
minver: "1"
documentation: Settings for one content encoding like compression or
encryption.
######## ContentEncodingOrder Element
name: "ContentEncodingOrder"
path: "1*1(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncodin
g\ContentEncodingOrder)"
id: "0x5031"
minOccurs: "1"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "1"
documentation: Tells when this modification was used during encoding/
muxing starting with 0 and counting upwards. The decoder/demuxer has
to start with the highest order number it finds and work its way
down. This value has to be unique over all ContentEncodingOrder
Elements in the Segment.
######## ContentEncodingScope Element
name: "ContentEncodingScope"
path: "1*1(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncodin
g\ContentEncodingScope)"
id: "0x5032"
minOccurs: "1"
maxOccurs: "1"
range: "not 0"
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default: "1"
type: "uinteger"
minver: "1"
documentation: A bit field that describes which Elements have been
modified in this way. Values (big endian) can be OR'ed. Possible
values: 1 - all frame contents, 2 - the track's private data, 4 - the
next ContentEncoding (next ContentEncodingOrder. Either the data
inside ContentCompression and/or ContentEncryption)
######## ContentEncodingType Element
name: "ContentEncodingType"
path: "1*1(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncodin
g\ContentEncodingType)"
id: "0x5033"
minOccurs: "1"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "1"
documentation: A value describing what kind of transformation has
been done. Possible values: 0 - compression, 1 - encryption
######## ContentCompression Element
name: "ContentCompression"
path: "0*1(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncodin
g\ContentCompression)"
id: "0x5034"
maxOccurs: "1"
type: "master"
minver: "1"
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documentation: 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.
######### ContentCompAlgo Element
name: "ContentCompAlgo"
path: "1*1(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncodin
g\ContentCompression\ContentCompAlgo)"
id: "0x4254"
minOccurs: "1"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "1"
documentation: The compression algorithm used. Algorithms that have
been specified so far are: 0 - zlib, 1 - bzlib, 2 - lzo1x 3 - Header
Stripping
######### ContentCompSettings Element
name: "ContentCompSettings"
path: "0*1(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncodin
g\ContentCompression\ContentCompSettings)"
id: "0x4255"
maxOccurs: "1"
type: "binary"
minver: "1"
documentation: Settings that might be needed by the decompressor.
For Header Stripping (ContentCompAlgo=3), the bytes that were removed
from the beggining of each frames of the track.
######## ContentEncryption Element
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name: "ContentEncryption"
path: "0*1(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncodin
g\ContentEncryption)"
id: "0x5035"
maxOccurs: "1"
type: "master"
minver: "1"
documentation: Settings describing the encryption used. This Element
MUST be present if the value of ContentEncodingType is 1 and absent
otherwise.
######### ContentEncAlgo Element
name: "ContentEncAlgo"
path: "0*1(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncodin
g\ContentEncryption\ContentEncAlgo)"
id: "0x47E1"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "1"
documentation: The encryption algorithm used. The value '0' means
that the contents have not been encrypted but only signed.
Predefined values: 1 - DES, 2 - 3DES, 3 - Twofish, 4 - Blowfish, 5 -
AES
######### ContentEncKeyID Element
name: "ContentEncKeyID"
path: "0*1(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncodin
g\ContentEncryption\ContentEncKeyID)"
id: "0x47E2"
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maxOccurs: "1"
type: "binary"
minver: "1"
documentation: For public key algorithms this is the ID of the public
key the the data was encrypted with.
######### ContentSignature Element
name: "ContentSignature"
path: "0*1(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncodin
g\ContentEncryption\ContentSignature)"
id: "0x47E3"
maxOccurs: "1"
type: "binary"
minver: "1"
documentation: A cryptographic signature of the contents.
######### ContentSigKeyID Element
name: "ContentSigKeyID"
path: "0*1(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncodin
g\ContentEncryption\ContentSigKeyID)"
id: "0x47E4"
maxOccurs: "1"
type: "binary"
minver: "1"
documentation: This is the ID of the private key the data was signed
with.
######### ContentSigAlgo Element
name: "ContentSigAlgo"
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path: "0*1(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncodin
g\ContentEncryption\ContentSigAlgo)"
id: "0x47E5"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "1"
documentation: The algorithm used for the signature. A value of '0'
means that the contents have not been signed but only encrypted.
Predefined values: 1 - RSA
######### ContentSigHashAlgo Element
name: "ContentSigHashAlgo"
path: "0*1(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncodin
g\ContentEncryption\ContentSigHashAlgo)"
id: "0x47E6"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "1"
documentation: The hash algorithm used for the signature. A value of
'0' means that the contents have not been signed but only encrypted.
Predefined values: 1 - SHA1-160 2 - MD5
8.2.3.5. Cues Element
name: "Cues"
path: "0*1(\Segment\Cues)"
id: "0x1C53BB6B"
maxOccurs: "1"
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type: "master"
minver: "1"
documentation: A Top-Level Element to speed seeking access. All
entries are local to the Segment. This Element SHOULD be mandatory
for non "live" streams.
8.2.3.5.1. CuePoint Element
name: "CuePoint"
path: "1*(\Segment\Cues\CuePoint)"
id: "0xBB"
minOccurs: "1"
type: "master"
minver: "1"
documentation: Contains all information relative to a seek point in
the Segment.
8.2.3.5.1.1. CueTime Element
name: "CueTime"
path: "1*1(\Segment\Cues\CuePoint\CueTime)"
id: "0xB3"
minOccurs: "1"
maxOccurs: "1"
type: "uinteger"
minver: "1"
documentation: Absolute timestamp according to the Segment time base.
8.2.3.5.1.2. CueTrackPositions Element
name: "CueTrackPositions"
path: "1*(\Segment\Cues\CuePoint\CueTrackPositions)"
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id: "0xB7"
minOccurs: "1"
type: "master"
minver: "1"
documentation: Contain positions for different tracks corresponding
to the timestamp.
####### CueTrack Element
name: "CueTrack"
path: "1*1(\Segment\Cues\CuePoint\CueTrackPositions\CueTrack)"
id: "0xF7"
minOccurs: "1"
maxOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "1"
documentation: The track for which a position is given.
####### CueClusterPosition Element
name: "CueClusterPosition"
path:
"1*1(\Segment\Cues\CuePoint\CueTrackPositions\CueClusterPosition)"
id: "0xF1"
minOccurs: "1"
maxOccurs: "1"
type: "uinteger"
minver: "1"
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documentation: The Segment Position of the Cluster containing the
associated Block.
####### CueRelativePosition Element
name: "CueRelativePosition"
path:
"0*1(\Segment\Cues\CuePoint\CueTrackPositions\CueRelativePosition)"
id: "0xF0"
maxOccurs: "1"
type: "uinteger"
minver: "4"
documentation: 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.
####### CueDuration Element
name: "CueDuration"
path: "0*1(\Segment\Cues\CuePoint\CueTrackPositions\CueDuration)"
id: "0xB2"
maxOccurs: "1"
type: "uinteger"
minver: "4"
documentation: The duration of the block according to the Segment
time base. If missing the track's DefaultDuration does not apply and
no duration information is available in terms of the cues.
####### CueBlockNumber Element
name: "CueBlockNumber"
path: "0*1(\Segment\Cues\CuePoint\CueTrackPositions\CueBlockNumber)"
id: "0x5378"
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maxOccurs: "1"
range: "not 0"
default: "1"
type: "uinteger"
minver: "1"
documentation: Number of the Block in the specified Cluster.
####### CueCodecState Element
name: "CueCodecState"
path: "0*1(\Segment\Cues\CuePoint\CueTrackPositions\CueCodecState)"
id: "0xEA"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "2"
documentation: The Segment Position of the Codec State corresponding
to this Cue Element. 0 means that the data is taken from the initial
Track Entry.
####### CueReference Element
name: "CueReference"
path: "0*(\Segment\Cues\CuePoint\CueTrackPositions\CueReference)"
id: "0xDB"
type: "master"
minver: "2"
documentation: The Clusters containing the referenced Blocks.
