Matroska
draft-lhomme-cellar-matroska-03
The information below is for an old version of the document.
| Document | Type |
This is an older version of an Internet-Draft whose latest revision state is "Expired".
|
|
|---|---|---|---|
| Authors | Steve Lhomme, Moritz Bunkus, Dave Rice | ||
| Last updated | 2017-07-03 | ||
| RFC stream | (None) | ||
| Formats | |||
| Additional resources | |||
| Stream | Stream state | (No stream defined) | |
| Consensus boilerplate | Unknown | ||
| RFC Editor Note | (None) | ||
| IESG | IESG state | I-D Exists | |
| Telechat date | (None) | ||
| Responsible AD | (None) | ||
| Send notices to | (None) |
draft-lhomme-cellar-matroska-03
cellar S. Lhomme
Internet-Draft
Intended status: Standards Track M. Bunkus
Expires: January 4, 2018
D. Rice
July 3, 2017
Matroska
draft-lhomme-cellar-matroska-03
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 http://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 4, 2018.
Copyright Notice
Copyright (c) 2017 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
(http://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 . . . . . . . . . . . . . . . . . . . . . . . . 11
2. Status of this document . . . . . . . . . . . . . . . . . . . 12
3. Security Considerations . . . . . . . . . . . . . . . . . . . 13
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
5. Notations and Conventions . . . . . . . . . . . . . . . . . . 13
6. Basis in EBML . . . . . . . . . . . . . . . . . . . . . . . . 13
6.1. Added Constraints on EBML . . . . . . . . . . . . . . . . 13
6.2. Matroska Design . . . . . . . . . . . . . . . . . . . . . 14
6.2.1. Language Codes . . . . . . . . . . . . . . . . . . . 14
6.2.2. Physical Types . . . . . . . . . . . . . . . . . . . 14
6.2.3. Block Structure . . . . . . . . . . . . . . . . . . . 15
6.2.4. Lacing . . . . . . . . . . . . . . . . . . . . . . . 17
7. Matroska Structure . . . . . . . . . . . . . . . . . . . . . 20
7.1. Matroska Top Level Elements . . . . . . . . . . . . . . . 22
7.2. Matroska Additions to Schema Element Attributes . . . . . 29
7.3. Matroska Schema . . . . . . . . . . . . . . . . . . . . . 30
7.3.1. EBMLMaxIDLength Element . . . . . . . . . . . . . . . 30
7.3.2. EBMLMaxSizeLength Element . . . . . . . . . . . . . . 30
7.3.3. Segment Element . . . . . . . . . . . . . . . . . . . 31
7.3.4. SeekHead Element . . . . . . . . . . . . . . . . . . 31
7.3.5. Seek Element . . . . . . . . . . . . . . . . . . . . 31
7.3.6. SeekID Element . . . . . . . . . . . . . . . . . . . 32
7.3.7. SeekPosition Element . . . . . . . . . . . . . . . . 32
7.3.8. Info Element . . . . . . . . . . . . . . . . . . . . 33
7.3.9. SegmentUID Element . . . . . . . . . . . . . . . . . 33
7.3.10. SegmentFilename Element . . . . . . . . . . . . . . . 33
7.3.11. PrevUID Element . . . . . . . . . . . . . . . . . . . 34
7.3.12. PrevFilename Element . . . . . . . . . . . . . . . . 34
7.3.13. NextUID Element . . . . . . . . . . . . . . . . . . . 35
7.3.14. NextFilename Element . . . . . . . . . . . . . . . . 35
7.3.15. SegmentFamily Element . . . . . . . . . . . . . . . . 36
7.3.16. ChapterTranslate Element . . . . . . . . . . . . . . 36
7.3.17. ChapterTranslateEditionUID Element . . . . . . . . . 36
7.3.18. ChapterTranslateCodec Element . . . . . . . . . . . . 37
7.3.19. ChapterTranslateID Element . . . . . . . . . . . . . 37
7.3.20. TimecodeScale Element . . . . . . . . . . . . . . . . 38
7.3.21. Duration Element . . . . . . . . . . . . . . . . . . 38
7.3.22. DateUTC Element . . . . . . . . . . . . . . . . . . . 38
7.3.23. Title Element . . . . . . . . . . . . . . . . . . . . 39
7.3.24. MuxingApp Element . . . . . . . . . . . . . . . . . . 39
7.3.25. WritingApp Element . . . . . . . . . . . . . . . . . 40
7.3.26. Cluster Element . . . . . . . . . . . . . . . . . . . 40
7.3.27. Timecode Element . . . . . . . . . . . . . . . . . . 40
7.3.28. SilentTracks Element . . . . . . . . . . . . . . . . 41
7.3.29. SilentTrackNumber Element . . . . . . . . . . . . . . 41
7.3.30. Position Element . . . . . . . . . . . . . . . . . . 41
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7.3.31. PrevSize Element . . . . . . . . . . . . . . . . . . 42
7.3.32. SimpleBlock Element . . . . . . . . . . . . . . . . . 42
7.3.33. BlockGroup Element . . . . . . . . . . . . . . . . . 43
7.3.34. Block Element . . . . . . . . . . . . . . . . . . . . 43
7.3.35. BlockVirtual Element . . . . . . . . . . . . . . . . 43
7.3.36. BlockAdditions Element . . . . . . . . . . . . . . . 44
7.3.37. BlockMore Element . . . . . . . . . . . . . . . . . . 44
7.3.38. BlockAddID Element . . . . . . . . . . . . . . . . . 44
7.3.39. BlockAdditional Element . . . . . . . . . . . . . . . 45
7.3.40. BlockDuration Element . . . . . . . . . . . . . . . . 45
7.3.41. ReferencePriority Element . . . . . . . . . . . . . . 46
7.3.42. ReferenceBlock Element . . . . . . . . . . . . . . . 46
7.3.43. ReferenceVirtual Element . . . . . . . . . . . . . . 47
7.3.44. CodecState Element . . . . . . . . . . . . . . . . . 47
7.3.45. DiscardPadding Element . . . . . . . . . . . . . . . 47
7.3.46. Slices Element . . . . . . . . . . . . . . . . . . . 48
7.3.47. TimeSlice Element . . . . . . . . . . . . . . . . . . 48
7.3.48. LaceNumber Element . . . . . . . . . . . . . . . . . 49
7.3.49. FrameNumber Element . . . . . . . . . . . . . . . . . 49
7.3.50. BlockAdditionID Element . . . . . . . . . . . . . . . 50
7.3.51. Delay Element . . . . . . . . . . . . . . . . . . . . 50
7.3.52. SliceDuration Element . . . . . . . . . . . . . . . . 50
7.3.53. ReferenceFrame Element . . . . . . . . . . . . . . . 51
7.3.54. ReferenceOffset Element . . . . . . . . . . . . . . . 51
7.3.55. ReferenceTimeCode Element . . . . . . . . . . . . . . 52
7.3.56. EncryptedBlock Element . . . . . . . . . . . . . . . 52
7.3.57. Tracks Element . . . . . . . . . . . . . . . . . . . 52
7.3.58. TrackEntry Element . . . . . . . . . . . . . . . . . 53
7.3.59. TrackNumber Element . . . . . . . . . . . . . . . . . 53
7.3.60. TrackUID Element . . . . . . . . . . . . . . . . . . 54
7.3.61. TrackType Element . . . . . . . . . . . . . . . . . . 54
7.3.62. FlagEnabled Element . . . . . . . . . . . . . . . . . 54
7.3.63. FlagDefault Element . . . . . . . . . . . . . . . . . 55
7.3.64. FlagForced Element . . . . . . . . . . . . . . . . . 55
7.3.65. FlagLacing Element . . . . . . . . . . . . . . . . . 56
7.3.66. MinCache Element . . . . . . . . . . . . . . . . . . 56
7.3.67. MaxCache Element . . . . . . . . . . . . . . . . . . 57
7.3.68. DefaultDuration Element . . . . . . . . . . . . . . . 57
7.3.69. DefaultDecodedFieldDuration Element . . . . . . . . . 58
7.3.70. TrackTimecodeScale Element . . . . . . . . . . . . . 58
7.3.71. TrackOffset Element . . . . . . . . . . . . . . . . . 59
7.3.72. MaxBlockAdditionID Element . . . . . . . . . . . . . 59
7.3.73. Name Element . . . . . . . . . . . . . . . . . . . . 59
7.3.74. Language Element . . . . . . . . . . . . . . . . . . 60
7.3.75. LanguageIETF Element . . . . . . . . . . . . . . . . 60
7.3.76. CodecID Element . . . . . . . . . . . . . . . . . . . 61
7.3.77. CodecPrivate Element . . . . . . . . . . . . . . . . 61
7.3.78. CodecName Element . . . . . . . . . . . . . . . . . . 61
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7.3.79. AttachmentLink Element . . . . . . . . . . . . . . . 62
7.3.80. CodecSettings Element . . . . . . . . . . . . . . . . 62
7.3.81. CodecInfoURL Element . . . . . . . . . . . . . . . . 62
7.3.82. CodecDownloadURL Element . . . . . . . . . . . . . . 63
7.3.83. CodecDecodeAll Element . . . . . . . . . . . . . . . 63
7.3.84. TrackOverlay Element . . . . . . . . . . . . . . . . 64
7.3.85. CodecDelay Element . . . . . . . . . . . . . . . . . 64
7.3.86. SeekPreRoll Element . . . . . . . . . . . . . . . . . 64
7.3.87. TrackTranslate Element . . . . . . . . . . . . . . . 65
7.3.88. TrackTranslateEditionUID Element . . . . . . . . . . 65
7.3.89. TrackTranslateCodec Element . . . . . . . . . . . . . 65
7.3.90. TrackTranslateTrackID Element . . . . . . . . . . . . 66
7.3.91. Video Element . . . . . . . . . . . . . . . . . . . . 66
7.3.92. FlagInterlaced Element . . . . . . . . . . . . . . . 67
7.3.93. FieldOrder Element . . . . . . . . . . . . . . . . . 67
7.3.94. StereoMode Element . . . . . . . . . . . . . . . . . 68
7.3.95. AlphaMode Element . . . . . . . . . . . . . . . . . . 68
7.3.96. OldStereoMode Element . . . . . . . . . . . . . . . . 68
7.3.97. PixelWidth Element . . . . . . . . . . . . . . . . . 69
7.3.98. PixelHeight Element . . . . . . . . . . . . . . . . . 69
7.3.99. PixelCropBottom Element . . . . . . . . . . . . . . . 70
7.3.100. PixelCropTop Element . . . . . . . . . . . . . . . . 70
7.3.101. PixelCropLeft Element . . . . . . . . . . . . . . . 70
7.3.102. PixelCropRight Element . . . . . . . . . . . . . . . 71
7.3.103. DisplayWidth Element . . . . . . . . . . . . . . . . 71
7.3.104. DisplayHeight Element . . . . . . . . . . . . . . . 72
7.3.105. DisplayUnit Element . . . . . . . . . . . . . . . . 72
7.3.106. AspectRatioType Element . . . . . . . . . . . . . . 73
7.3.107. ColourSpace Element . . . . . . . . . . . . . . . . 73
7.3.108. GammaValue Element . . . . . . . . . . . . . . . . . 73
7.3.109. FrameRate Element . . . . . . . . . . . . . . . . . 74
7.3.110. Colour Element . . . . . . . . . . . . . . . . . . . 74
7.3.111. MatrixCoefficients Element . . . . . . . . . . . . . 75
7.3.112. BitsPerChannel Element . . . . . . . . . . . . . . . 75
7.3.113. ChromaSubsamplingHorz Element . . . . . . . . . . . 75
7.3.114. ChromaSubsamplingVert Element . . . . . . . . . . . 76
7.3.115. CbSubsamplingHorz Element . . . . . . . . . . . . . 76
7.3.116. CbSubsamplingVert Element . . . . . . . . . . . . . 77
7.3.117. ChromaSitingHorz Element . . . . . . . . . . . . . . 77
7.3.118. ChromaSitingVert Element . . . . . . . . . . . . . . 77
7.3.119. Range Element . . . . . . . . . . . . . . . . . . . 78
7.3.120. TransferCharacteristics Element . . . . . . . . . . 78
7.3.121. Primaries Element . . . . . . . . . . . . . . . . . 79
7.3.122. MaxCLL Element . . . . . . . . . . . . . . . . . . . 79
7.3.123. MaxFALL Element . . . . . . . . . . . . . . . . . . 79
7.3.124. MasteringMetadata Element . . . . . . . . . . . . . 80
7.3.125. PrimaryRChromaticityX Element . . . . . . . . . . . 80
7.3.126. PrimaryRChromaticityY Element . . . . . . . . . . . 81
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7.3.127. PrimaryGChromaticityX Element . . . . . . . . . . . 81
7.3.128. PrimaryGChromaticityY Element . . . . . . . . . . . 81
7.3.129. PrimaryBChromaticityX Element . . . . . . . . . . . 82
7.3.130. PrimaryBChromaticityY Element . . . . . . . . . . . 82
7.3.131. WhitePointChromaticityX Element . . . . . . . . . . 83
7.3.132. WhitePointChromaticityY Element . . . . . . . . . . 83