######## CueRefTime Element
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name: "CueRefTime"
path: "1*1(\Segment\Cues\CuePoint\CueTrackPositions\CueReference\CueR
efTime)"
id: "0x96"
minOccurs: "1"
maxOccurs: "1"
type: "uinteger"
minver: "2"
documentation: Timestamp of the referenced Block.
######## CueRefCluster Element
name: "CueRefCluster"
path: "1*1(\Segment\Cues\CuePoint\CueTrackPositions\CueReference\CueR
efCluster)"
id: "0x97"
minOccurs: "1"
maxOccurs: "1"
type: "uinteger"
minver: "0"
maxver: "0"
documentation: The Segment Position of the Cluster containing the
referenced Block.
######## CueRefNumber Element
name: "CueRefNumber"
path: "0*1(\Segment\Cues\CuePoint\CueTrackPositions\CueReference\CueR
efNumber)"
id: "0x535F"
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maxOccurs: "1"
range: "not 0"
default: "1"
type: "uinteger"
minver: "0"
maxver: "0"
documentation: Number of the referenced Block of Track X in the
specified Cluster.
######## CueRefCodecState Element
name: "CueRefCodecState"
path: "0*1(\Segment\Cues\CuePoint\CueTrackPositions\CueReference\CueR
efCodecState)"
id: "0xEB"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "0"
maxver: "0"
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.
8.2.3.6. Attachments Element
name: "Attachments"
path: "0*1(\Segment\Attachments)"
id: "0x1941A469"
maxOccurs: "1"
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type: "master"
minver: "1"
documentation: Contain attached files.
8.2.3.6.1. AttachedFile Element
name: "AttachedFile"
path: "1*(\Segment\Attachments\AttachedFile)"
id: "0x61A7"
minOccurs: "1"
type: "master"
minver: "1"
documentation: An attached file.
8.2.3.6.1.1. FileDescription Element
name: "FileDescription"
path: "0*1(\Segment\Attachments\AttachedFile\FileDescription)"
id: "0x467E"
maxOccurs: "1"
type: "utf-8"
minver: "1"
documentation: A human-friendly name for the attached file.
8.2.3.6.1.2. FileName Element
name: "FileName"
path: "1*1(\Segment\Attachments\AttachedFile\FileName)"
id: "0x466E"
minOccurs: "1"
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maxOccurs: "1"
type: "utf-8"
minver: "1"
documentation: Filename of the attached file.
8.2.3.6.1.3. FileMimeType Element
name: "FileMimeType"
path: "1*1(\Segment\Attachments\AttachedFile\FileMimeType)"
id: "0x4660"
minOccurs: "1"
maxOccurs: "1"
type: "string"
minver: "1"
documentation: MIME type of the file.
8.2.3.6.1.4. FileData Element
name: "FileData"
path: "1*1(\Segment\Attachments\AttachedFile\FileData)"
id: "0x465C"
minOccurs: "1"
maxOccurs: "1"
type: "binary"
minver: "1"
documentation: The data of the file.
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8.2.3.6.1.5. FileUID Element
name: "FileUID"
path: "1*1(\Segment\Attachments\AttachedFile\FileUID)"
id: "0x46AE"
minOccurs: "1"
maxOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "1"
documentation: Unique ID representing the file, as random as
possible.
8.2.3.6.1.6. FileReferral Element
name: "FileReferral"
path: "0*1(\Segment\Attachments\AttachedFile\FileReferral)"
id: "0x4675"
maxOccurs: "1"
type: "binary"
minver: "0"
maxver: "0"
documentation: A binary value that a track/codec can refer to when
the attachment is needed.
8.2.3.6.1.7. FileUsedStartTime Element
name: "FileUsedStartTime"
path: "0*1(\Segment\Attachments\AttachedFile\FileUsedStartTime)"
id: "0x4661"
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maxOccurs: "1"
type: "uinteger"
minver: "0"
maxver: "0"
documentation: DivX font extension
8.2.3.6.1.8. FileUsedEndTime Element
name: "FileUsedEndTime"
path: "0*1(\Segment\Attachments\AttachedFile\FileUsedEndTime)"
id: "0x4662"
maxOccurs: "1"
type: "uinteger"
minver: "0"
maxver: "0"
documentation: DivX font extension
8.2.3.7. Chapters Element
name: "Chapters"
path: "0*1(\Segment\Chapters)"
id: "0x1043A770"
maxOccurs: "1"
type: "master"
minver: "1"
documentation: A system to define basic menus and partition data.
For more detailed information, look at the Chapters Explanation.
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8.2.3.7.1. EditionEntry Element
name: "EditionEntry"
path: "1*(\Segment\Chapters\EditionEntry)"
id: "0x45B9"
minOccurs: "1"
type: "master"
minver: "1"
documentation: Contains all information about a Segment edition.
8.2.3.7.1.1. EditionUID Element
name: "EditionUID"
path: "0*1(\Segment\Chapters\EditionEntry\EditionUID)"
id: "0x45BC"
maxOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "1"
documentation: A unique ID to identify the edition. It's useful for
tagging an edition.
8.2.3.7.1.2. EditionFlagHidden Element
name: "EditionFlagHidden"
path: "1*1(\Segment\Chapters\EditionEntry\EditionFlagHidden)"
id: "0x45BD"
minOccurs: "1"
maxOccurs: "1"
range: "0-1"
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default: "0"
type: "uinteger"
minver: "1"
documentation: If an edition is hidden (1), it SHOULD NOT be
available to the user interface (but still to Control Tracks; see
flag notes). (1 bit)
8.2.3.7.1.3. EditionFlagDefault Element
name: "EditionFlagDefault"
path: "1*1(\Segment\Chapters\EditionEntry\EditionFlagDefault)"
id: "0x45DB"
minOccurs: "1"
maxOccurs: "1"
range: "0-1"
default: "0"
type: "uinteger"
minver: "1"
documentation: If a flag is set (1) the edition SHOULD be used as the
default one. (1 bit)
8.2.3.7.1.4. EditionFlagOrdered Element
name: "EditionFlagOrdered"
path: "0*1(\Segment\Chapters\EditionEntry\EditionFlagOrdered)"
id: "0x45DD"
maxOccurs: "1"
range: "0-1"
default: "0"
type: "uinteger"
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minver: "1"
documentation: Specify if the chapters can be defined multiple times
and the order to play them is enforced. (1 bit)
8.2.3.7.1.5. ChapterAtom Element
name: "ChapterAtom"
path: "1*(\Segment\Chapters\EditionEntry(1*(\ChapterAtom)))"
id: "0xB6"
minOccurs: "1"
type: "master"
recursive: "1"
minver: "1"
documentation: Contains the atom information to use as the chapter
atom (apply to all tracks).
####### ChapterUID Element
name: "ChapterUID"
path: "1*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterUID)"
id: "0x73C4"
minOccurs: "1"
maxOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "1"
documentation: A unique ID to identify the Chapter.
####### ChapterStringUID Element
name: "ChapterStringUID"
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path:
"0*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterStringUID)"
id: "0x5654"
maxOccurs: "1"
type: "utf-8"
minver: "3"
documentation: A unique string ID to identify the Chapter. Use for
WebVTT cue identifier storage.
####### ChapterTimeStart Element
name: "ChapterTimeStart"
path:
"1*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterTimeStart)"
id: "0x91"
minOccurs: "1"
maxOccurs: "1"
type: "uinteger"
minver: "1"
documentation: Timestamp of the start of Chapter (not scaled).
####### ChapterTimeEnd Element
name: "ChapterTimeEnd"
path:
"0*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterTimeEnd)"
id: "0x92"
maxOccurs: "1"
type: "uinteger"
minver: "1"
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documentation: Timestamp of the end of Chapter (timestamp excluded,
not scaled).
####### ChapterFlagHidden Element
name: "ChapterFlagHidden"
path:
"1*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterFlagHidden)"
id: "0x98"
minOccurs: "1"
maxOccurs: "1"
range: "0-1"
default: "0"
type: "uinteger"
minver: "1"
documentation: If a chapter is hidden (1), it SHOULD NOT be available
to the user interface (but still to Control Tracks; see flag notes).
(1 bit)
####### ChapterFlagEnabled Element
name: "ChapterFlagEnabled"
path:
"1*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterFlagEnabled)"
id: "0x4598"
minOccurs: "1"
maxOccurs: "1"
range: "0-1"
default: "1"
type: "uinteger"
minver: "1"
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documentation: Specify whether the chapter is enabled. It can be
enabled/disabled by a Control Track. When disabled, the movie SHOULD
skip all the content between the TimeStart and TimeEnd of this
chapter (see flag notes). (1 bit)
####### ChapterSegmentUID Element
name: "ChapterSegmentUID"
path:
"0*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterSegmentUID)"
id: "0x6E67"
maxOccurs: "1"
range: ">0"
size: "16"
type: "binary"
minver: "1"
documentation: The SegmentUID of another Segment to play during this
chapter.
usage notes: ChapterSegmentUID is mandatory if
ChapterSegmentEditionUID is used.
####### ChapterSegmentEditionUID Element
name: "ChapterSegmentEditionUID"
path: "0*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterSegmentE
ditionUID)"
id: "0x6EBC"
maxOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "1"
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documentation: The EditionUID to play from the Segment linked in
ChapterSegmentUID. If ChapterSegmentEditionUID is undeclared then no
Edition of the linked Segment is used.
####### ChapterPhysicalEquiv Element
name: "ChapterPhysicalEquiv"
path: "0*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterPhysical
Equiv)"
id: "0x63C3"
maxOccurs: "1"
type: "uinteger"
minver: "1"
documentation: Specify the physical equivalent of this ChapterAtom
like "DVD" (60) or "SIDE" (50), see complete list of values.
####### ChapterTrack Element
name: "ChapterTrack"
path: "0*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterTrack)"
id: "0x8F"
maxOccurs: "1"
type: "master"
minver: "1"
documentation: List of tracks on which the chapter applies. If this
Element is not present, all tracks apply
######## ChapterTrackNumber Element
name: "ChapterTrackNumber"
path: "1*(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterTrack\Cha
pterTrackNumber)"
id: "0x89"
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minOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "1"
documentation: UID of the Track to apply this chapter too. In the
absence of a control track, choosing this chapter will select the
listed Tracks and deselect unlisted tracks. Absence of this Element
indicates that the Chapter SHOULD be applied to any currently used
Tracks.
####### ChapterDisplay Element
name: "ChapterDisplay"
path: "0*(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterDisplay)"
id: "0x80"
type: "master"
minver: "1"
documentation: Contains all possible strings to use for the chapter
display.
######## ChapString Element
name: "ChapString"
path: "1*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterDisplay\
ChapString)"
id: "0x85"
minOccurs: "1"
maxOccurs: "1"
type: "utf-8"
minver: "1"
documentation: Contains the string to use as the chapter atom.
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######## ChapLanguage Element
name: "ChapLanguage"
path: "1*(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterDisplay\C
hapLanguage)"
id: "0x437C"
minOccurs: "1"
default: "eng"
type: "string"
minver: "1"
documentation: The languages corresponding to the string, in the
bibliographic ISO-639-2 form. This Element MUST be ignored if the
ChapLanguageIETF Element is used within the same ChapterDisplay
Element.
######## ChapLanguageIETF Element
name: "ChapLanguageIETF"
path: "0*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterDisplay\
ChapLanguageIETF)"
id: "0x437D"
maxOccurs: "1"
type: "string"
minver: "4"
documentation: Specifies the language used in the ChapString
according to BCP 47 and using the IANA Language Subtag Registry. If
this Element is used, then any ChapLanguage Elements used in the same
ChapterDisplay MUST be ignored.
######## ChapCountry Element
name: "ChapCountry"
path: "0*(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterDisplay\C
hapCountry)"
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id: "0x437E"
type: "string"
minver: "1"
documentation: The countries corresponding to the string, same 2
octets as in Internet domains. This Element MUST be ignored if the
ChapLanguageIETF Element is used within the same ChapterDisplay
Element.
####### ChapProcess Element
name: "ChapProcess"
path: "0*(\Segment\Chapters\EditionEntry\ChapterAtom\ChapProcess)"
id: "0x6944"
type: "master"
minver: "1"
documentation: Contains all the commands associated to the Atom.
######## ChapProcessCodecID Element
name: "ChapProcessCodecID"
path: "1*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapProcess\Cha
pProcessCodecID)"
id: "0x6955"
minOccurs: "1"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "1"
documentation: 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. More codec
IDs can be added later.
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######## ChapProcessPrivate Element
name: "ChapProcessPrivate"
path: "0*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapProcess\Cha
pProcessPrivate)"
id: "0x450D"
maxOccurs: "1"
type: "binary"
minver: "1"
documentation: Some optional data attached to the ChapProcessCodecID
information. For ChapProcessCodecID = 1, it is the "DVD level"
equivalent.
######## ChapProcessCommand Element
name: "ChapProcessCommand"
path: "0*(\Segment\Chapters\EditionEntry\ChapterAtom\ChapProcess\Chap
ProcessCommand)"
id: "0x6911"
type: "master"
minver: "1"
documentation: Contains all the commands associated to the Atom.
######### ChapProcessTime Element
name: "ChapProcessTime"
path: "1*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapProcess\Cha
pProcessCommand\ChapProcessTime)"
id: "0x6922"
minOccurs: "1"
maxOccurs: "1"
type: "uinteger"
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minver: "1"
documentation: Defines when the process command SHOULD be handled
######### ChapProcessData Element
name: "ChapProcessData"
path: "1*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapProcess\Cha
pProcessCommand\ChapProcessData)"
id: "0x6933"
minOccurs: "1"
maxOccurs: "1"
type: "binary"
minver: "1"
documentation: 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.
8.2.3.8. Tags Element
name: "Tags"
path: "0*(\Segment\Tags)"
id: "0x1254C367"
type: "master"
minver: "1"
documentation: Element containing metadata describing Tracks,
Editions, Chapters, Attachments, or the Segment as a whole. A list
of valid tags can be found here.
8.2.3.8.1. Tag Element
name: "Tag"
path: "1*(\Segment\Tags\Tag)"
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id: "0x7373"
minOccurs: "1"
type: "master"
minver: "1"
documentation: A single metadata descriptor.
8.2.3.8.1.1. Targets Element
name: "Targets"
path: "1*1(\Segment\Tags\Tag\Targets)"
id: "0x63C0"
minOccurs: "1"
maxOccurs: "1"
type: "master"
minver: "1"
documentation: 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.
####### TargetTypeValue Element
name: "TargetTypeValue"
path: "0*1(\Segment\Tags\Tag\Targets\TargetTypeValue)"
id: "0x68CA"
maxOccurs: "1"
default: "50"
type: "uinteger"
minver: "1"
documentation: A number to indicate the logical level of the target.
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####### TargetType Element
name: "TargetType"
path: "0*1(\Segment\Tags\Tag\Targets\TargetType)"
id: "0x63CA"
maxOccurs: "1"
type: "string"
minver: "1"
documentation: An informational string that can be used to display
the logical level of the target like "ALBUM", "TRACK", "MOVIE",
"CHAPTER", etc (see TargetType).
####### TagTrackUID Element
name: "TagTrackUID"
path: "0*(\Segment\Tags\Tag\Targets\TagTrackUID)"
id: "0x63C5"
default: "0"
type: "uinteger"
minver: "1"
documentation: A unique ID to identify the Track(s) the tags belong
to. If the value is 0 at this level, the tags apply to all tracks in
the Segment.
####### TagEditionUID Element
name: "TagEditionUID"
path: "0*(\Segment\Tags\Tag\Targets\TagEditionUID)"
id: "0x63C9"
default: "0"
type: "uinteger"
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minver: "1"
documentation: A unique ID to identify the EditionEntry(s) the tags
belong to. If the value is 0 at this level, the tags apply to all
editions in the Segment.
####### TagChapterUID Element
name: "TagChapterUID"
path: "0*(\Segment\Tags\Tag\Targets\TagChapterUID)"
id: "0x63C4"
default: "0"
type: "uinteger"
minver: "1"
documentation: A unique ID to identify the Chapter(s) the tags belong
to. If the value is 0 at this level, the tags apply to all chapters
in the Segment.