7.3.133. LuminanceMax Element . . . . . . . . . . . . . . . . 83
7.3.134. LuminanceMin Element . . . . . . . . . . . . . . . . 84
7.3.135. Projection Element . . . . . . . . . . . . . . . . . 84
7.3.136. ProjectionType Element . . . . . . . . . . . . . . . 85
7.3.137. ProjectionPrivate Element . . . . . . . . . . . . . 85
7.3.138. ProjectionPoseYaw Element . . . . . . . . . . . . . 86
7.3.139. ProjectionPosePitch Element . . . . . . . . . . . . 86
7.3.140. ProjectionPoseRoll Element . . . . . . . . . . . . . 87
7.3.141. Audio Element . . . . . . . . . . . . . . . . . . . 87
7.3.142. SamplingFrequency Element . . . . . . . . . . . . . 88
7.3.143. OutputSamplingFrequency Element . . . . . . . . . . 88
7.3.144. Channels Element . . . . . . . . . . . . . . . . . . 89
7.3.145. ChannelPositions Element . . . . . . . . . . . . . . 89
7.3.146. BitDepth Element . . . . . . . . . . . . . . . . . . 89
7.3.147. TrackOperation Element . . . . . . . . . . . . . . . 90
7.3.148. TrackCombinePlanes Element . . . . . . . . . . . . . 90
7.3.149. TrackPlane Element . . . . . . . . . . . . . . . . . 91
7.3.150. TrackPlaneUID Element . . . . . . . . . . . . . . . 91
7.3.151. TrackPlaneType Element . . . . . . . . . . . . . . . 91
7.3.152. TrackJoinBlocks Element . . . . . . . . . . . . . . 92
7.3.153. TrackJoinUID Element . . . . . . . . . . . . . . . . 92
7.3.154. TrickTrackUID Element . . . . . . . . . . . . . . . 93
7.3.155. TrickTrackSegmentUID Element . . . . . . . . . . . . 93
7.3.156. TrickTrackFlag Element . . . . . . . . . . . . . . . 93
7.3.157. TrickMasterTrackUID Element . . . . . . . . . . . . 94
7.3.158. TrickMasterTrackSegmentUID Element . . . . . . . . . 94
7.3.159. ContentEncodings Element . . . . . . . . . . . . . . 95
7.3.160. ContentEncoding Element . . . . . . . . . . . . . . 95
7.3.161. ContentEncodingOrder Element . . . . . . . . . . . . 95
7.3.162. ContentEncodingScope Element . . . . . . . . . . . . 96
7.3.163. ContentEncodingType Element . . . . . . . . . . . . 96
7.3.164. ContentCompression Element . . . . . . . . . . . . . 97
7.3.165. ContentCompAlgo Element . . . . . . . . . . . . . . 97
7.3.166. ContentCompSettings Element . . . . . . . . . . . . 98
7.3.167. ContentEncryption Element . . . . . . . . . . . . . 98
7.3.168. ContentEncAlgo Element . . . . . . . . . . . . . . . 99
7.3.169. ContentEncKeyID Element . . . . . . . . . . . . . . 99
7.3.170. ContentSignature Element . . . . . . . . . . . . . . 99
7.3.171. ContentSigKeyID Element . . . . . . . . . . . . . . 100
7.3.172. ContentSigAlgo Element . . . . . . . . . . . . . . . 100
7.3.173. ContentSigHashAlgo Element . . . . . . . . . . . . . 101
7.3.174. Cues Element . . . . . . . . . . . . . . . . . . . . 101
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7.3.175. CuePoint Element . . . . . . . . . . . . . . . . . . 101
7.3.176. CueTime Element . . . . . . . . . . . . . . . . . . 102
7.3.177. CueTrackPositions Element . . . . . . . . . . . . . 102
7.3.178. CueTrack Element . . . . . . . . . . . . . . . . . . 102
7.3.179. CueClusterPosition Element . . . . . . . . . . . . . 103
7.3.180. CueRelativePosition Element . . . . . . . . . . . . 103
7.3.181. CueDuration Element . . . . . . . . . . . . . . . . 104
7.3.182. CueBlockNumber Element . . . . . . . . . . . . . . . 104
7.3.183. CueCodecState Element . . . . . . . . . . . . . . . 104
7.3.184. CueReference Element . . . . . . . . . . . . . . . . 105
7.3.185. CueRefTime Element . . . . . . . . . . . . . . . . . 105
7.3.186. CueRefCluster Element . . . . . . . . . . . . . . . 106
7.3.187. CueRefNumber Element . . . . . . . . . . . . . . . . 106
7.3.188. CueRefCodecState Element . . . . . . . . . . . . . . 107
7.3.189. Attachments Element . . . . . . . . . . . . . . . . 107
7.3.190. AttachedFile Element . . . . . . . . . . . . . . . . 107
7.3.191. FileDescription Element . . . . . . . . . . . . . . 108
7.3.192. FileName Element . . . . . . . . . . . . . . . . . . 108
7.3.193. FileMimeType Element . . . . . . . . . . . . . . . . 108
7.3.194. FileData Element . . . . . . . . . . . . . . . . . . 109
7.3.195. FileUID Element . . . . . . . . . . . . . . . . . . 109
7.3.196. FileReferral Element . . . . . . . . . . . . . . . . 110
7.3.197. FileUsedStartTime Element . . . . . . . . . . . . . 110
7.3.198. FileUsedEndTime Element . . . . . . . . . . . . . . 110
7.3.199. Chapters Element . . . . . . . . . . . . . . . . . . 111
7.3.200. EditionEntry Element . . . . . . . . . . . . . . . . 111
7.3.201. EditionUID Element . . . . . . . . . . . . . . . . . 111
7.3.202. EditionFlagHidden Element . . . . . . . . . . . . . 112
7.3.203. EditionFlagDefault Element . . . . . . . . . . . . . 112
7.3.204. EditionFlagOrdered Element . . . . . . . . . . . . . 113
7.3.205. ChapterAtom Element . . . . . . . . . . . . . . . . 113
7.3.206. ChapterUID Element . . . . . . . . . . . . . . . . . 114
7.3.207. ChapterStringUID Element . . . . . . . . . . . . . . 114
7.3.208. ChapterTimeStart Element . . . . . . . . . . . . . . 114
7.3.209. ChapterTimeEnd Element . . . . . . . . . . . . . . . 115
7.3.210. ChapterFlagHidden Element . . . . . . . . . . . . . 115
7.3.211. ChapterFlagEnabled Element . . . . . . . . . . . . . 116
7.3.212. ChapterSegmentUID Element . . . . . . . . . . . . . 116
7.3.213. ChapterSegmentEditionUID Element . . . . . . . . . . 117
7.3.214. ChapterPhysicalEquiv Element . . . . . . . . . . . . 117
7.3.215. ChapterTrack Element . . . . . . . . . . . . . . . . 118
7.3.216. ChapterTrackNumber Element . . . . . . . . . . . . . 118
7.3.217. ChapterDisplay Element . . . . . . . . . . . . . . . 118
7.3.218. ChapString Element . . . . . . . . . . . . . . . . . 119
7.3.219. ChapLanguage Element . . . . . . . . . . . . . . . . 119
7.3.220. ChapLanguageIETF Element . . . . . . . . . . . . . . 120
7.3.221. ChapCountry Element . . . . . . . . . . . . . . . . 120
7.3.222. ChapProcess Element . . . . . . . . . . . . . . . . 120
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7.3.223. ChapProcessCodecID Element . . . . . . . . . . . . . 121
7.3.224. ChapProcessPrivate Element . . . . . . . . . . . . . 121
7.3.225. ChapProcessCommand Element . . . . . . . . . . . . . 122
7.3.226. ChapProcessTime Element . . . . . . . . . . . . . . 122
7.3.227. ChapProcessData Element . . . . . . . . . . . . . . 122
7.3.228. Tags Element . . . . . . . . . . . . . . . . . . . . 123
7.3.229. Tag Element . . . . . . . . . . . . . . . . . . . . 123
7.3.230. Targets Element . . . . . . . . . . . . . . . . . . 123
7.3.231. TargetTypeValue Element . . . . . . . . . . . . . . 124
7.3.232. TargetType Element . . . . . . . . . . . . . . . . . 124
7.3.233. TagTrackUID Element . . . . . . . . . . . . . . . . 125
7.3.234. TagEditionUID Element . . . . . . . . . . . . . . . 125
7.3.235. TagChapterUID Element . . . . . . . . . . . . . . . 125
7.3.236. TagAttachmentUID Element . . . . . . . . . . . . . . 126
7.3.237. SimpleTag Element . . . . . . . . . . . . . . . . . 126
7.3.238. TagName Element . . . . . . . . . . . . . . . . . . 126
7.3.239. TagLanguage Element . . . . . . . . . . . . . . . . 127
7.3.240. TagLanguageIETF Element . . . . . . . . . . . . . . 127
7.3.241. TagDefault Element . . . . . . . . . . . . . . . . . 128
7.3.242. TagString Element . . . . . . . . . . . . . . . . . 128
7.3.243. TagBinary Element . . . . . . . . . . . . . . . . . 129
8. Beginning of File . . . . . . . . . . . . . . . . . . . . . . 129
9. Block Timecodes . . . . . . . . . . . . . . . . . . . . . . . 129
10. Default decoded field duration . . . . . . . . . . . . . . . 130
11. Default Values . . . . . . . . . . . . . . . . . . . . . . . 130
12. DRM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
13. Encryption . . . . . . . . . . . . . . . . . . . . . . . . . 131
14. Image cropping . . . . . . . . . . . . . . . . . . . . . . . 131
15. Matroska version indicators . . . . . . . . . . . . . . . . . 131
16. Mime Types . . . . . . . . . . . . . . . . . . . . . . . . . 132
17. Octet . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
18. Overlay Track . . . . . . . . . . . . . . . . . . . . . . . . 132
19. Segment Position . . . . . . . . . . . . . . . . . . . . . . 132
19.1. Segment Position Exception . . . . . . . . . . . . . . . 133
19.2. Example of Segment Position . . . . . . . . . . . . . . 133
20. Raw Timecode . . . . . . . . . . . . . . . . . . . . . . . . 133
21. Linked Segments . . . . . . . . . . . . . . . . . . . . . . . 133
21.1. Hard Linking . . . . . . . . . . . . . . . . . . . . . . 134
21.2. Soft Linking . . . . . . . . . . . . . . . . . . . . . . 134
21.3. Medium Linking . . . . . . . . . . . . . . . . . . . . . 135
22. Timecode Types . . . . . . . . . . . . . . . . . . . . . . . 135
23. TimecodeScale . . . . . . . . . . . . . . . . . . . . . . . . 135
24. TimecodeScale Rounding . . . . . . . . . . . . . . . . . . . 136
25. Track Flags . . . . . . . . . . . . . . . . . . . . . . . . . 138
25.1. Default flag . . . . . . . . . . . . . . . . . . . . . . 138
25.2. Forced flag . . . . . . . . . . . . . . . . . . . . . . 138
26. TrackTimecodeScale . . . . . . . . . . . . . . . . . . . . . 138
27. Unknown elements . . . . . . . . . . . . . . . . . . . . . . 140
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28. Multi-planar and 3D videos . . . . . . . . . . . . . . . . . 140
29. Track Operation . . . . . . . . . . . . . . . . . . . . . . . 141
30. Matroska Element Ordering Guidelines . . . . . . . . . . . . 141
30.1. Top-Level Elements . . . . . . . . . . . . . . . . . . . 142
30.2. CRC-32 . . . . . . . . . . . . . . . . . . . . . . . . . 142
30.3. SeekHead . . . . . . . . . . . . . . . . . . . . . . . . 142
30.4. Cues (index) . . . . . . . . . . . . . . . . . . . . . . 143
30.5. Info . . . . . . . . . . . . . . . . . . . . . . . . . . 143
30.6. Chapters . . . . . . . . . . . . . . . . . . . . . . . . 143
30.7. Attachments . . . . . . . . . . . . . . . . . . . . . . 143
30.8. Tags . . . . . . . . . . . . . . . . . . . . . . . . . . 143
30.9. Optimum layout from a muxer . . . . . . . . . . . . . . 144
30.10. Optimum layout after editing tags . . . . . . . . . . . 144
30.11. Optimum layout with Cues at the front . . . . . . . . . 144
30.12. Cluster Timecode . . . . . . . . . . . . . . . . . . . . 145
31. Codec Mappings . . . . . . . . . . . . . . . . . . . . . . . 145
31.1. Defining Matroska Codec Support . . . . . . . . . . . . 145
31.1.1. Codec ID . . . . . . . . . . . . . . . . . . . . . . 145
31.1.2. Codec Name . . . . . . . . . . . . . . . . . . . . . 146
31.1.3. Description . . . . . . . . . . . . . . . . . . . . 146
31.1.4. Initialisation . . . . . . . . . . . . . . . . . . . 146
31.1.5. Citation . . . . . . . . . . . . . . . . . . . . . . 147