####### TagAttachmentUID Element
name: "TagAttachmentUID"
path: "0*(\Segment\Tags\Tag\Targets\TagAttachmentUID)"
id: "0x63C6"
default: "0"
type: "uinteger"
minver: "1"
documentation: A unique ID to identify the Attachment(s) the tags
belong to. If the value is 0 at this level, the tags apply to all
the attachments in the Segment.
8.2.3.8.1.2. SimpleTag Element
name: "SimpleTag"
path: "1*(\Segment\Tags\Tag(1*(\SimpleTag)))"
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id: "0x67C8"
minOccurs: "1"
type: "master"
recursive: "1"
minver: "1"
documentation: Contains general information about the target.
####### TagName Element
name: "TagName"
path: "1*1(\Segment\Tags\Tag\SimpleTag\TagName)"
id: "0x45A3"
minOccurs: "1"
maxOccurs: "1"
type: "utf-8"
minver: "1"
documentation: The name of the Tag that is going to be stored.
####### TagLanguage Element
name: "TagLanguage"
path: "1*1(\Segment\Tags\Tag\SimpleTag\TagLanguage)"
id: "0x447A"
minOccurs: "1"
maxOccurs: "1"
default: "und"
type: "string"
minver: "1"
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documentation: Specifies the language of the tag specified, in the
Matroska languages form. This Element MUST be ignored if the
TagLanguageIETF Element is used within the same SimpleTag Element.
####### TagLanguageIETF Element
name: "TagLanguageIETF"
path: "0*1(\Segment\Tags\Tag\SimpleTag\TagLanguageIETF)"
id: "0x447B"
maxOccurs: "1"
type: "string"
minver: "4"
documentation: Specifies the language used in the TagString according
to BCP 47 and using the IANA Language Subtag Registry. If this
Element is used, then any TagLanguage Elements used in the same
SimpleTag MUST be ignored.
####### TagDefault Element
name: "TagDefault"
path: "1*1(\Segment\Tags\Tag\SimpleTag\TagDefault)"
id: "0x4484"
minOccurs: "1"
maxOccurs: "1"
range: "0-1"
default: "1"
type: "uinteger"
minver: "1"
documentation: A boolean value to indicate if this is the default/
original language to use for the given tag.
####### TagString Element
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name: "TagString"
path: "0*1(\Segment\Tags\Tag\SimpleTag\TagString)"
id: "0x4487"
maxOccurs: "1"
type: "utf-8"
minver: "1"
documentation: The value of the Tag.
####### TagBinary Element
name: "TagBinary"
path: "0*1(\Segment\Tags\Tag\SimpleTag\TagBinary)"
id: "0x4485"
maxOccurs: "1"
type: "binary"
minver: "1"
documentation: 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
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"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".
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
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"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 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".
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.
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9.9. Optimum layout from a muxer
o SeekHead
o Info
o Tracks
o Chapters
o Attachments
o Tags
o Clusters
o Cues
9.10. Optimum layout after editing tags
o SeekHead
o Info
o Tracks
o Chapters
o Attachments
o Void
o Clusters
o Cues
o Tags
9.11. Optimum layout with Cues at the front
o SeekHead
o Info
o Tracks
o Chapters
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o Attachments
o Tags
o Cues
o Clusters
9.12. Cluster Timestamp
The "Timestamp Element" MUST occur as in storage order before any
"SimpleBlock", "BlockGroup", or "EncryptedBlock" within the "Cluster
Element".
10. Chapters
10.1. Edition and Chapter Flags
10.1.1. Chapter Flags
Two "Chapter Flags" are defined to describe the behavior of the
"ChapterAtom Element": "ChapterFlagHidden" and "ChapterFlagEnabled".
If a "ChapterAtom Element" is the "Child Element" of another
"ChapterAtom Element" with a "Chapter Flag" set to "true", then the
"Child ChapterAtom Element" MUST be interpreted as having its same
"Chapter Flag" set to "true". If a "ChapterAtom Element" is the
"Child Element" of another "ChapterAtom Element" with a "Chapter
Flag" set to "false" or if the "ChapterAtom Element" does not have a
"ChapterAtom Element" as its "Parent Element", then it MUST be
interpreted according to its own "Chapter Flag".
As an example, consider a "Parent ChapterAtom Element" that has its
"ChapterFlagHidden" set to "true" and also contains two child
"ChapterAtoms", the first with "ChapterFlagHidden" set to "true" and
the second with "ChapterFlagHidden" either set to "false" or not
present at all (in which case the default value of the Element
applies, which is "false"). Since the parent "ChapterAtom" has its
"ChapterFlagHidden" set to "true" then all of its children
"ChapterAtoms" MUST also be interpreted as if their
"ChapterFlagHidden" is also set to "true". However, if a "Control
Track" toggles the parent's "ChapterFlagHidden" flag to "false", then
only the parent "ChapterAtom" and its second child "ChapterAtom" MUST
be interpreted as if "ChapterFlagHidden" is set to "false". The
first child "ChapterAtom" which has the "ChapterFlagHidden" flag set
to "true" retains its value until its value is toggled to "false" by
a "Control Track".
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10.1.2. Edition Flags
Three "Edition Flags" are defined to describe the behavior of the
"EditionEntry Element": "EditionFlagHidden", "EditionFlagDefault" and
"EditionFlagOrdered".
10.1.2.1. EditionFlagHidden
The "EditionFlagHidden Flag" behaves similarly to the
"ChapterFlagHidden Flag": if "EditionFlagHidden" is set to "true",
its "Child ChapterAtoms Elements" MUST also be interpreted as if
their "ChapterFlagHidden" is also set to "true", regardless of their
own "ChapterFlagHidden Flags". If "EditionFlagHidden" is toggled by
a "Control Track" to "false", the "ChapterFlagHidden Flags" of the
"Child ChapterAtoms Elements" SHALL determine whether the
"ChapterAtom" is hidden or not.
10.1.2.2. EditionFlagDefault
It is RECOMMENDED that no more than one "Edition" have an
"EditionFlagDefault Flag" set to "true". The first "Edition" with
both the "EditionFlagDefault Flag" set to "true" and the
"EditionFlagHidden Flag" set to "false" is the "Default Edition".
When all "EditionFlagDefault Flags" are set to "false", then the
first "Edition" is the "Default Edition".
10.1.2.3. 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 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" is set to "false", "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
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"Simple Chapters", a "Matroska Player" MUST ignore certain "Chapter
Elements". All these elements are now informational only.
The following list shows the different usage of "Chapter Elements"
between an ordered and non-ordered "Edition".
Chapter elements / ordered Edition | False | True ChapterUID | X | X
ChapterStringUID | X | X ChapterTimeStart | X | X ChapterTimeEnd |
- | X ChapterFlagHidden | X | X ChapterFlagEnabled | X | X
ChapterSegmentUID | - | X ChapterSegmentEditionUID | - | X
ChapterPhysicalEquiv | X | X ChapterTrack | - | X ChapterDisplay |
X | X ChapProcess | - | X
Furthermore there are other EBML "Elements" which could be used if
the "EditionFlagOrdered Flag" is set to "true".
Other elements / ordered Edition | False | True Info/SegmentFamily |
- | X Info/ChapterTranslate | - | X Track/TrackTranslate | - | X
These other "Elements" belong to the Matroska DVD menu system and are
only used when the "ChapProcessCodecID Element" is set to 1.
10.1.2.3.1. Ordered-Edition and Matroska Segment-Linking
o Hard Linking: "Ordered-Chapters" supersedes the "Hard Linking".
o Soft Linking: In this complex system "Ordered Chapters" are
REQUIRED and a "Chapter CODEC" MUST interpret the "ChapProcess" of
all chapters.
o Medium Linking: "Ordered Chapters" are used in a normal way and
can be combined with the "ChapterSegmentUID" element which
establishes a link to another Matroska file/Segment.
See Section 23) for more information about "Hard Linking", "Soft
Linking" and "Medium Linking".
10.2. 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).
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10.2.1. Matroska Script (0)
This is the case when "ChapProcessCodecID" = 0. This is a script
language build for Matroska purposes. The inspiration comes from
ActionScript, javascript and other similar scripting languages. The
commands are stored as text commands, in UTF-8. The syntax is C
like, with commands spanned on many lines, each terminating with a
";". You can also include comments at the end of lines with "//" or
comment many lines using "/* */". The scripts are stored in
ChapProcessData. For the moment ChapProcessPrivate is not used.
The one and only command existing for the moment is "GotoAndPlay(
ChapterUID );". As the same suggests, it means that when this
command is encountered, the "Matroska Player" SHOULD jump to the
"Chapter" specified by the UID and play it.
10.2.2. DVD menu (1)
This is the case when "ChapProcessCodecID" = 1. Each level of a
chapter corresponds to a logical level in the DVD system that is
stored in the first octet of the ChapProcessPrivate. This DVD
hierarchy is as follows:
ChapProcessPrivate | DVD Name | Hierarchy | Commands Possible |
Comment 0x30 | SS | DVD domain | - | First Play, Video Manager, Video
Title 0x2A | LU | Language Unit | - | Contains only PGCs 0x28 | TT |
Title | - | Contains only PGCs 0x20 | PGC | Program Group Chain
(PGC) | * | 0x18 | PG | Program 1 / Program 2 / Program 3 | - |
0x10 | PTT | Part Of Title 1 / Part Of Title 2 | - | Equivalent to
the chapters on the sleeve. 0x08 | CN | Cell 1 / Cell 2 / Cell 3 /
Cell 4 / Cell 5 / Cell 6 | - |
You can also recover wether a Segment is a Video Manager (VMG), Video
Title Set (VTS) or Video Title Set Menu (VTSM) from the
ChapterTranslateID element found in the Segment Info. This field
uses 2 octets as follows:
1. Domain Type: 0 for VMG, the domain number for VTS and VTSM
2. Domain Value: 0 for VMG and VTSM, 1 for the VTS source.
For instance, the menu part from VTS_01_0.VOB would be coded [1,0]
and the content part from VTS_02_3.VOB would be [2,1]. The VMG is
always [0,0]
The following octets of ChapProcessPrivate are as follows:
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Octet 1 | DVD Name | Following Octets 0x30 | SS | Domain name code
(1: 0x00= First play, 0xC0= VMG, 0x40= VTSM, 0x80= VTS) + VTS(M)
number (2) 0x2A | LU | Language code (2) + Language extension (1)
0x28 | TT | global Title number (2) + corresponding TTN of the VTS
(1) 0x20 | PGC | PGC number (2) + Playback Type (1) + Disabled User
Operations (4) 0x18 | PG | Program number (2) 0x10 | PTT | PTT-
chapter number (1) 0x08 | CN | Cell number [VOB ID(2)][Cell
ID(1)][Angle Num(1)]
If the level specified in ChapProcessPrivate is a PGC (0x20), there
is an octet called the Playback Type, specifying the kind of PGC
defined:
o 0x00: entry only/basic PGC
o 0x82: Title+Entry Menu (only found in the Video Manager domain)
o 0x83: Root Menu (only found in the VTSM domain)
o 0x84: Subpicture Menu (only found in the VTSM domain)
o 0x85: Audio Menu (only found in the VTSM domain)
o 0x86: Angle Menu (only found in the VTSM domain)
o 0x87: Chapter Menu (only found in the VTSM domain)
The next 4 following octets correspond to the User Operation flags
[17] in the standard PGC. When a bit is set, the command SHOULD be
disabled.
ChapProcessData contains the pre/post/cell commands in binary format
as there are stored on a DVD. There is just an octet preceding these
data to specify the number of commands in the element. As follows:
[# of commands(1)][command 1 (8)][command 2 (8)][command 3 (8)].
More information on the DVD commands and format on DVD-replica [18],
where we got most of the info about it. You can also get information
on DVD from the DVDinfo project [19].
10.3. 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.
o 00000ms - 05000ms : Intro
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o 05000ms - 25000ms : Before the crime
o 25000ms - 27500ms : The crime
o 27500ms - 38000ms : The killer arrested
o 38000ms - 43000ms : Credits
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>
<ChapLanguage>eng</ChapLanguage>
</ChapterDisplay>
<ChapterFlagHidden>0</ChapterFlagHidden>
<ChapterFlagEnabled>1</ChapterFlagEnabled>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>2311527</ChapterUID>
<ChapterTimeStart>5000000000</ChapterTimeStart>
<ChapterTimeEnd>25000000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Before the crime</ChapString>
<ChapLanguage>eng</ChapLanguage>
</ChapterDisplay>
<ChapterDisplay>
<ChapString>Avant le crime</ChapString>
<ChapLanguage>fra</ChapLanguage>
</ChapterDisplay>
<ChapterFlagHidden>0</ChapterFlagHidden>
<ChapterFlagEnabled>1</ChapterFlagEnabled>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>3430008</ChapterUID>
<ChapterTimeStart>25000000000</ChapterTimeStart>
<ChapterTimeEnd>27500000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>The crime</ChapString>
<ChapLanguage>eng</ChapLanguage>
</ChapterDisplay>
<ChapterDisplay>
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<ChapString>Le crime</ChapString>
<ChapLanguage>fra</ChapLanguage>
</ChapterDisplay>
<ChapterFlagHidden>0</ChapterFlagHidden>
<ChapterFlagEnabled>1</ChapterFlagEnabled>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>4548489</ChapterUID>
<ChapterTimeStart>27500000000</ChapterTimeStart>
<ChapterTimeEnd>38000000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>After the crime</ChapString>
<ChapLanguage>eng</ChapLanguage>
</ChapterDisplay>
<ChapterDisplay>
<ChapString>Apres le crime</ChapString>
<ChapLanguage>fra</ChapLanguage>
</ChapterDisplay>
<ChapterFlagHidden>0</ChapterFlagHidden>
<ChapterFlagEnabled>1</ChapterFlagEnabled>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>5666960</ChapterUID>
<ChapterTimeStart>38000000000</ChapterTimeStart>
<ChapterTimeEnd>43000000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Credits</ChapString>
<ChapLanguage>eng</ChapLanguage>
</ChapterDisplay>
<ChapterDisplay>
<ChapString>Generique</ChapString>
<ChapLanguage>fra</ChapLanguage>
</ChapterDisplay>
<ChapterFlagHidden>0</ChapterFlagHidden>
<ChapterFlagEnabled>1</ChapterFlagEnabled>
</ChapterAtom>
<EditionFlagDefault>0</EditionFlagDefault>
<EditionFlagHidden>0</EditionFlagHidden>
</EditionEntry>
</Chapters>
10.4. Example 2 : nested chapters
In this example an (existing) album is split into different chapters,
and one of them contain another splitting.