31.1.6. Deprecation Date . . . . . . . . . . . . . . . . . . 147
31.1.7. Superseded By . . . . . . . . . . . . . . . . . . . 147
31.2. Video Codec Mappings . . . . . . . . . . . . . . . . . . 147
31.2.1. V_MS/VFW/FOURCC . . . . . . . . . . . . . . . . . . 147
31.2.2. V_UNCOMPRESSED . . . . . . . . . . . . . . . . . . . 147
31.2.3. V_MPEG4/ISO/SP . . . . . . . . . . . . . . . . . . . 148
31.2.4. V_MPEG4/ISO/ASP . . . . . . . . . . . . . . . . . . 148
31.2.5. V_MPEG4/ISO/AP . . . . . . . . . . . . . . . . . . . 148
31.2.6. V_MPEG4/MS/V3 . . . . . . . . . . . . . . . . . . . 149
31.2.7. V_MPEG1 . . . . . . . . . . . . . . . . . . . . . . 149
31.2.8. V_MPEG2 . . . . . . . . . . . . . . . . . . . . . . 149
31.2.9. V_REAL/RV10 . . . . . . . . . . . . . . . . . . . . 149
31.2.10. V_REAL/RV20 . . . . . . . . . . . . . . . . . . . . 150
31.2.11. V_REAL/RV30 . . . . . . . . . . . . . . . . . . . . 150
31.2.12. V_REAL/RV40 . . . . . . . . . . . . . . . . . . . . 150
31.2.13. V_QUICKTIME . . . . . . . . . . . . . . . . . . . . 150
31.2.14. V_THEORA . . . . . . . . . . . . . . . . . . . . . . 151
31.2.15. V_PRORES . . . . . . . . . . . . . . . . . . . . . . 151
31.2.16. V_VP8 . . . . . . . . . . . . . . . . . . . . . . . 152
31.2.17. V_VP9 . . . . . . . . . . . . . . . . . . . . . . . 152
31.2.18. V_FFV1 . . . . . . . . . . . . . . . . . . . . . . . 152
31.3. Audio Codec Mappings . . . . . . . . . . . . . . . . . . 153
31.3.1. A_MPEG/L3 . . . . . . . . . . . . . . . . . . . . . 153
31.3.2. A_MPEG/L2 . . . . . . . . . . . . . . . . . . . . . 153
31.3.3. A_MPEG/L1 . . . . . . . . . . . . . . . . . . . . . 153
31.3.4. A_PCM/INT/BIG . . . . . . . . . . . . . . . . . . . 153
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31.3.5. A_PCM/INT/LIT . . . . . . . . . . . . . . . . . . . 154
31.3.6. A_PCM/FLOAT/IEEE . . . . . . . . . . . . . . . . . . 154
31.3.7. A_MPC . . . . . . . . . . . . . . . . . . . . . . . 154
31.3.8. A_AC3 . . . . . . . . . . . . . . . . . . . . . . . 154
31.3.9. A_AC3/BSID9 . . . . . . . . . . . . . . . . . . . . 155
31.3.10. A_AC3/BSID10 . . . . . . . . . . . . . . . . . . . . 155
31.3.11. A_ALAC . . . . . . . . . . . . . . . . . . . . . . . 155
31.3.12. A_DTS . . . . . . . . . . . . . . . . . . . . . . . 155
31.3.13. A_DTS/EXPRESS . . . . . . . . . . . . . . . . . . . 156
31.3.14. A_DTS/LOSSLESS . . . . . . . . . . . . . . . . . . . 156
31.3.15. A_VORBIS . . . . . . . . . . . . . . . . . . . . . . 156
31.3.16. A_FLAC . . . . . . . . . . . . . . . . . . . . . . . 157
31.3.17. A_REAL/14_4 . . . . . . . . . . . . . . . . . . . . 157
31.3.18. A_REAL/28_8 . . . . . . . . . . . . . . . . . . . . 157
31.3.19. A_REAL/COOK . . . . . . . . . . . . . . . . . . . . 157
31.3.20. A_REAL/SIPR . . . . . . . . . . . . . . . . . . . . 158
31.3.21. A_REAL/RALF . . . . . . . . . . . . . . . . . . . . 158
31.3.22. A_REAL/ATRC . . . . . . . . . . . . . . . . . . . . 158
31.3.23. A_MS/ACM . . . . . . . . . . . . . . . . . . . . . . 158
31.3.24. A_AAC/MPEG2/MAIN . . . . . . . . . . . . . . . . . . 159
31.3.25. A_AAC/MPEG2/LC . . . . . . . . . . . . . . . . . . . 159
31.3.26. A_AAC/MPEG2/LC/SBR . . . . . . . . . . . . . . . . . 159
31.3.27. A_AAC/MPEG2/SSR . . . . . . . . . . . . . . . . . . 159
31.3.28. A_AAC/MPEG4/MAIN . . . . . . . . . . . . . . . . . . 160
31.3.29. A_AAC/MPEG4/LC . . . . . . . . . . . . . . . . . . . 160
31.3.30. A_AAC/MPEG4/LC/SBR . . . . . . . . . . . . . . . . . 160
31.3.31. A_AAC/MPEG4/SSR . . . . . . . . . . . . . . . . . . 161
31.3.32. A_AAC/MPEG4/LTP . . . . . . . . . . . . . . . . . . 161
31.3.33. A_QUICKTIME . . . . . . . . . . . . . . . . . . . . 161
31.3.34. A_QUICKTIME/QDMC . . . . . . . . . . . . . . . . . . 161
31.3.35. A_QUICKTIME/QDM2 . . . . . . . . . . . . . . . . . . 162
31.3.36. A_TTA1 . . . . . . . . . . . . . . . . . . . . . . . 162
31.3.37. A_WAVPACK4 . . . . . . . . . . . . . . . . . . . . . 162
31.4. Subtitle Codec Mappings . . . . . . . . . . . . . . . . 163
31.4.1. S_TEXT/UTF8 . . . . . . . . . . . . . . . . . . . . 163
31.4.2. S_TEXT/SSA . . . . . . . . . . . . . . . . . . . . . 163
31.4.3. S_TEXT/ASS . . . . . . . . . . . . . . . . . . . . . 163
31.4.4. S_TEXT/USF . . . . . . . . . . . . . . . . . . . . . 163
31.4.5. S_TEXT/WEBVTT . . . . . . . . . . . . . . . . . . . 163
31.4.6. S_IMAGE/BMP . . . . . . . . . . . . . . . . . . . . 164
31.4.7. S_DVBSUB . . . . . . . . . . . . . . . . . . . . . . 164
31.4.8. S_VOBSUB . . . . . . . . . . . . . . . . . . . . . . 164
31.4.9. S_HDMV/PGS . . . . . . . . . . . . . . . . . . . . . 165
31.4.10. S_HDMV/TEXTST . . . . . . . . . . . . . . . . . . . 165
31.4.11. S_KATE . . . . . . . . . . . . . . . . . . . . . . . 165
31.5. Button Codec Mappings . . . . . . . . . . . . . . . . . 165
31.5.1. B_VOBBTN . . . . . . . . . . . . . . . . . . . . . . 165
31.6. Edition and Chapter Flags . . . . . . . . . . . . . . . 166
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31.6.1. Chapter Flags . . . . . . . . . . . . . . . . . . . 166
31.6.2. Edition Flags . . . . . . . . . . . . . . . . . . . 166
31.7. Menu features . . . . . . . . . . . . . . . . . . . . . 167
31.7.1. Matroska Script (0) . . . . . . . . . . . . . . . . 167
31.7.2. DVD menu (1) . . . . . . . . . . . . . . . . . . . . 167
31.8. Example 1 : basic chaptering . . . . . . . . . . . . . . 169
31.9. Example 2 : nested chapters . . . . . . . . . . . . . . 171
31.9.1. The Micronauts "Bleep To Bleep" . . . . . . . . . . 171
32. Subtitles . . . . . . . . . . . . . . . . . . . . . . . . . . 174
33. Images Subtitles . . . . . . . . . . . . . . . . . . . . . . 174
34. SRT Subtitles . . . . . . . . . . . . . . . . . . . . . . . . 177
35. SSA/ASS Subtitles . . . . . . . . . . . . . . . . . . . . . . 178
36. USF Subtitles . . . . . . . . . . . . . . . . . . . . . . . . 181
37. WebVTT . . . . . . . . . . . . . . . . . . . . . . . . . . . 181
37.1. Storage of WebVTT in Matroska . . . . . . . . . . . . . 182
37.1.1. CodecID: codec identification . . . . . . . . . . . 182
37.1.2. CodecPrivate: storage of gloal WebVTT blocks . . . . 182
37.1.3. Storage of non-global WebVTT blocks . . . . . . . . 182
37.1.4. Storage of Cues in Matroska blocks . . . . . . . . . 182
37.1.5. BlockAdditions: storing non-global WebVTT blocks,
Cue Settings Lists and Cue identifiers . . . . . . . 182
37.2. Examples of transformation . . . . . . . . . . . . . . . 183
37.2.1. Example WebVTT file . . . . . . . . . . . . . . . . 183
37.2.2. CodecPrivate . . . . . . . . . . . . . . . . . . . . 185
37.2.3. Storage of Cue 1 . . . . . . . . . . . . . . . . . . 185
37.2.4. Storage of Cue 2 . . . . . . . . . . . . . . . . . . 186
37.2.5. Storage of Cue 3 . . . . . . . . . . . . . . . . . . 186
37.2.6. Storage of Cue 4 . . . . . . . . . . . . . . . . . . 186
37.3. Storage of WebVTT in Matroska vs. WebM . . . . . . . . . 186
38. HDMV presentation graphics subtitles . . . . . . . . . . . . 187
38.1. Storage of HDMV presentation graphics subtitles . . . . 187
38.1.1. CodecID & CodecPrivate: codec identification . . . . 187
38.1.2. Storage of HDMV PGS Segments in Matroska Blocks . . 187
39. HDMV text subtitles . . . . . . . . . . . . . . . . . . . . . 187
39.1. Storage of HDMV text subtitles . . . . . . . . . . . . . 188
39.1.1. CodecID & CodecPrivate: codec identification . . . . 188
39.1.2. Storage of HDMV TextST Dialog Presentation Segments
in Matroska Blocks . . . . . . . . . . . . . . . . . 188
39.1.3. Character set . . . . . . . . . . . . . . . . . . . 188
40. Digital Video Broadcasting (DVB) subtitles . . . . . . . . . 188
40.1. Storage of DVB subtitles . . . . . . . . . . . . . . . . 189
40.1.1. CodecID . . . . . . . . . . . . . . . . . . . . . . 189
40.1.2. CodecPrivate . . . . . . . . . . . . . . . . . . . . 189
40.1.3. Storage of DVB subtitles in Matroska Blocks . . . . 189
41. Tagging . . . . . . . . . . . . . . . . . . . . . . . . . . . 189
41.1. Why official tags matter . . . . . . . . . . . . . . . . 190
41.2. Tag translations . . . . . . . . . . . . . . . . . . . . 191
41.3. Tag Formatting . . . . . . . . . . . . . . . . . . . . . 191
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41.4. Target types . . . . . . . . . . . . . . . . . . . . . . 191
41.5. Official tags . . . . . . . . . . . . . . . . . . . . . 192
41.6. Nesting Information . . . . . . . . . . . . . . . . . . 192
41.7. Organization Information . . . . . . . . . . . . . . . . 193
41.8. Titles . . . . . . . . . . . . . . . . . . . . . . . . . 193
41.9. Nested Information . . . . . . . . . . . . . . . . . . . 194
41.10. Entities . . . . . . . . . . . . . . . . . . . . . . . . 194
41.11. Search and Classification . . . . . . . . . . . . . . . 196
41.12. Temporal Information . . . . . . . . . . . . . . . . . . 198
41.13. Spacial Information . . . . . . . . . . . . . . . . . . 198
41.14. Personal . . . . . . . . . . . . . . . . . . . . . . . . 199
41.15. Technical Information . . . . . . . . . . . . . . . . . 200
41.16. Identifiers . . . . . . . . . . . . . . . . . . . . . . 202
41.17. Commercial . . . . . . . . . . . . . . . . . . . . . . . 202
41.18. Legal . . . . . . . . . . . . . . . . . . . . . . . . . 203
41.19. Notes . . . . . . . . . . . . . . . . . . . . . . . . . 203
42. Attachments . . . . . . . . . . . . . . . . . . . . . . . . . 204
42.1. Introduction . . . . . . . . . . . . . . . . . . . . . . 204
42.2. Cover Art . . . . . . . . . . . . . . . . . . . . . . . 204
42.3. Font files . . . . . . . . . . . . . . . . . . . . . . . 205
43. Cues . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
43.1. Introduction . . . . . . . . . . . . . . . . . . . . . . 205
43.2. Recommendations . . . . . . . . . . . . . . . . . . . . 205
44. Matroska Streaming . . . . . . . . . . . . . . . . . . . . . 206
45. File Access . . . . . . . . . . . . . . . . . . . . . . . . . 206
46. Live Streaming . . . . . . . . . . . . . . . . . . . . . . . 206
47. Menu Specifications . . . . . . . . . . . . . . . . . . . . . 207
48. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 207
49. Requirements . . . . . . . . . . . . . . . . . . . . . . . . 207
49.1. Highlights/Hotspots . . . . . . . . . . . . . . . . . . 207
49.2. Playback features . . . . . . . . . . . . . . . . . . . 208
49.3. Player requirements . . . . . . . . . . . . . . . . . . 209
50. Working Graph . . . . . . . . . . . . . . . . . . . . . . . . 209
51. Ideas . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209
52. Data Structure . . . . . . . . . . . . . . . . . . . . . . . 209
53. References . . . . . . . . . . . . . . . . . . . . . . . . . 209
53.1. Normative References . . . . . . . . . . . . . . . . . . 209
53.2. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 209
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 215
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.
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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)
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].
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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.
4. IANA Considerations
To be determined.
5. Notations 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].
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".
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o The "EBMLMaxSizeLength" of the "EBML Header" MUST be between "1"
and "8" inclusive.
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 Lanaguage 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
Size = 1 + (1-8) + 4 + (4 + (4)) octets. So from 6 to 21 octets.
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 timecodes MAY NOT be consecutive. But a frame
with a past timecode 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 timecode. It is used with different parts of a frame with
different priorities.
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6.2.3.1. Block Header
+--------+--------+-------------------------------------------------+
| Offset | Player | Description |
+--------+--------+-------------------------------------------------+
| 0x00+ | MUST | Track Number (Track Entry). It is coded in EBML |
| | | like form (1 octet if the value is < 0x80, 2 if |
| | | < 0x4000, etc) (most significant bits set to |
| | | increase the range). |
| 0x01+ | MUST | Timecode (relative to Cluster timecode, 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 |
+--------+-----+--------+-------------------------------------------+
6.2.3.3. 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 |
+--------+--------+--------------------------+
6.2.4. Lacing
Lacing is a mechanism to save space when storing data. It is
typically used for small blocks of data (refered to as frames in
matroska). There are 3 types of lacing : the Xiph one inspired by
what is found in the Ogg container, the EBML one which is the same
with sizes coded differently and the fixed-size one where the size is
not coded. As an example is better than words...
Let's say you want 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, you can store them in
a lace to save space. They will then be solved in the same block as
follows:
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 :
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+----------------------------------+--------------------------------+
| Bit Representation | Value |
+----------------------------------+--------------------------------+
| 1xxx xxxx | value -(2^6-1) to 2^6-1 (ie 0 |
| | to 2^7-2 minus 2^6-1, half of |
| | the range) |
| 01xx xxxx xxxx xxxx | value -(2^13-1) to 2^13-1 |
| 001x xxxx xxxx xxxx xxxx 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)
o Lacing head: Number of frames in the lace -1, i.e. 2 (the 800 and
400 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
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o Data in frame 3
6.2.4.4. SimpleBlock Structure
The SimpleBlock is very inspired by the [Block
structure](({{site.baseurl}}/index.html#block-structure). The main
differences are the added Keyframe flag and Discardable flag.
Otherwise everything is the same.
Size = 1 + (1-8) + 4 + (4 + (4)) octets. So from 6 to 21 octets.
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 timecodes MAY NOT be consecutive. But a frame
with a past timecode 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 timecode. It is used with different parts of a frame with
different priorities.
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 | Timecode (relative to Cluster timecode, signed |
| | | int16) |
+--------+--------+-------------------------------------------------+
6.2.4.4.2. SimpleBlock Header Flags
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+--------+-----+--------+-------------------------------------------+
| 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
+--------+--------+--------------------------+
| Offset | Player | Description |
+--------+--------+--------------------------+
| 0x00 | MUST | Consecutive laced frames |
+--------+--------+--------------------------+
7. Matroska Structure
A Matroska file is composed of one or many "EBML Documents" that use
the "Matroska Document Type". Each "EBML Document" MUST start with
an "EBML Header" and then the "Root Element", which is called
"Segment" in Matroska. Matroska defines several "Top Level Elements"
which MAY occur within the "Segment".
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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.
+-------------+
| EBML Header |
+---------------------------+
| Segment | SeekHead |
| |-------------|
| | Info |
| |-------------|
| | Tracks |
| |-------------|
| | Chapters |
| |-------------|
| | Cluster |
| |-------------|
| | Cues |
| |-------------|
| | Attachments |
| |-------------|
| | Tags |
+---------------------------+
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7.1. Matroska Top Level Elements
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 where other "Top Level Elements" of the "Segment" are located in
order to let the parser know where the other major parts of the file
are. This element isn't technicaly REQUIRED, but 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 because Matroska
has flexible ordering requirements; for instance, the "Chapters
Element" could 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 so that the file can be
identified around the world, and if it is part of a series of
"Segments", the unique identifier(s) of any linked "Segments".
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+-------------------------+
| Info | SegmentUID |
| |------------------|
| | SegmentFilename |
| |------------------|
| | PrevUID |
| |------------------|
| | PrevFilename |
| |------------------|
| | NextUID |
| |------------------|
| | NextFilename |
| |------------------|
| | SegmentFamily |
| |------------------|
| | ChapterTranslate |
| |------------------|
| | TimecodeScale |
| |------------------|
| | Duration |
| |------------------|
| | DateUTC |
| |------------------|
| | Title |
| |------------------|
| | MuxingApp |
| |------------------|
| | WritingApp |
|-------------------------|
Representation of a Info Element and its Child Elements.
The "Tracks Elements" tells us the technical details of what is in
each track. For instance, is it a video, audio or subtitle track?
What resolution is the video? What sample rate is the audio? The
"Tracks Elements" can store the name, number, unique identifier,
language, and type (audio, video, subtitles, etc) of each track. The
"Tracks Element" also identifies what codec to use to decode the
track and has the codec's private data for 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" section lists all of the Chapters. Chapters
are a way to set predefined points to jump to in video or audio.
+----------------------------------------------+
| Chapters | EditionEntry | EditionUID |
| | |--------------------|
| | | EditionFlagHidden |
| | |--------------------|
| | | EditionFlagDefault |
| | |--------------------|
| | | EditionFlagOrdered |
| | |----------------------------------------+
| | | ChapterAtom | ChapterUID |
| | | |-------------------|
| | | | ChapterStringUID |
| | | |-------------------|
| | | | ChapterTimeStart |
| | | |-------------------|
| | | | ChapterTimeEnd |
| | | |-------------------|
| | | | ChapterFlagHidden |
| | | |----------------------------------+
| | | | ChapterDisplay | ChapString |
| | | | |--------------|
| | | | | ChapLanguage |
+---------------------------------------------------------------------------------+
Representation of the Chapters Element and a selection of its
Descendant Elements.
The "Cluster Elements" contain all of the video frames and audio for
each track. In a given Matroska file, there are usually many
"Cluster Elements". The Clusters help to break up the "SimpleBlock"
or "BlockGroup Elements" and help with seeking and error protection.
It is RECOMMENDED the size of each individual "Cluster Element" be
limited to store no more than 5 seconds or 5 megabytes. Every
Cluster contains a timecode, usually the timecode that the first
Block in the Cluster SHOULD be played back, but it doesn't have to
be. Then there are one or more (usually many more) "BlockGroups" or
"SimpleBlocks" in each Cluster. A BlockGroup can contain a Block of
data, and any information relating directly to that Block.
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+--------------------------+
| Cluster | Timecode |
| |----------------|
| | SilentTracks |
| |----------------|
| | Position |
| |----------------|
| | PrevSize |
| |----------------|
| | SimpleBlock |
| |----------------|
| | BlockGroup |
| |----------------|
| | EncryptedBlock |
+--------------------------+
Representation of a Cluster Element and its immediate Child Elements.
Below is a representation of the Block structure.
o Portion of Block
* Data Type
+ Bit Flag
o Header
* TrackNumber
* Timecode
* Flags
* Gap
* Lacing
* Reserved
o Optional
* FrameSize
o Data
* Frame
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Although the Timecode value is stored once per Cluster, another
timecode is stored within the Block structure itself. The way this
works is that the Timecode in the Cluster is relative to the entire
"Segment". It is usually the Timecode that the first Block in the
Cluster needs to be played at. The Timecode in the Block itself is
relative to the Timecode in the Cluster. For example, let's say that
the Timecode in the Cluster is set to 10 seconds, and you have a
Block in that Cluster that is supposed to be played 12 seconds into
the clip; this means that the Timecode 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,
we put the timecode of the needed Block. And because you can have as
many "ReferenceBlock Elements" as you want 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 each of the tracks. It is similar to
the "SeekHead Element", but this is used for seeking to a specific
time when playing back the file. Without this it is possible to
seek, but it is much more difficult because the player has to 'hunt
and peck' through the file looking for the correct timecode. "Cues"
contains "CuePoint Elements" which store the timecode ("CueTime") and
then a listing for the exact position in the file for each of the
tracks for that timecode. The "Cues" are pretty flexible for what
exactly you want to index. For instance, you can index every single
timecode of every "Block" or index selectively. If you have a video
file, 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, script writer,
singer, actors, directors, titles, edition, price, dates, genre,
comments, etc. And it allows you to enter many of these (title,
edition, comments, etc.) in different languages.
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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. # 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.
7.2. 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". |
+-----------+----------+--------------------------------------------+
7.3. Matroska Schema
Here the definition of each Matroska Element is provided.
% concatenate with Matroska EBML Schema converted to markdown %
7.3.1. EBMLMaxIDLength Element
name: "EBMLMaxIDLength"
path: "1*1(\EBML\EBMLMaxIDLength)"
id: "0x42F2"
minOccurs: "1"
maxOccurs: "1"
range: "4"
default: "4"
type: "uinteger"
7.3.2. 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"
7.3.3. 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.
7.3.4. 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.
7.3.5. 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.
7.3.6. 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.
7.3.7. 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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7.3.8. Info Element
name: "Info"
path: "1*(\Segment\Info)"
id: "0x1549A966"
minOccurs: "1"
type: "master"
minver: "1"
definition: Contains general information about the Segment.
7.3.9. 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.
7.3.10. 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.
7.3.11. 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.
7.3.12. 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.
7.3.13. 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.
7.3.14. 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.
7.3.15. 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.
7.3.16. 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.
7.3.17. 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.
7.3.18. 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
7.3.19. 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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7.3.20. TimecodeScale Element
name: "TimecodeScale"
path: "1*1(\Segment\Info\TimecodeScale)"
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).
7.3.21. 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
TimecodeScale.
7.3.22. 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.
7.3.23. 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.
7.3.24. 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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7.3.25. 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.
7.3.26. 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.
7.3.27. Timecode Element
name: "Timecode"
path: "1*1(\Segment\Cluster\Timecode)"
id: "0xE7"
minOccurs: "1"
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maxOccurs: "1"
type: "uinteger"
minver: "1"
documentation: Absolute timestamp of the cluster (based on
TimecodeScale).
7.3.28. 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.
7.3.29. 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.
7.3.30. 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.
7.3.31. 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.
7.3.32. 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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7.3.33. 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.
7.3.34. 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 Timecode. (see Block Structure)
7.3.35. 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)
7.3.36. 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.
7.3.37. 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.
7.3.38. 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.
7.3.39. 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).
7.3.40. 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 TimecodeScale).
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. When
set to 0 that means the frame is not a keyframe.
7.3.41. 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.
7.3.42. ReferenceBlock Element
name: "ReferenceBlock"
path: "0*(\Segment\Cluster\BlockGroup\ReferenceBlock)"
id: "0xFB"
type: "integer"
minver: "1"
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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.
7.3.43. 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.
7.3.44. 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.
7.3.45. DiscardPadding Element
name: "DiscardPadding"
path: "0*1(\Segment\Cluster\BlockGroup\DiscardPadding)"
id: "0x75A2"
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maxOccurs: "1"
type: "integer"
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.
7.3.46. Slices Element
name: "Slices"
path: "0*1(\Segment\Cluster\BlockGroup\Slices)"
id: "0x8E"
maxOccurs: "1"
type: "master"
minver: "1"
documentation: Contains slices description.
7.3.47. 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.
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7.3.48. LaceNumber Element
name: "LaceNumber"
path: "0*1(\Segment\Cluster\BlockGroup\Slices\TimeSlice\LaceNumber)"
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.
7.3.49. 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).
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7.3.50. BlockAdditionID Element
name: "BlockAdditionID"
path:
"0*1(\Segment\Cluster\BlockGroup\Slices\TimeSlice\BlockAdditionID)"
id: "0xCB"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "0"
maxver: "0"
documentation: The ID of the BlockAdditional Element (0 is the main
Block).
7.3.51. 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.
7.3.52. SliceDuration Element
name: "SliceDuration"
path:
"0*1(\Segment\Cluster\BlockGroup\Slices\TimeSlice\SliceDuration)"
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id: "0xCF"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "0"
maxver: "0"
documentation: The (scaled) duration to apply to the Element.
7.3.53. 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
7.3.54. ReferenceOffset Element
name: "ReferenceOffset"
path:
"1*1(\Segment\Cluster\BlockGroup\ReferenceFrame\ReferenceOffset)"
id: "0xC9"
minOccurs: "1"
maxOccurs: "1"
type: "uinteger"
minver: "0"
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maxver: "0"
documentation: DivX trick track extensions
7.3.55. ReferenceTimeCode Element
name: "ReferenceTimeCode"
path:
"1*1(\Segment\Cluster\BlockGroup\ReferenceFrame\ReferenceTimeCode)"
id: "0xCA"
minOccurs: "1"
maxOccurs: "1"
type: "uinteger"
minver: "0"
maxver: "0"
documentation: DivX trick track extensions
7.3.56. 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)
7.3.57. Tracks Element
name: "Tracks"
path: "0*(\Segment\Tracks)"
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id: "0x1654AE6B"
type: "master"
minver: "1"
documentation: A Top-Level Element of information with many tracks
described.