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10.4.1. The Micronauts "Bleep To Bleep"
o 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)
o 12:30 - 19:38 : Bleeper_O+2
o 19:40 - 22:20 : Baby wants to bleep (pt.4)
o 22:22 - 25:18 : Bleep to bleep
o 25:20 - 33:35 : Baby wants to bleep (k)
o 33:37 - 44:28 : Bleeper
<Chapters>
<EditionEntry>
<EditionUID>1281690858003401414</EditionUID>
<ChapterAtom>
<ChapterUID>1</ChapterUID>
<ChapterTimeStart>0</ChapterTimeStart>
<ChapterTimeEnd>748000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Baby wants to Bleep/Rock</ChapString>
<ChapLanguage>eng</ChapLanguage>
</ChapterDisplay>
<ChapterAtom>
<ChapterUID>2</ChapterUID>
<ChapterTimeStart>0</ChapterTimeStart>
<ChapterTimeEnd>278000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Baby wants to bleep (pt.1)</ChapString>
<ChapLanguage>eng</ChapLanguage>
</ChapterDisplay>
<ChapterFlagHidden>0</ChapterFlagHidden>
<ChapterFlagEnabled>1</ChapterFlagEnabled>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>3</ChapterUID>
<ChapterTimeStart>278000000</ChapterTimeStart>
<ChapterTimeEnd>432000000</ChapterTimeEnd>
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<ChapterDisplay>
<ChapString>Baby wants to rock</ChapString>
<ChapLanguage>eng</ChapLanguage>
</ChapterDisplay>
<ChapterFlagHidden>0</ChapterFlagHidden>
<ChapterFlagEnabled>1</ChapterFlagEnabled>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>4</ChapterUID>
<ChapterTimeStart>432000000</ChapterTimeStart>
<ChapterTimeEnd>633000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Baby wants to bleep (pt.2)</ChapString>
<ChapLanguage>eng</ChapLanguage>
</ChapterDisplay>
<ChapterFlagHidden>0</ChapterFlagHidden>
<ChapterFlagEnabled>1</ChapterFlagEnabled>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>5</ChapterUID>
<ChapterTimeStart>633000000</ChapterTimeStart>
<ChapterTimeEnd>748000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Baby wants to bleep (pt.3)</ChapString>
<ChapLanguage>eng</ChapLanguage>
</ChapterDisplay>
<ChapterFlagHidden>0</ChapterFlagHidden>
<ChapterFlagEnabled>1</ChapterFlagEnabled>
</ChapterAtom>
<ChapterFlagHidden>0</ChapterFlagHidden>
<ChapterFlagEnabled>1</ChapterFlagEnabled>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>6</ChapterUID>
<ChapterTimeStart>750000000</ChapterTimeStart>
<ChapterTimeEnd>1178500000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Bleeper_O+2</ChapString>
<ChapLanguage>eng</ChapLanguage>
</ChapterDisplay>
<ChapterFlagHidden>0</ChapterFlagHidden>
<ChapterFlagEnabled>1</ChapterFlagEnabled>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>7</ChapterUID>
<ChapterTimeStart>1180500000</ChapterTimeStart>
<ChapterTimeEnd>1340000000</ChapterTimeEnd>
<ChapterDisplay>
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<ChapString>Baby wants to bleep (pt.4)</ChapString>
<ChapLanguage>eng</ChapLanguage>
</ChapterDisplay>
<ChapterFlagHidden>0</ChapterFlagHidden>
<ChapterFlagEnabled>1</ChapterFlagEnabled>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>8</ChapterUID>
<ChapterTimeStart>1342000000</ChapterTimeStart>
<ChapterTimeEnd>1518000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Bleep to bleep</ChapString>
<ChapLanguage>eng</ChapLanguage>
</ChapterDisplay>
<ChapterFlagHidden>0</ChapterFlagHidden>
<ChapterFlagEnabled>1</ChapterFlagEnabled>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>9</ChapterUID>
<ChapterTimeStart>1520000000</ChapterTimeStart>
<ChapterTimeEnd>2015000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Baby wants to bleep (k)</ChapString>
<ChapLanguage>eng</ChapLanguage>
</ChapterDisplay>
<ChapterFlagHidden>0</ChapterFlagHidden>
<ChapterFlagEnabled>1</ChapterFlagEnabled>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>10</ChapterUID>
<ChapterTimeStart>2017000000</ChapterTimeStart>
<ChapterTimeEnd>2668000000</ChapterTimeEnd>
<ChapterDisplay>
<ChapString>Bleeper</ChapString>
<ChapLanguage>eng</ChapLanguage>
</ChapterDisplay>
<ChapterFlagHidden>0</ChapterFlagHidden>
<ChapterFlagEnabled>1</ChapterFlagEnabled>
</ChapterAtom>
<EditionFlagDefault>0</EditionFlagDefault>
<EditionFlagHidden>0</EditionFlagHidden>
</EditionEntry>
</Chapters>
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11. 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".
"Matroska Readers" MUST NOT execute files stored as "Attachment
Elements".
11.1. 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.
FileName | Image Orientation | Pixel Length of Smallest Side
cover.jpg | Portrait or square | 600 small_cover.png | Portrait or
square | 120 cover_land.png | Landscape | 600 small_cover_land.jpg |
Landscape | 120
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12. 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.
12.1. Recommendations
The following recommendations are provided to optimize Matroska
performance.
o Unless Matroska is used as a live stream, it SHOULD contain a
"Cues Element".
o For each video track, each keyframe SHOULD be referenced by a
"CuePoint Element".
o 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.
o For each subtitle track present, each subtitle frame SHOULD be
referenced by a "CuePoint Element" with a "CueDuration Element".
o 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.
o 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.
o If a "CuePoint Element" references "Cluster Element" that includes
a "CodecState Element", then that "CuePoint Element" MUST use a
"CueCodecState Element".
o "CuePoint Elements" SHOULD be numerically sorted in storage order
by the value of the "CueTime Element".
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13. Matroska Streaming
In Matroska, there are two kinds of streaming: file access and
livestreaming.
13.1. 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.
13.2. 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.
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"
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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.
14. Menu Specifications
This document is a _draft of the Menu system_ that will be the
default one in "Matroska". As it will just be composed of a Control
Track, it will be seen as a "codec" and could be replaced later by
something else if needed.
A menu is like what you see on DVDs, when you have some screens to
select the audio format, subtitles or scene selection.
14.1. Requirements
What we'll try to have is a system that can do almost everything done
on a DVD, or more, or better, or drop the unused features if
necessary.
As the name suggests, a Control Track is a track that can control the
playback of the file and/or all the playback features. To make it as
simple as possible for "Matroska Players", the Control Track will
just give orders to the "Matroska Player" and get the actions
associated with the highlights/hotspots.
14.1.1. Highlights/Hotspots
A highlight is basically a rectangle/key associated with an action
UID. When that rectangle/key is activated, the "Matroska Player"
send the UID of the action to the Control Track handler (codec). The
fact that it can also be a key means that even for audio only files,
a keyboard shortcut or button panel could be used for menus. But in
that case, the hotspot will have to be associated with a name to
display.
This highlight is sent from the Control Track to the "Matroska
Player". Then the "Matroska Player" has to handle that highlight
until it's deactivated (see Section 14.1.2).
The highlight contains a UID of the action, a displayable name (UTF-
8), an associated key (list of keys to be defined, probably
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up/down/left/right/select), a screen position/range and an image to
display. The image will be displayed either when the user place the
mouse over the rectangle (or any other shape), or when an option of
the screen is selected (not activated). There could be a second
image used when the option is activated. And there could be a third
image that can serve as background. This way you could have a still
image (like in some DVDs) for the menu and behind that image blank
video (small bitrate).
When a highlight is activated by the user, the "Matroska Player" has
to send the UID of the action to the Control Track. Then the Control
Track codec will handle the action and possibly give new orders to
the "Matroska Player".
The format used for storing images SHOULD be extensible. For the
moment we'll use PNG and BMP, both with alpha channel.
14.1.2. Playback features
All the following features will be sent from the Control Track to the
"Matroska Player" :
o Jump to chapter (UID, prev, next, number)
o Disable all tracks of a kind (audio, video, subtitle)
o Enable track UID (the kind doesn't matter)
o Define/Disable a highlight
o Enable/Disable jumping
o Enable/Disable track selection of a kind
o Select Edition ID (see chapters)
o Pause playback
o Stop playback
o Enable/Disable a Chapter UID
o Hide/Unhide a Chapter UID
All the actions will be written in a normal Matroska track, with a
timestamp. A "Menu Frame" SHOULD be able to contain more that one
action/highlight for a given timestamp. (to be determined, EBML
format structure)
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14.1.3. Player requirements
Some "Matroska Players" might not support the control track. That
mean they will play the active/looped parts as part of the data. So
I suggest putting the active/looped parts of a movie at the end of a
movie. When a Menu-aware "Matroska Player" encounter the default
Control Track of a "Matroska" file, the first order SHOULD be to jump
at the start of the active/looped part of the movie.
14.2. Working Graph
Matroska Source file -> Control Track <-> Player.
-> other tracks -> rendered
15. 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.
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".
16. Default Values
The default value of an "Element" is assumed when not present in the
data stream. It is assumed only in the scope of its "Parent
Element". For example, the "Language Element" is in the scope of the
"Track Element". If the "Parent Element" is not present or assumed,
then the "Child Element" cannot be assumed.
17. 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".