7.3.58. TrackEntry Element
name: "TrackEntry"
path: "1*(\Segment\Tracks\TrackEntry)"
id: "0xAE"
minOccurs: "1"
type: "master"
minver: "1"
documentation: Describes a track with all Elements.
7.3.59. 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).
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7.3.60. TrackUID Element
name: "TrackUID"
path: "1*1(\Segment\Tracks\TrackEntry\TrackUID)"
id: "0x73C5"
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.
7.3.61. 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.
7.3.62. FlagEnabled Element
name: "FlagEnabled"
path: "1*1(\Segment\Tracks\TrackEntry\FlagEnabled)"
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id: "0xB9"
minOccurs: "1"
maxOccurs: "1"
range: "0-1"
default: "1"
type: "uinteger"
minver: "2"
documentation: Set if the track is usable. (1 bit)
7.3.63. 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)
7.3.64. FlagForced Element
name: "FlagForced"
path: "1*1(\Segment\Tracks\TrackEntry\FlagForced)"
id: "0x55AA"
minOccurs: "1"
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maxOccurs: "1"
range: "0-1"
default: "0"
type: "uinteger"
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)
7.3.65. 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)
7.3.66. MinCache Element
name: "MinCache"
path: "1*1(\Segment\Tracks\TrackEntry\MinCache)"
id: "0x6DE7"
minOccurs: "1"
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maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "1"
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.
7.3.67. 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.
7.3.68. 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 TimecodeScale)
per frame ('frame' in the Matroska sense -- one Element put into a
(Simple)Block).
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7.3.69. DefaultDecodedFieldDuration Element
name: "DefaultDecodedFieldDuration"
path: "0*1(\Segment\Tracks\TrackEntry\DefaultDecodedFieldDuration)"
id: "0x234E7A"
maxOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "4"
documentation: The period in nanoseconds (not scaled by TimcodeScale)
between two successive fields at the output of the decoding process
(see the notes)
7.3.70. TrackTimecodeScale Element
name: "TrackTimecodeScale"
path: "1*1(\Segment\Tracks\TrackEntry\TrackTimecodeScale)"
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).
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7.3.71. TrackOffset Element
name: "TrackOffset"
path: "0*1(\Segment\Tracks\TrackEntry\TrackOffset)"
id: "0x537F"
maxOccurs: "1"
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.
7.3.72. 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.
7.3.73. Name Element
name: "Name"
path: "0*1(\Segment\Tracks\TrackEntry\Name)"
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id: "0x536E"
maxOccurs: "1"
type: "utf-8"
minver: "1"
documentation: A human-readable track name.
7.3.74. 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.
7.3.75. 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.
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7.3.76. CodecID Element
name: "CodecID"
path: "1*1(\Segment\Tracks\TrackEntry\CodecID)"
id: "0x86"
minOccurs: "1"
maxOccurs: "1"
type: "string"
minver: "1"
documentation: An ID corresponding to the codec, see the codec page
for more info.
7.3.77. 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.
7.3.78. CodecName Element
name: "CodecName"
path: "0*1(\Segment\Tracks\TrackEntry\CodecName)"
id: "0x258688"
maxOccurs: "1"
type: "utf-8"
minver: "1"
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documentation: A human-readable string specifying the codec.
7.3.79. AttachmentLink Element
name: "AttachmentLink"
path: "0*1(\Segment\Tracks\TrackEntry\AttachmentLink)"
id: "0x7446"
maxOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "1"
maxver: "3"
documentation: The UID of an attachment that is used by this codec.
7.3.80. 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.
7.3.81. CodecInfoURL Element
name: "CodecInfoURL"
path: "0*(\Segment\Tracks\TrackEntry\CodecInfoURL)"
id: "0x3B4040"
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type: "string"
minver: "0"
maxver: "0"
documentation: A URL to find information about the codec used.
7.3.82. 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.
7.3.83. 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).
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7.3.84. TrackOverlay Element
name: "TrackOverlay"
path: "0*(\Segment\Tracks\TrackEntry\TrackOverlay)"
id: "0x6FAB"
type: "uinteger"
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.
7.3.85. 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.
7.3.86. SeekPreRoll Element
name: "SeekPreRoll"
path: "1*1(\Segment\Tracks\TrackEntry\SeekPreRoll)"
id: "0x56BB"
minOccurs: "1"
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maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "4"
documentation: After a discontinuity, SeekPreRoll is the duration in
nanoseconds of the data the decoder MUST decode before the decoded
data is valid.
7.3.87. 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.
7.3.88. 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.
7.3.89. TrackTranslateCodec Element
name: "TrackTranslateCodec"
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path:
"1*1(\Segment\Tracks\TrackEntry\TrackTranslate\TrackTranslateCodec)"
id: "0x66BF"
minOccurs: "1"
maxOccurs: "1"
type: "uinteger"
minver: "1"
documentation: The chapter codec.
7.3.90. 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.
7.3.91. Video Element
name: "Video"
path: "0*1(\Segment\Tracks\TrackEntry\Video)"
id: "0xE0"
maxOccurs: "1"
type: "master"
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minver: "1"
documentation: Video settings.
7.3.92. FlagInterlaced Element
name: "FlagInterlaced"
path: "1*1(\Segment\Tracks\TrackEntry\Video\FlagInterlaced)"
id: "0x9A"
minOccurs: "1"
maxOccurs: "1"
range: "0-2"
default: "0"
type: "uinteger"
minver: "2"
documentation: A flag to declare is the video is known to be
progressive or interlaced and if applicable to declare details about
the interlacement.
7.3.93. 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"
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documentation: Declare the field ordering of the video. If
FlagInterlaced is not set to 1, this Element MUST be ignored.
7.3.94. StereoMode Element
name: "StereoMode"
path: "0*1(\Segment\Tracks\TrackEntry\Video\StereoMode)"
id: "0x53B8"
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.
7.3.95. 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.
7.3.96. OldStereoMode Element
name: "OldStereoMode"
path: "0*1(\Segment\Tracks\TrackEntry\Video\OldStereoMode)"
id: "0x53B9"
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maxOccurs: "1"
type: "uinteger"
maxver: "0"
documentation: DEPRECATED, DO NOT USE. Bogus StereoMode value used
in old versions of libmatroska.
7.3.97. PixelWidth Element
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.
7.3.98. 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.
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7.3.99. PixelCropBottom Element
name: "PixelCropBottom"
path: "0*1(\Segment\Tracks\TrackEntry\Video\PixelCropBottom)"
id: "0x54AA"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "1"
documentation: The number of video pixels to remove at the bottom of
the image (for HDTV content).
7.3.100. 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.
7.3.101. PixelCropLeft Element
name: "PixelCropLeft"
path: "0*1(\Segment\Tracks\TrackEntry\Video\PixelCropLeft)"
id: "0x54CC"
maxOccurs: "1"
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default: "0"
type: "uinteger"
minver: "1"
documentation: The number of video pixels to remove on the left of
the image.
7.3.102. PixelCropRight Element
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.
7.3.103. 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"
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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.
7.3.104. DisplayHeight Element
name: "DisplayHeight"
path: "0*1(\Segment\Tracks\TrackEntry\Video\DisplayHeight)"
id: "0x54BA"
maxOccurs: "1"
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.
7.3.105. 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.
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7.3.106. 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.
7.3.107. 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".
7.3.108. GammaValue Element
name: "GammaValue"
path: "0*1(\Segment\Tracks\TrackEntry\Video\GammaValue)"
id: "0x2FB523"
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maxOccurs: "1"
range: "> 0x0p+0"
type: "float"
minver: "0"
maxver: "0"
documentation: Gamma Value.
7.3.109. FrameRate Element
name: "FrameRate"
path: "0*1(\Segment\Tracks\TrackEntry\Video\FrameRate)"
id: "0x2383E3"
maxOccurs: "1"
range: "> 0x0p+0"
type: "float"
minver: "0"
maxver: "0"
documentation: Number of frames per second. Informational only.
7.3.110. 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.
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7.3.111. MatrixCoefficients Element
name: "MatrixCoefficients"
path:
"0*1(\Segment\Tracks\TrackEntry\Video\Colour\MatrixCoefficients)"
id: "0x55B1"
maxOccurs: "1"
default: "2"
type: "uinteger"
minver: "4"
documentation: The Matrix Coefficients of the video used to derive
luma and chroma values from reg, 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.
7.3.112. 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.
7.3.113. ChromaSubsamplingHorz Element
name: "ChromaSubsamplingHorz"
path:
"0*1(\Segment\Tracks\TrackEntry\Video\Colour\ChromaSubsamplingHorz)"
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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.
7.3.114. ChromaSubsamplingVert Element
name: "ChromaSubsamplingVert"
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.
7.3.115. CbSubsamplingHorz Element
name: "CbSubsamplingHorz"
path:
"0*1(\Segment\Tracks\TrackEntry\Video\Colour\CbSubsamplingHorz)"
id: "0x55B5"
maxOccurs: "1"
type: "uinteger"
minver: "4"
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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.
7.3.116. CbSubsamplingVert Element
name: "CbSubsamplingVert"
path:
"0*1(\Segment\Tracks\TrackEntry\Video\Colour\CbSubsamplingVert)"
id: "0x55B6"
maxOccurs: "1"
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.
7.3.117. 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.
7.3.118. ChromaSitingVert Element
name: "ChromaSitingVert"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\ChromaSitingVert)"
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id: "0x55B8"
maxOccurs: "1"
default: "0"
type: "uinteger"
minver: "4"
documentation: How chroma is subsampled vertically.
7.3.119. Range Element
name: "Range"
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.
7.3.120. TransferCharacteristics Element
name: "TransferCharacteristics"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\TransferCharacteri
stics)"
id: "0x55BA"
maxOccurs: "1"
default: "2"
type: "uinteger"
minver: "4"
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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.
7.3.121. Primaries Element
name: "Primaries"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\Primaries)"
id: "0x55BB"
maxOccurs: "1"
default: "2"
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.
7.3.122. 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).
7.3.123. MaxFALL Element
name: "MaxFALL"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\MaxFALL)"
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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).
7.3.124. MasteringMetadata Element
name: "MasteringMetadata"
path:
"0*1(\Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata)"
id: "0x55D0"
maxOccurs: "1"
type: "master"
minver: "4"
documentation: SMPTE 2086 mastering data.
7.3.125. 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.
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7.3.126. 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.
7.3.127. 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.
7.3.128. PrimaryGChromaticityY Element
name: "PrimaryGChromaticityY"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\
PrimaryGChromaticityY)"
id: "0x55D4"
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maxOccurs: "1"
range: "0-1"
type: "float"
minver: "4"
documentation: Green Y chromaticity coordinate as defined by CIE
1931.
7.3.129. PrimaryBChromaticityX Element
name: "PrimaryBChromaticityX"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\
PrimaryBChromaticityX)"
id: "0x55D5"
maxOccurs: "1"
range: "0-1"
type: "float"
minver: "4"
documentation: Blue X chromaticity coordinate as defined by CIE 1931.
7.3.130. 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.
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7.3.131. 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.
7.3.132. 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.
7.3.133. LuminanceMax Element
name: "LuminanceMax"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\
LuminanceMax)"
id: "0x55D9"
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maxOccurs: "1"
range: ">= 0x0p+0"
type: "float"
minver: "4"
documentation: Maximum luminance. Represented in candelas per square
meter (cd/m^2).
7.3.134. LuminanceMin Element
name: "LuminanceMin"
path: "0*1(\Segment\Tracks\TrackEntry\Video\Colour\MasteringMetadata\
LuminanceMin)"
id: "0x55DA"
maxOccurs: "1"
range: ">= 0x0p+0"
type: "float"
minver: "4"
documentation: Mininum luminance. Represented in candelas per square
meter (cd/m^2).
7.3.135. 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.
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7.3.136. 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"
documentation: Describes the projection used for this video track.
7.3.137. 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
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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.
7.3.138. ProjectionPoseYaw Element
name: "ProjectionPoseYaw"
path:
"1*1(\Segment\Tracks\TrackEntry\Video\Projection\ProjectionPoseYaw)"
id: "0x7673"
minOccurs: "1"
maxOccurs: "1"
default: "0x0p+0"
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.
7.3.139. 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"
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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.
7.3.140. ProjectionPoseRoll Element
name: "ProjectionPoseRoll"
path:
"1*1(\Segment\Tracks\TrackEntry\Video\Projection\ProjectionPoseRoll)"
id: "0x7675"
minOccurs: "1"
maxOccurs: "1"
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.
7.3.141. Audio Element
name: "Audio"
path: "0*1(\Segment\Tracks\TrackEntry\Audio)"
id: "0xE1"
maxOccurs: "1"
type: "master"
minver: "1"
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documentation: Audio settings.
7.3.142. 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"
documentation: Sampling frequency in Hz.
7.3.143. 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).
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7.3.144. 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.
7.3.145. ChannelPositions Element
name: "ChannelPositions"
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.
7.3.146. BitDepth Element
name: "BitDepth"
path: "0*1(\Segment\Tracks\TrackEntry\Audio\BitDepth)"
id: "0x6264"
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maxOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "1"
documentation: Bits per sample, mostly used for PCM.
7.3.147. TrackOperation Element
name: "TrackOperation"
path: "0*1(\Segment\Tracks\TrackEntry\TrackOperation)"
id: "0xE2"
maxOccurs: "1"
type: "master"
minver: "3"
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.
7.3.148. 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
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7.3.149. 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
7.3.150. TrackPlaneUID Element
name: "TrackPlaneUID"
path: "1*1(\Segment\Tracks\TrackEntry\TrackOperation\TrackCombinePlan
es\TrackPlane\TrackPlaneUID)"
id: "0xE5"
minOccurs: "1"
maxOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "3"
documentation: The trackUID number of the track representing the
plane.
7.3.151. TrackPlaneType Element
name: "TrackPlaneType"
path: "1*1(\Segment\Tracks\TrackEntry\TrackOperation\TrackCombinePlan
es\TrackPlane\TrackPlaneType)"
id: "0xE6"
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minOccurs: "1"
maxOccurs: "1"
type: "uinteger"
minver: "3"
documentation: The kind of plane this track corresponds to.
7.3.152. TrackJoinBlocks Element
name: "TrackJoinBlocks"
path:
"0*1(\Segment\Tracks\TrackEntry\TrackOperation\TrackJoinBlocks)"
id: "0xE9"
maxOccurs: "1"
type: "master"
minver: "3"
documentation: Contains the list of all tracks whose Blocks need to
be combined to create this virtual track
7.3.153. 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.
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7.3.154. 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
7.3.155. TrickTrackSegmentUID Element
name: "TrickTrackSegmentUID"
path: "0*1(\Segment\Tracks\TrackEntry\TrickTrackSegmentUID)"
id: "0xC1"
maxOccurs: "1"
size: "16"
type: "binary"
minver: "0"
maxver: "0"
documentation: DivX trick track extensions
7.3.156. TrickTrackFlag Element
name: "TrickTrackFlag"
path: "0*1(\Segment\Tracks\TrackEntry\TrickTrackFlag)"
id: "0xC6"
maxOccurs: "1"
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default: "0"
type: "uinteger"
minver: "0"
maxver: "0"
documentation: DivX trick track extensions
7.3.157. TrickMasterTrackUID Element
name: "TrickMasterTrackUID"
path: "0*1(\Segment\Tracks\TrackEntry\TrickMasterTrackUID)"
id: "0xC7"
maxOccurs: "1"
type: "uinteger"
minver: "0"
maxver: "0"
documentation: DivX trick track extensions
7.3.158. 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
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7.3.159. 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.
7.3.160. ContentEncoding Element
name: "ContentEncoding"
path:
"1*(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncoding)"
id: "0x6240"
minOccurs: "1"
type: "master"
minver: "1"
documentation: Settings for one content encoding like compression or
encryption.
7.3.161. ContentEncodingOrder Element
name: "ContentEncodingOrder"
path: "1*1(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncodin
g\ContentEncodingOrder)"
id: "0x5031"
minOccurs: "1"
maxOccurs: "1"
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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.
7.3.162. ContentEncodingScope Element
name: "ContentEncodingScope"
path: "1*1(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncodin
g\ContentEncodingScope)"
id: "0x5032"
minOccurs: "1"
maxOccurs: "1"
range: "not 0"
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)
7.3.163. ContentEncodingType Element
name: "ContentEncodingType"
path: "1*1(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncodin
g\ContentEncodingType)"
id: "0x5033"
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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
7.3.164. ContentCompression Element
name: "ContentCompression"
path: "0*1(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncodin
g\ContentCompression)"
id: "0x5034"
maxOccurs: "1"
type: "master"
minver: "1"
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.
7.3.165. ContentCompAlgo Element
name: "ContentCompAlgo"
path: "1*1(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncodin
g\ContentCompression\ContentCompAlgo)"
id: "0x4254"
minOccurs: "1"
maxOccurs: "1"
default: "0"
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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
7.3.166. 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.
7.3.167. ContentEncryption Element
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.
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7.3.168. 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
7.3.169. ContentEncKeyID Element
name: "ContentEncKeyID"
path: "0*1(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncodin
g\ContentEncryption\ContentEncKeyID)"
id: "0x47E2"
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.
7.3.170. ContentSignature Element
name: "ContentSignature"
path: "0*1(\Segment\Tracks\TrackEntry\ContentEncodings\ContentEncodin
g\ContentEncryption\ContentSignature)"
id: "0x47E3"
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maxOccurs: "1"
type: "binary"
minver: "1"
documentation: A cryptographic signature of the contents.
7.3.171. 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.
7.3.172. ContentSigAlgo Element
name: "ContentSigAlgo"
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
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7.3.173. 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
7.3.174. Cues Element
name: "Cues"
path: "0*1(\Segment\Cues)"
id: "0x1C53BB6B"
maxOccurs: "1"
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.
7.3.175. CuePoint Element
name: "CuePoint"
path: "1*(\Segment\Cues\CuePoint)"
id: "0xBB"
minOccurs: "1"
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type: "master"
minver: "1"
documentation: Contains all information relative to a seek point in
the Segment.
7.3.176. 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.
7.3.177. CueTrackPositions Element
name: "CueTrackPositions"
path: "1*(\Segment\Cues\CuePoint\CueTrackPositions)"
id: "0xB7"
minOccurs: "1"
type: "master"
minver: "1"
documentation: Contain positions for different tracks corresponding
to the timestamp.
7.3.178. CueTrack Element
name: "CueTrack"
path: "1*1(\Segment\Cues\CuePoint\CueTrackPositions\CueTrack)"
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id: "0xF7"
minOccurs: "1"
maxOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "1"
documentation: The track for which a position is given.
7.3.179. CueClusterPosition Element
name: "CueClusterPosition"
path:
"1*1(\Segment\Cues\CuePoint\CueTrackPositions\CueClusterPosition)"
id: "0xF1"
minOccurs: "1"
maxOccurs: "1"
type: "uinteger"
minver: "1"
documentation: The Segment Position of the Cluster containing the
associated Block.
7.3.180. CueRelativePosition Element
name: "CueRelativePosition"
path:
"0*1(\Segment\Cues\CuePoint\CueTrackPositions\CueRelativePosition)"
id: "0xF0"
maxOccurs: "1"
type: "uinteger"
minver: "4"
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documentation: The relative position of the referenced block inside
the cluster with 0 being the first possible position for an Element
inside that cluster.
7.3.181. 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.
7.3.182. CueBlockNumber Element
name: "CueBlockNumber"
path: "0*1(\Segment\Cues\CuePoint\CueTrackPositions\CueBlockNumber)"
id: "0x5378"
maxOccurs: "1"
range: "not 0"
default: "1"
type: "uinteger"
minver: "1"
documentation: Number of the Block in the specified Cluster.
7.3.183. CueCodecState Element
name: "CueCodecState"
path: "0*1(\Segment\Cues\CuePoint\CueTrackPositions\CueCodecState)"
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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.
7.3.184. CueReference Element
name: "CueReference"
path: "0*(\Segment\Cues\CuePoint\CueTrackPositions\CueReference)"
id: "0xDB"
type: "master"
minver: "2"
documentation: The Clusters containing the referenced Blocks.
7.3.185. CueRefTime Element
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.
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7.3.186. 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.
7.3.187. CueRefNumber Element
name: "CueRefNumber"
path: "0*1(\Segment\Cues\CuePoint\CueTrackPositions\CueReference\CueR
efNumber)"
id: "0x535F"
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.
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7.3.188. 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.
7.3.189. Attachments Element
name: "Attachments"
path: "0*1(\Segment\Attachments)"
id: "0x1941A469"
maxOccurs: "1"
type: "master"
minver: "1"
documentation: Contain attached files.
7.3.190. AttachedFile Element
name: "AttachedFile"
path: "1*(\Segment\Attachments\AttachedFile)"
id: "0x61A7"
minOccurs: "1"
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type: "master"
minver: "1"
documentation: An attached file.
7.3.191. 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.
7.3.192. FileName Element
name: "FileName"
path: "1*1(\Segment\Attachments\AttachedFile\FileName)"
id: "0x466E"
minOccurs: "1"
maxOccurs: "1"
type: "utf-8"
minver: "1"
documentation: Filename of the attached file.
7.3.193. FileMimeType Element
name: "FileMimeType"
path: "1*1(\Segment\Attachments\AttachedFile\FileMimeType)"
id: "0x4660"
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minOccurs: "1"
maxOccurs: "1"
type: "string"
minver: "1"
documentation: MIME type of the file.
7.3.194. 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.
7.3.195. 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.
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7.3.196. 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.
7.3.197. FileUsedStartTime Element
name: "FileUsedStartTime"
path: "0*1(\Segment\Attachments\AttachedFile\FileUsedStartTime)"
id: "0x4661"
maxOccurs: "1"
type: "uinteger"
minver: "0"
maxver: "0"
documentation: DivX font extension
7.3.198. FileUsedEndTime Element
name: "FileUsedEndTime"
path: "0*1(\Segment\Attachments\AttachedFile\FileUsedEndTime)"
id: "0x4662"
maxOccurs: "1"
type: "uinteger"
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minver: "0"
maxver: "0"
documentation: DivX font extension
7.3.199. 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.
7.3.200. 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.
7.3.201. EditionUID Element
name: "EditionUID"
path: "0*1(\Segment\Chapters\EditionEntry\EditionUID)"
id: "0x45BC"
maxOccurs: "1"
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range: "not 0"
type: "uinteger"
minver: "1"
documentation: A unique ID to identify the edition. It's useful for
tagging an edition.
7.3.202. EditionFlagHidden Element
name: "EditionFlagHidden"
path: "1*1(\Segment\Chapters\EditionEntry\EditionFlagHidden)"
id: "0x45BD"
minOccurs: "1"
maxOccurs: "1"
range: "0-1"
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)
7.3.203. EditionFlagDefault Element
name: "EditionFlagDefault"
path: "1*1(\Segment\Chapters\EditionEntry\EditionFlagDefault)"
id: "0x45DB"
minOccurs: "1"
maxOccurs: "1"
range: "0-1"
default: "0"
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type: "uinteger"
minver: "1"
documentation: If a flag is set (1) the edition SHOULD be used as the
default one. (1 bit)
7.3.204. EditionFlagOrdered Element
name: "EditionFlagOrdered"
path: "0*1(\Segment\Chapters\EditionEntry\EditionFlagOrdered)"
id: "0x45DD"
maxOccurs: "1"
range: "0-1"
default: "0"
type: "uinteger"
minver: "1"
documentation: Specify if the chapters can be defined multiple times
and the order to play them is enforced. (1 bit)
7.3.205. 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).
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7.3.206. 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.
7.3.207. ChapterStringUID Element
name: "ChapterStringUID"
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.
7.3.208. ChapterTimeStart Element
name: "ChapterTimeStart"
path:
"1*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterTimeStart)"
id: "0x91"
minOccurs: "1"
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maxOccurs: "1"
type: "uinteger"
minver: "1"
documentation: Timestamp of the start of Chapter (not scaled).
7.3.209. ChapterTimeEnd Element
name: "ChapterTimeEnd"
path:
"0*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterTimeEnd)"
id: "0x92"
maxOccurs: "1"
type: "uinteger"
minver: "1"
documentation: Timestamp of the end of Chapter (timestamp excluded,
not scaled).
7.3.210. 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"
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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)
7.3.211. 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"
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)
7.3.212. ChapterSegmentUID Element
name: "ChapterSegmentUID"
path:
"0*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterSegmentUID)"
id: "0x6E67"
maxOccurs: "1"
range: ">0"
size: "16"
type: "binary"
minver: "1"
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documentation: The SegmentUID of another Segment to play during this
chapter.
usage notes: ChapterSegmentUID is mandatory if
ChapterSegmentEditionUID is used.
7.3.213. ChapterSegmentEditionUID Element
name: "ChapterSegmentEditionUID"
path: "0*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterSegmentE
ditionUID)"
id: "0x6EBC"
maxOccurs: "1"
range: "not 0"
type: "uinteger"
minver: "1"
documentation: The EditionUID to play from the Segment linked in
ChapterSegmentUID. If ChapterSegmentEditionUID is undeclared then no
Edition of the linked Segment is used.
7.3.214. 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.
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7.3.215. 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
7.3.216. ChapterTrackNumber Element
name: "ChapterTrackNumber"
path: "1*(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterTrack\Cha
pterTrackNumber)"
id: "0x89"
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.
7.3.217. ChapterDisplay Element
name: "ChapterDisplay"
path: "0*(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterDisplay)"
id: "0x80"
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type: "master"
minver: "1"
documentation: Contains all possible strings to use for the chapter
display.
7.3.218. 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.
7.3.219. 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.
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7.3.220. 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.
7.3.221. ChapCountry Element
name: "ChapCountry"
path: "0*(\Segment\Chapters\EditionEntry\ChapterAtom\ChapterDisplay\C
hapCountry)"
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.
7.3.222. ChapProcess Element
name: "ChapProcess"
path: "0*(\Segment\Chapters\EditionEntry\ChapterAtom\ChapProcess)"
id: "0x6944"
type: "master"
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minver: "1"
documentation: Contains all the commands associated to the Atom.