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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:
o Blu-ray movie: 1000000000ns/(48/1.001) = 20854167ns
o PAL broadcast/DVD: 1000000000ns/(50/1.000) = 20000000ns
o N/ATSC broadcast: 1000000000ns/(60/1.001) = 16683333ns
o hard-telecined DVD: 1000000000ns/(60/1.001) = 16683333ns (60
encoded interlaced fields per second)
o soft-telecined DVD: 1000000000ns/(60/1.001) = 16683333ns (48
encoded interlaced fields per second, with "repeat_first_field =
1")
18. 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".
19. Image 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
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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.
20. 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".
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 Section 15.
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21. MIME Types
There is no IETF endorsed MIME type for Matroska files. These
definitions can be used:
o .mka : Matroska audio "audio/x-matroska"
o .mkv : Matroska video "video/x-matroska"
o .mk3d : Matroska 3D video "video/x-matroska-3d"
22. 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".
22.1. Segment Position Exception
"Elements" that are defined to store a "Segment Position" MAY define
reserved values to indicate a special meaning.
22.2. 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|
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.
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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".
23. Linked Segments
Matroska provides several methods to link two or many "Segment
Elements" together to create a "Linked Segment". A "Linked Segment"
is a set of multiple "Segments" related together into a single
presentation by using Hard Linking, Medium Linking, or Soft Linking.
All "Segments" within a "Linked Segment" MUST utilize the same track
numbers and timescale. All "Segments" within a "Linked Segment" MUST
be stored within the same directory. All "Segments" within a "Linked
Segment" MUST store a "SegmentUID".
23.1. Hard Linking
Hard Linking (also called splitting) is the process of creating a
"Linked Segment" by relating multiple "Segment Elements" using the
"PrevUID" and "NextUID Elements". Within a "Linked Segment", the
timestamps of each "Segment" MUST follow consecutively in linking
order. With Hard Linking, the chapters of any "Segment" within the
"Linked Segment" MUST only reference the current "Segment". With
Hard Linking, the "NextUID" and "PrevUID" MUST reference the
respective "SegmentUID" values of the next and previous "Segments".
The first "Segment" of a "Linked Segment" MUST have a "NextUID
Element" and MUST NOT have a "PrevUID Element". The last "Segment"
of a "Linked Segment" MUST have a "PrevUID Element" and MUST NOT have
a "NextUID Element". The middle "Segments" of a "Linked Segment"
MUST have both a "NextUID Element" and a "PrevUID Element".
As an example, four "Segments" can be Hard Linked as a "Linked
Segment" through cross-referencing each other with "SegmentUID",
"PrevUID", and "NextUID", as in this table.
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+--------+------------------+-------------------+-------------------+
| file | SegmentUID | PrevUID | NextUID |
| name | | | |
+--------+------------------+-------------------+-------------------+
| "start | "71000c23cd31099 | n/a | "a77b3598941cb803 |
| .mkv" | 853fbc94dd984a5d | | eac0fcdafe44fac9" |
| | d" | | |
| "middl | "a77b3598941cb80 | "71000c23cd310998 | "6c92285fa6d3e827 |
| e.mkv" | 3eac0fcdafe44fac | 53fbc94dd984a5dd" | b198d120ea3ac674" |
| | 9" | | |
| "end.m | "6c92285fa6d3e82 | "a77b3598941cb803 | n/a |
| kv" | 7b198d120ea3ac67 | eac0fcdafe44fac9" | |
| | 4" | | |
+--------+------------------+-------------------+-------------------+
23.2. Medium Linking
Medium Linking creates relationships between "Segments" using Ordered
Chapters and the "ChapterSegmentUID Element". A "Segment 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"
together.
23.3. Soft Linking
Soft Linking is used by codec chapters. They can reference another
"Segment" and jump to that "Segment". The way the "Segments" are
described are internal to the chapter codec and unknown to the
Matroska level. But there are "Elements" within the "Info Element"
(such as "ChapterTranslate") that can translate a value representing
a "Segment" in the chapter codec and to the current "SegmentUID".
All "Segments" that could be used in a "Linked Segment" in this way
SHOULD be marked as members of the same family via the "SegmentFamily
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Element", so that the "Matroska Player" can quickly switch from one
to the other.
24. Track Flags
24.1. Default flag
The "default track" flag is a hint for a "Matroska Player" and SHOULD
always be changeable by the user. If the user wants to see or hear a
track of a certain kind (audio, video, subtitles) and hasn't chosen a
specific track, the "Matroska Player" SHOULD use the first track of
that kind whose "default track" flag is set to "1". If no such track
is found then the first track of this kind SHOULD be chosen.
Only one track of a kind MAY have its "default track" flag set in a
segment. If a track entry does not contain the "default track" flag
element then its default value "1" is to be used.
24.2. Forced flag
The "forced" flag tells the "Matroska Player" that it MUST display/
play this track or another track of the same kind that also has its
"forced" flag set. When there are multiple "forced" tracks, the
"Matroska Player" SHOULD determine the track based upon the language
of the forced flag or use the default flag if no track matches the
use languages. Another track of the same kind without the "forced"
flag may be use simultaneously with the "forced" track (like DVD
subtitles for example).
24.3. 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.
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
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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.
24.4. 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.
24.5. 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 colours 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).
For separate tracks, Matroska needs to define exactly which track
does what. "TrackOperation" with "TrackCombinePlanes" do that. For
more details look at Section 24.3.
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 [20] were 0: mono, 1: right
eye, 2: left eye, 3: both eyes.
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25. 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.
25.1. Timestamp Types
o Absolute Timestamp = Block+Cluster
o Relative Timestamp = Block
o Scaled Timestamp = Block+Cluster
o Raw Timestamp = (Block+Cluster)*TimestampScale*TrackTimestampScale
25.2. Block Timestamps
The "Block Element"'s timestamp MUST be a signed integer that
represents the "Raw Timestamp" relative to the "Cluster"'s "Timestamp
Element", multiplied by the "TimestampScale Element". See
Section 25.4 for more information.
The "Block Element"'s timestamp MUST be represented by a 16bit signed
integer (sint16). The "Block"'s timestamp has a range of -32768 to
+32767 units. When using the default value of the "TimestampScale
Element", each integer represents 1ms. The maximum time span of
"Block Elements" in a "Cluster" using the default "TimestampScale
Element" of 1ms is 65536ms.
If a "Cluster"'s "Timestamp Element" is set to zero, it is possible
to have "Block Elements" with a negative "Raw Timestamp". "Block
Elements" with a negative "Raw Timestamp" are not valid.
25.3. Raw Timestamp
The exact time of an object SHOULD be represented in nanoseconds. To
find out a "Block"'s "Raw Timestamp", you need the "Block"'s
"Timestamp Element", the "Cluster"'s "Timestamp Element", and the
"TimestampScale Element".
25.4. TimestampScale
The "TimestampScale Element" is used to calculate the "Raw Timestamp"
of a "Block". The timestamp is obtained by adding the "Block"'s
timestamp to the "Cluster"'s "Timestamp Element", and then
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multiplying that result by the "TimestampScale". The result will be
the "Block"'s "Raw Timestamp" in nanoseconds. The formula for this
would look like:
(a + b) * c
a = `Block`'s Timestamp
b = `Cluster`'s Timestamp
c = `TimestampScale`
For example, assume a "Cluster"'s "Timestamp" has a value of 564264,
the "Block" has a "Timestamp" of 1233, and the "TimestampScale
Element" is the default of 1000000.
(1233 + 564264) * 1000000 = 565497000000
So, the "Block" in this example has a specific time of 565497000000
in nanoseconds. In milliseconds this would be 565497ms.
25.5. TimestampScale Rounding
Because the default value of "TimestampScale" is 1000000, which makes
each integer in the "Cluster" and "Block" "Timestamp Elements" equal
1ms, this is the most commonly used. When dealing with audio, this
causes inaccuracy when seeking. When the audio is combined with
video, this is not an issue. For most cases, the the synch of audio
to video does not need to be more than 1ms accurate. This becomes
obvious when one considers that sound will take 2-3ms to travel a
single meter, so distance from your speakers will have a greater
effect on audio/visual synch than this.
However, when dealing with audio-only files, seeking accuracy can
become critical. For instance, when storing a whole CD in a single
track, a user will want to be able to seek to the exact sample that a
song begins at. If seeking a few sample ahead or behind, a 'crack'
or 'pop' may result as a few odd samples are rendered. Also, when
performing precise editing, it may be very useful to have the audio
accuracy down to a single sample.
When storing timestamps for an audio stream, the "TimestampScale
Element" SHOULD have an accuracy of at least that of the audio sample
rate, otherwise there are rounding errors that prevent users from
knowing the precise location of a sample. Here's how a program has
to round each timestamp in order to be able to recreate the sample
number accurately.
Let's assume that the application has an audio track with a sample
rate of 44100. As written above the "TimestampScale" MUST have at
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least the accuracy of the sample rate itself: 1000000000 / 44100 =
22675.7369614512. This value MUST always be truncated. Otherwise
the accuracy will not suffice. So in this example the application
will use 22675 for the "TimestampScale". The application could even
use some lower value like 22674 which would allow it to be a little
bit imprecise about the original timestamps. But more about that in
a minute.
Next the application wants to write sample number 52340 and
calculates the timestamp. This is easy. In order to calculate the
"Raw Timestamp" in ns all it has to do is calculate "Raw Timestamp =
round(1000000000 * sample_number / sample_rate)". Rounding at this
stage is very important! The application might skip it if it choses
a slightly smaller value for the "TimestampScale" factor instead of
the truncated one like shown above. Otherwise it has to round or the
results won't be reversible. For our example we get "Raw Timestamp =
round(1000000000 * 52340 / 44100) = round(1186848072.56236) =
1186848073".
The next step is to calculate the "Absolute Timestamp" - that is the
timestamp that will be stored in the Matroska file. Here the
application has to divide the "Raw Timestamp" from the previous
paragraph by the "TimestampScale" factor and round the result:
"Absolute Timestamp = round(Raw Timestamp / TimestampScale_factor)"
which will result in the following for our example: "Absolute
Timestamp = round(1186848073 / 22675) = round(52341.7011245866) =
52342". This number is the one the application has to write to the
file.
Now our file is complete, and we want to play it back with another
application. Its task is to find out which sample the first
application wrote into the file. So it starts reading the Matroska
file and finds the "TimestampScale" factor 22675 and the audio sample
rate 44100. Later it finds a data block with the "Absolute
Timestamp" of 52342. But how does it get the sample number from
these numbers?
First it has to calculate the "Raw Timestamp" of the block it has
just read. Here's no rounding involved, just an integer
multiplication: "Raw Timestamp = Absolute Timestamp *
TimestampScale_factor". In our example: "Raw Timestamp = 52342 *
22675 = 1186854850".
The conversion from the "Raw Timestamp" to the sample number again
requires rounding: "sample_number = round(Raw Timestamp * sample_rate
/ 1000000000)". In our example: "sample_number = round(1186854850 *
44100 / 1000000000) = round(52340.298885) = 52340". This is exactly
the sample number that the previous program started with.
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Some general notes for a program:
1. Always calculate the timestamps / sample numbers with floating
point numbers of at least 64bit precision (called 'double' in
most modern programming languages). If you're calculating with
integers then make sure they're 64bit long, too.
2. Always round if you divide. Always! If you don't you'll end up
with situations in which you have a timestamp in the Matroska
file that does not correspond to the sample number that it
started with. Using a slightly lower timestamp scale factor can
help here in that it removes the need for proper rounding in the
conversion from sample number to "Raw Timestamp".
25.6. TrackTimestampScale
The "TrackTimestampScale Element" is used align tracks that would
otherwise be played at different speeds. An example of this would be
if you have a film that was originally recorded at 24fps video. When
playing this back through a PAL broadcasting system, it is standard
to speed up the film to 25fps to match the 25fps display speed of the
PAL broadcasting standard. However, when broadcasting the video
through NTSC, it is typical to leave the film at its original speed.
If you wanted to make a single file where there was one video stream,
and an audio stream used from the PAL broadcast, as well as an audio
stream used from the NTSC broadcast, you would have the problem that
the PAL audio stream would be 1/24th faster than the NTSC audio
stream, quickly leading to problems. It is possible to stretch out
the PAL audio track and re-encode it at a slower speed, however when
dealing with lossy audio codecs, this often results in a loss of
audio quality and/or larger file sizes.
This is the type of problem that "TrackTimestampScale" was designed
to fix. Using it, the video can be played back at a speed that will
synch with either the NTSC or the PAL audio stream, depending on
which is being used for playback. To continue the above example:
Track 1: Video
Track 2: NTSC Audio
Track 3: PAL Audio
Because the NTSC track is at the original speed, it will used as the
default value of 1.0 for its "TrackTimestampScale". The video will
also be aligned to the NTSC track with the default value of 1.0.
The "TrackTimestampScale" value to use for the PAL track would be
calculated by determining how much faster the PAL track is than the
NTSC track. In this case, because we know the video for the NTSC
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audio is being played back at 24fps and the video for the PAL audio
is being played back at 25fps, the calculation would be:
25/24 &#8776; 1.04166666666666666667
When writing a file that uses a non-default "TrackTimestampScale",
the values of the "Block"'s timestamp are whatever they would be when
normally storing the track with a default value for the
"TrackTimestampScale". However, the data is interleaved a little
differently. Data SHOULD be interleaved by its Section 25.3 in the
order handed back from the encoder. The "Raw Timestamp" of a "Block"
from a track using "TrackTimestampScale" is calculated using:
"(Block's Timestamp + Cluster's Timestamp) * TimestampScale *
TrackTimestampScale"
So, a Block from the PAL track above that had a Section 25.1 of 100
seconds would have a "Raw Timestamp" of 104.66666667 seconds, and so
would be stored in that part of the file.
When playing back a track using the "TrackTimestampScale", if the
track is being played by itself, there is no need to scale it. From
the above example, when playing the Video with the NTSC Audio,
neither are scaled. However, when playing back the Video with the
PAL Audio, the timestamps from the PAL Audio track are scaled using
the "TrackTimestampScale", resulting in the video playing back in
synch with the audio.
It would be possible for a "Matroska Player" to also adjust the
audio's samplerate at the same time as adjusting the timestamps if
you wanted to play the two audio streams synchronously. It would
also be possible to adjust the video to match the audio's speed.
However, for playback, the selected track(s) timestamps SHOULD be
adjusted if they need to be scaled.
While the above example deals specifically with audio tracks, this
element can be used to align video, audio, subtitles, or any other
type of track contained in a Matroska file.
26. References
26.1. URIs
[1] http://mukoli.free.fr/mcf/mcf.html
[2] https://github.com/Matroska-Org/ebml-specification/blob/master/
specification.markdown
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[3] https://datatracker.ietf.org/wg/cellar/charter/
[4] https://matroska.org/files/matroska.pdf
[5] diagram.md
[6] https://github.com/Matroska-Org/ebml-specification/blob/master/
specification.markdown
[7] https://github.com/Matroska-Org/foundation-
source/blob/master/spectool/specdata.xml
[8] https://tools.ietf.org/html/rfc2119
[9] https://github.com/Matroska-Org/ebml-specification/blob/master/
specification.markdown
[10] https://github.com/Matroska-Org/ebml-specification/blob/master/
specification.markdown#ebml-element-types
[11] https://github.com/Matroska-Org/ebml-specification/blob/master/
specification.markdown#ebml-schema
[12] https://github.com/Matroska-Org/ebml-specification/blob/master/
specification.markdown#structure
[13] https://www.loc.gov/standards/iso639-2/php/English_list.php
[14] https://tools.ietf.org/html/bcp47
[15] https://www.iana.org/domains/root/db
[16] http://www.webmproject.org/docs/container/
[17] http://dvd.sourceforge.net/dvdinfo/uops.html
[18] http://www.dvd-replica.com/DVD/
[19] http://dvd.sourceforge.net/dvdinfo/
[20] http://www.matroska.org/node/1/revisions/74/view#StereoMode
Authors' Addresses
Steve Lhomme
Email: slhomme@matroska.org
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Moritz Bunkus
Email: moritz@bunkus.org
Dave Rice
Email: dave@dericed.com
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