7.3.223. 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.
7.3.224. 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.
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7.3.225. 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.
7.3.226. ChapProcessTime Element
name: "ChapProcessTime"
path: "1*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapProcess\Cha
pProcessCommand\ChapProcessTime)"
id: "0x6922"
minOccurs: "1"
maxOccurs: "1"
type: "uinteger"
minver: "1"
documentation: Defines when the process command SHOULD be handled
7.3.227. ChapProcessData Element
name: "ChapProcessData"
path: "1*1(\Segment\Chapters\EditionEntry\ChapterAtom\ChapProcess\Cha
pProcessCommand\ChapProcessData)"
id: "0x6933"
minOccurs: "1"
maxOccurs: "1"
type: "binary"
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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.
7.3.228. 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.
7.3.229. Tag Element
name: "Tag"
path: "1*(\Segment\Tags\Tag)"
id: "0x7373"
minOccurs: "1"
type: "master"
minver: "1"
documentation: A single metadata descriptor.
7.3.230. Targets Element
name: "Targets"
path: "1*1(\Segment\Tags\Tag\Targets)"
id: "0x63C0"
minOccurs: "1"
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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.
7.3.231. 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.
7.3.232. 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).
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7.3.233. 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.
7.3.234. TagEditionUID Element
name: "TagEditionUID"
path: "0*(\Segment\Tags\Tag\Targets\TagEditionUID)"
id: "0x63C9"
default: "0"
type: "uinteger"
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.
7.3.235. TagChapterUID Element
name: "TagChapterUID"
path: "0*(\Segment\Tags\Tag\Targets\TagChapterUID)"
id: "0x63C4"
default: "0"
type: "uinteger"
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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.
7.3.236. 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.
7.3.237. SimpleTag Element
name: "SimpleTag"
path: "1*(\Segment\Tags\Tag(1*(\SimpleTag)))"
id: "0x67C8"
minOccurs: "1"
type: "master"
recursive: "1"
minver: "1"
documentation: Contains general information about the target.
7.3.238. TagName Element
name: "TagName"
path: "1*1(\Segment\Tags\Tag\SimpleTag\TagName)"
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id: "0x45A3"
minOccurs: "1"
maxOccurs: "1"
type: "utf-8"
minver: "1"
documentation: The name of the Tag that is going to be stored.
7.3.239. TagLanguage Element
name: "TagLanguage"
path: "1*1(\Segment\Tags\Tag\SimpleTag\TagLanguage)"
id: "0x447A"
minOccurs: "1"
maxOccurs: "1"
default: "und"
type: "string"
minver: "1"
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.
7.3.240. TagLanguageIETF Element
name: "TagLanguageIETF"
path: "0*1(\Segment\Tags\Tag\SimpleTag\TagLanguageIETF)"
id: "0x447B"
maxOccurs: "1"
type: "string"
minver: "4"
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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.
7.3.241. 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.
7.3.242. TagString Element
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.
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7.3.243. 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.
If you intend to implement a Matroska player, make sure you can
handle all the files in our test suite [17], or at least the features
presented there, not necessarily the same codecs.
8. Beginning of File
An EBML file always starts with 0x1A. The 0x1A makes the DOS command
"type" ends display. That way you can include ASCII text before the
EBML data and it can be displayed. The EBML parser is safe from
false-alarm with these ASCII only codes.
Next the EBML header is stored. This allows the the parser to know
what type of EBML file it is parsing.
9. Block Timecodes
The Block's timecode is signed integer that represents the Raw
Timecode relative to the Cluster's [18] Timecode [19], multiplied by
the TimecodeScale (see the TimecodeScale notes [20]).
The Block's timecode is represented by a 16bit signed integer
(sint16). This means that the Block's timecode has a range of -32768
to +32767 units. When using the default value of TimecodeScale, each
integer represents 1ms. So, the maximum time span of Blocks in a
Cluster using the default TimecodeScale of 1ms is 65536ms.
If a Cluster's [21] Timecode [22] is set to zero, it is possible to
have Blocks with a negative Raw Timecode. Blocks with a negative Raw
Timecode are not valid.
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10. Default decoded field duration
The "DefaultDecodedFieldDuration" Element can signal to the
displaying application how often fields of a video sequence will be
available for displaying. It can be used for both interlaced and
progressive content.
If the video sequence is signaled as interlaced, then the period
between two successive fields at the output of the decoding process
equals DefaultDecodedFieldDuration.
For video sequences signaled as progressive it is twice the value of
DefaultDecodedFieldDuration.
These values are valid at the end of the decoding process before
post-processing like 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")
11. 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 "Language" in the scope of the "Track" element). If the
"Parent Element" is not present or assumed, then the Element cannot
be assumed.
12. DRM
Digital Rights Management. See Encryption [23].
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13. Encryption
Encryption in Matroska is designed in a very generic style that
allows people to implement whatever form of encryption is best for
them. It is easily possible to use the encryption framework in
Matroska as a type of DRM.
Because the encryption occurs within the Block, 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 ever decrypting them. This
means that the data is more useful, without having to expose it, or
go through the intensive process of decrypting.
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" Master-
element under the "ContentEncryption" Element.
14. Image cropping
Thanks to the PixelCropXXX elements, it's possible to crop the image
before being resized. That means the image size follows this path:
PixelXXX (size of the coded image) -> PixelCropXXX (size of the image
to keep) -> DisplayXXX (resized cropped image)
15. Matroska version indicators
The EBML Header each Matroska file starts with contains two version
number fields that inform a reading application about what to expect.
These are "DocTypeVersion" and "DocTypeReadVersion".
"DocTypeVersion" MUST contain 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" of at least 2
while a file containing "CueRelativePosition" Elements MUST have a
"DocTypeVersion" of at least 4.
The "DocTypeReadVersion" MUST contain the minimum version number a
reading application MUST at least support properly 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
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evaluating "CueRelativePosition" is not REQUIRED for standard
playback -- it only 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 Unknown Elements [24].
16. Mime Types
There is no IETF endorsed MIME type for Matroska files. But you can
use the ones we have defined on our web server:
o .mka : Matroska audio "audio/x-matroska"
o .mkv : Matroska video "video/x-matroska"
o .mk3d : Matroska 3D video "video/x-matroska-3d"
17. Octet
An Octet refers to a byte made of 8 bits.
18. Overlay Track
Overlay tracks SHOULD be rendered in the same 'channel' as the track
it's linked to. When content is found in such a track it is played
on the rendering channel instead of the original track.
19. 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".
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19.1. Segment Position Exception
"Elements" that are defined to store a "Segment Position" MAY define
reserved values to indicate a special meaning.
19.2. 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.
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".
20. Raw Timecode
The exact time of an object represented in nanoseconds. To find out
a Block's Raw Timecode, you need the Block's timecode, the Cluster's
[25] Timecode [26], and the TimecodeScale. For calculation, please
see the see the TimecodeScale notes.
21. Linked Segments
Matroska provides several methods to link two or many Segments
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, Soft Linking, or Medium 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".
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21.1. Hard Linking
Hard Linking (also called splitting) is the process of creating a
Linked Segment by relating multiple Segments 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 MAY be Hard Linked as a Linked Segment
through cross-referencing each other with "SegmentUID", "PrevUID",
and "NextUID" as in this table.
+--------+------------------+-------------------+-------------------+
| 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" | | |
+--------+------------------+-------------------+-------------------+
21.2. 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 Element, so that
the player can quickly switch from one to the other.
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21.3. Medium Linking
Medium Linking creates relationships between Segments using Ordered
Chapters and the "ChapterSegmentUID" Element. A Segment Edition with
Ordered Chapters MAY contain Chapters 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 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.
22. Timecode Types
o Absolute Timecode = Block+Cluster
o Relative Timecode = Block
o Scaled Timecode = Block+Cluster
o Raw Timecode = (Block+Cluster)_TimecodeScale_TrackTimecodeScale
23. TimecodeScale
The TimecodeScale [27] is used to calculate the Raw Timecode of a
Block. The timecode is obtained by adding the Block's timecode to
the Cluster's [28] Timecode [29], and then multiplying that result by
the TimecodeScale. The result will be the Block's Raw Timecode in
nanoseconds. The formula for this would look like:
(a + b) * c
a = [Block's Timecode]({{site.baseurl}}/index.html#block-header)
b = [Cluster's](#cluster) [Timecode](#timecode)
c = [TimeCodeScale]({{site.baseurl}}/index.html#TimeCodeScale)
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An example of this is, assume a Cluster's [30] Timecode [31] has a
value of 564264, the Block has a Timecode of 1233, and the
timecodescale 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.
24. TimecodeScale Rounding
Because the default value of TimecodeScale is 1000000, which makes
each integer in the Cluster and Block timecodes equal 1ms, this is
the most commonly used. When dealing with audio, this causes
inaccuracy with where you are seeking to. 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, you want to be able to seek to the exact sample that a song
begins at. If you seek a few sample ahead or behind then 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.
It is usually true that when storing timecodes for an audio stream,
the TimecodeScale MUST have an accuracy of at least that of the audio
samplerate, otherwise there are rounding errors that prevent you from
knowing the precise location of a sample. Here's how a program has
to round each timecode 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 TimecodeScale MUST have at 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 TimecodeScale. The application could even use
some lower value like 22674 which would allow it to be a little bit
imprecise about the original timecodes. But more about that in a
minute.
Next the application wants to write sample number 52340 and
calculates the timecode. This is easy. In order to calculate the
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Raw Timecode in ns all it has to do is calculate "RawTimecode =
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 TimecodeScale 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 "RawTimecode =
round(1000000000 * 52340 / 44100) = round(1186848072.56236) =
1186848073".
The next step is to calculate the Absolute Timecode - that is the
timecode that will be stored in the Matroska file. Here the
application has to divide the Raw Timecode from the previous
paragraph by the TimecodeScale factor and round the result:
"AbsoluteTimecode = round(RawTimecode / TimecodeScale_facotr)" which
will result in the following for our example: "AbsoluteTimecode =
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 TimecodeScale factor 22675 and the audio sample
rate 44100. Later it finds a data block with the Absolute Timecode
of 52342. But how does it get the sample number from these numbers?
First it has to calculate the Raw Timecode of the block it has just
read. Here's no rounding involved, just an integer multiplication:
"RawTimecode = AbsoluteTimecode * TimecodeScale_factor". In our
example: "RawTimecode = 52342 * 22675 = 1186854850".
The conversion from the RawTimecode to the sample number again
requires rounding: "sample_number = round(RawTimecode * 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.
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 timecode in the Matroska file
that does not correspond to the sample number that it started
with. Using a slightly lower timecode scale factor can help here
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in that it removes the need for proper rounding in the conversion
from sample number to Raw Timecode.
25. Track Flags
25.1. Default flag
The "default track" flag is a hint for the playback application 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 she
hasn't chosen a specific track then the 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.
25.2. Forced flag
The "forced" flag tells the playback application 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 player SHOULD determined 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).
26. TrackTimecodeScale
The TrackTimecodeScale [32] 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.
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This is the type of problem that TrackTimecodeScale 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 TrackTimecodeScale. The video will also
be aligned to the NTSC track with the default value of 1.0.
The TrackTimecodeScale 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
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) = ~ 1.04166666666666666667
When writing a file that uses a non-default TrackTimecodeScale, the
values of the Block's timecode are whatever they would be when
normally storing the track with a default value for the
TrackTimecodeScale. However, the data is interleaved a little
differently. Data SHOULD be interleaved by its Raw Timecode [33] in
the order handed back from the encoder. The Raw Timecode of a Block
from a track using TrackTimecodeScale is calculated using:
"(Block's Timecode + Cluster's Timecode) * TimecodeScale *
TrackTimecodeScale"
So, a Block from the PAL track above that had a Scaled Timecode [34]
of 100 seconds would have a Raw Timecode of 104.66666667 seconds, and
so would be stored in that part of the file.
When playing back a track using the TrackTimecodeScale, 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 timecodes from the PAL Audio track are scaled using the
TrackTimecodeScale, resulting in the video playing back in synch with
the audio.
It would be possible for a player to also adjust the audio's
samplerate at the same time as adjusting the timecodes 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,
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for playback, the selected track(s) timecodes 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.
27. Unknown elements
Matroska is based upon the principal 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
[35] 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 signalling that a reading application MUST only support
a lower version number properly in order to play it back (possibly
with a reduced feature set). This implies that 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 which it does not know about
if that unknown element fits into the size constraints set by the
current parent element.
28. Multi-planar and 3D videos
There are 2 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 [36] 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/Height 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 2 frames together in a Block using lacing. The first frame
is the left eye and the other frame is the right eye (or vice versa).
The frames SHOULD be decoded in that order and are possibly dependent
on each other (P and B frames).
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For separate tracks, Matroska needs to define exactly which track
does what. TrackOperation [37] with TrackCombinePlanes [38] do that.
For more details look at how TrackOperation works [39].
The 3D support is still in infancy and may evolve to support more
features.
The StereoMode [40] 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. Readers may support these legacy files by checking
Matroska v2 or 0x53B9. The olders values were 0: mono, 1: right eye,
2: left eye, 3: both eyes.
29. Track Operation
TrackOperation [41] allows combining multiple tracks to make a
virtual one. It uses 2 separate system to combine tracks. One to
create a 3D "composition" (left/right/background planes) and one to
simplify join 2 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 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 Blocks (from BlockGroup and
SimpleBlock) of all the tracks SHOULD be used as if they were defined
for this new virtual Track. When 2 Blocks have overlapping start or
end timecodes, it's up to the underlying system to either drop some
of these frames or render them the way they overlap. In the end this
situation SHOULD be avoided when creating such tracks as you can
never be sure of the end result on different platforms.
30. Matroska Element Ordering Guidelines
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.
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30.1. Top-Level Elements
A valid Matroska file requires only one Top-Level Element, the "Info"
Element; however, to be playable Matroska MUST also contain at least
one "Tracks" and "Cluster" Element. The first "Info" Element and the
first "Tracks" Element MUST either be stored before the first
"Cluster" Element or both be referenced by a "SeekHead" Element which
occurs before the first "Cluster" Element.
After a Matroska file has been created it could still be edited. 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.
30.2. 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.
30.3. 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" MUST reference the identity
and position of the second "SeekHead", the second "SeekHead" MUST
only reference "Cluster" Elements and not any other Top-Level Element
already contained within the first "SeekHead", and the second
"SeekHead" 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"
itself.
It is RECOMMENDED that the first "SeekHead" Element be followed by
some padding (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.
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30.4. Cues (index)
The "Cues Element" is RECOMMENDED to optimize seeking access in
Matroska. It is programmatically simpler to add the "Cues Element"
after all of the "Cluster Elements" are written because this does not
require a prediction of how much space to reserve before writing the
"Cluster Elements". On the other hand, 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".
30.5. Info
The first "Info" Element SHOULD occur before the first "Tracks" and
first "Cluster" Element.
30.6. Chapters
The "Chapters" Element SHOULD be placed before the "Cluster"
Element(s). The "Chapters" Element can be used during playback even
if the user doesn't need to seek. It immediately gives the user
information of 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 starting playing anything.
The "Chapters" Element SHOULD be placed before the first "Tracks"
Element and after the first "Info" Element.
30.7. Attachments
The "Attachments" Element is not meant to use by default when playing
the file, but could contain the cover art and/or fonts. Cover art is
useful even before the file is played and fonts could be needed
before playback starts for initialization of subtitles that could use
them. 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.
30.8. Tags
The "Tags" Element is the one that is most subject to changes after
the file was originally created. So 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(s) are found
early in the stream. When editing the "Tags" Element(s), the
original "Tags" Element at the beginning can be voided [42] and a new
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one written right at the end [43] of the "Segment" Element. The file
size will only marginally change.
30.9. Optimum layout from a muxer
o SeekHead
o Info
o Tracks
o Chapters
o Attachments
o Tags
o Clusters
o Cues
30.10. Optimum layout after editing tags
o SeekHead
o Info
o Tracks
o Chapters
o Attachments
o Void
o Clusters
o Cues
o Tags
30.11. Optimum layout with Cues at the front
o SeekHead
o Info
o Tracks
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o Chapters
o Attachments
o Tags
o Cues
o Clusters
30.12. Cluster Timecode
As each "BlockGroup" and "SimpleBlock" of a "Cluster" Element needs
the Cluster "Timecode", the "Timecode" Element MUST occur as the
first Child Element within the "Cluster" Element.
31. Codec Mappings
A "Codec Mapping" is a set of attributes to identify, name, and
contextualise the format and characteristics of encoded data that can
be contained within Matroska Clusters.
Each TrackEntry used within Matroska MUST reference a defined "Codec
Mapping" using the "Codec ID" to identify and describe the format of
the encoded data in its associated Clusters. This "Codec ID" is a
unique registered identifier that represents the encoding stored
within the Track. Certain encodings MAY also require some form of
codec initialisation in order to provide its decoder with context and
technical metadata.
The intention behind this list is not to list all existing audio and
video codecs, but rather to list those codecs that are currently
supported in Matroska and therefore need a well defined "Codec ID" so
that all developers supporting Matroska will use the same "Codec ID".
If you feel we missed support for a very important codec, please tell
us on our development mailing list (cellar at ietf.org).
31.1. Defining Matroska Codec Support
Support for a codec is defined in Matroska with the following values.
31.1.1. Codec ID
Each codec supported for storage in Matroska MUST have a unique
"Codec ID". Each "Codec ID" MUST be prefixed with the string from
the following table according to the associated type of the codec.
All characters of a "Codec ID Prefix" MUST be capital letters (A-Z)
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except for the last character of a "Codec ID Prefix" which MUST be an
underscore ("_").
Codec Type | Codec ID Prefix Video | "V_" Audio | "A_" Subtitle |
"S_" Button | "B_"
Each "Codec ID" MUST include a "Major Codec ID" immediately following
the "Codec ID Prefix". A "Major Codec ID" MAY be followed by an
OPTIONAL "Codec ID Suffix" to communicate a refinement of the "Major
Codec ID". If a "Codec ID Suffix" is used, then the "Codec ID" MUST
include a forward slash ("/") as a separator between the "Major Codec
ID" and the "Codec ID Suffix". The "Major Codec ID" MUST be composed
of only capital letters (A-Z) and numbers (0-9). The "Codec ID
Suffix" MUST be composed of only capital letters (A-Z), numbers
(0-9), underscore ("_"), and forward slash ("/").
The following table provides examples of valid "Codec IDs" and their
components:
Codec ID Prefix | Major Codec ID | Separator | Codec ID Suffix |
Codec ID A_ | AAC | / | MPEG2/LC/SBR | A_AAC/MPEG2/LC/SBR V_ |
MPEG4 | / | ISO/ASP | V_MPEG4/ISO/ASP V_ | MPEG1 | | | V_MPEG1
31.1.2. Codec Name
Each encoding supported for storage in Matroska MUST have a Codec
Name. The Codec Name provides a readable label for the encoding.
31.1.3. Description
An optional description for the encoding. This value is only
intended for human consumption.
31.1.4. Initialisation
Each encoding supported for storage in Matroska MUST have a defined
Initialisation. The Initialisation MUST describe the storage of data
necessary to initialise the decoder, which MUST be stored within the
"CodecPrivate Element". When the Initialisation is updated within a
track then that updated Initialisation data MUST be written into the
"CodecState Element" of the first "Cluster" to require it. If the
encoding does not require any form of Initialisation then "none" MUST
be used to define the Initialisation and the "CodecPrivate Element"
SHOULD NOT be written and MUST be ignored. Data that is defined
Initialisation to be stored in the "CodecPrivate Element" is known as
"Private Data".
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31.1.5. Citation
Documentation of the associated normative and informative references
for the codec is RECOMMENDED.
31.1.6. Deprecation Date
A timestamp, expressed in [RFC3339] that notes when support for the
"Codec Mapping" within Matroska was deprecated. If a "Codec Mapping"
is defined with a "Deprecation Date", then it is RECOMMENDED that
Matroska writers SHOULD NOT use the "Codec Mapping" after the
"Deprecation Date".
31.1.7. Superseded By
A "Codec Mapping" MAY only be defined with a "Superseded By" value,
if it has an expressed "Deprecation Date". If used, the "Superseded
By" value MUST store the "Codec ID" of another "Codec Mapping" that
has superseded the "Codec Mapping".
31.2. Video Codec Mappings
31.2.1. V_MS/VFW/FOURCC
Codec ID: "V_MS/VFW/FOURCC"
Codec Name: Microsoft (TM) Video Codec Manager (VCM)
Description: The private data contains the VCM structure
BITMAPINFOHEADER including the extra private bytes, as defined by
Microsoft [44]. The data are stored in little endian format (like on
IA32 machines). Where is the Huffman table stored in HuffYUV, not
AVISTREAMINFO ??? And the FourCC, not in AVISTREAMINFO.fccHandler ???
Initialisation: "Private Data" contains the VCM structure
BITMAPINFOHEADER including the extra private bytes, as defined by
Microsoft in <https://msdn.microsoft.com/en-
us/library/windows/desktop/dd183376(v=vs.85).aspx>.
Citation: <https://msdn.microsoft.com/en-us/library/windows/desktop/
dd183376(v=vs.85).aspx>
31.2.2. V_UNCOMPRESSED
Codec ID: V_UNCOMPRESSED
Codec Name: Video, raw uncompressed video frames
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Description: All details about the used colour specs and bit depth
are to be put/read from the KaxCodecColourSpace elements.
Initialisation: none
31.2.3. V_MPEG4/ISO/SP
Codec ID: V_MPEG4/ISO/SP
Codec Name: MPEG4 ISO simple profile (DivX4)
Description: Stream was created via improved codec API (UCI) or even
transmuxed from AVI (no b-frames in Simple Profile), frame order is
coding order.
Initialisation: none
31.2.4. V_MPEG4/ISO/ASP
Codec ID: V_MPEG4/ISO/ASP
Codec Name: MPEG4 ISO advanced simple profile (DivX5, XviD, FFMPEG)
Description: Stream was created via improved codec API (UCI) or
transmuxed from MP4, not simply transmuxed from AVI. Note there are
differences how b-frames are handled in these native streams, when
being compared to a VfW created stream, as here there are "no" dummy
frames inserted, the frame order is exactly the same as the coding
order, same as in MP4 streams.
Initialisation: none
31.2.5. V_MPEG4/ISO/AP
Codec ID: V_MPEG4/ISO/AP
Codec Name: MPEG4 ISO advanced profile
Description: Stream was created via improved codec API (UCI) or
transmuxed from MP4, not simply transmuxed from AVI. Note there are
differences how b-frames are handled in these native streams, when
being compared to a VfW created stream, as here there are "no" dummy
frames inserted, the frame order is exactly the same as the coding
order, same as in MP4 streams.
Initialisation: none
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31.2.6. V_MPEG4/MS/V3
Codec ID: V_MPEG4/MS/V3
Codec Name: Microsoft (TM) MPEG4 V3
Description: Microsoft (TM) MPEG4 V3 and derivates, means DivX3,
Angelpotion, SMR, etc.; stream was created using VfW codec or
transmuxed from AVI; note that V1/V2 are covered in VfW compatibility
mode.
Initialisation: none
31.2.7. V_MPEG1
Codec ID: V_MPEG1
Codec Name: MPEG 1
Description: The Matroska video stream will contain a demuxed
Elementary Stream (ES), where block boundaries are still to be
defined. Its RECOMMENDED to use MPEG2MKV.exe for creating those
files, and to compare the results with self-made implementations
Initialisation: none
31.2.8. V_MPEG2
Codec ID: V_MPEG2
Codec Name: MPEG 2
Description: The Matroska video stream will contain a demuxed
Elementary Stream (ES), where block boundaries are still to be
defined. Its RECOMMENDED to use MPEG2MKV.exe for creating those
files, and to compare the results with self-made implementations
Initialisation: none
31.2.9. V_REAL/RV10
Codec ID: V_REAL/RV10
Codec Name: RealVideo 1.0 aka RealVideo 5
Description: Individual slices from the Real container are combined
into a single frame.
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Initialisation: The "Private Data" contains a "real_video_props_t"
structure in Big Endian byte order as found in librmff [45].
31.2.10. V_REAL/RV20
Codec ID: V_REAL/RV20
Codec Name: RealVideo G2 and RealVideo G2+SVT
Description: Individual slices from the Real container are combined
into a single frame.
Initialisation: The "Private Data" contains a "real_video_props_t"
structure in Big Endian byte order as found in librmff [46].
31.2.11. V_REAL/RV30
Codec ID: V_REAL/RV30
Codec Name: RealVideo 8
Description: Individual slices from the Real container are combined
into a single frame.
Initialisation: The "Private Data" contains a "real_video_props_t"
structure in Big Endian byte order as found in librmff [47].
31.2.12. V_REAL/RV40
Codec ID: V_REAL/RV40
Codec Name: rv40 : RealVideo 9
Description: Individual slices from the Real container are combined
into a single frame.
Initialisation: The "Private Data" contains a "real_video_props_t"
structure in Big Endian byte order as found in librmff [48].
31.2.13. V_QUICKTIME
Codec ID: V_QUICKTIME
Codec Name: Video taken from QuickTime(TM) files
Description: Several codecs as stored in QuickTime, e.g. Sorenson or
Cinepak.
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Initialisation: The "Private Data" contains all additional data that
is stored in the 'stsd' (sample description) atom in the QuickTime
file *after* the mandatory video descriptor structure (starting with
the size and FourCC fields). For an explanation of the QuickTime
file format read QuickTime File Format Specification [49].
31.2.14. V_THEORA
Codec ID: V_THEORA
Codec Name: Theora
Initialisation: The "Private Data" contains the first three Theora
packets in order. The lengths of the packets precedes them. The
actual layout is:
o Byte 1: number of distinct packets '"#p"' minus one inside the
CodecPrivate block. This MUST be '2' for current (as of
2016-07-08) Theora headers.
o Bytes 2..n: lengths of the first '"#p"' packets, coded in Xiph-
style lacing [50]. The length of the last packet is the length of
the CodecPrivate block minus the lengths coded in these bytes
minus one.
o Bytes n+1..: The Theora identification header, followed by the
commend header followed by the codec setup header. Those are
described in the Theora specs [51].
31.2.15. V_PRORES
Codec ID: V_PRORES
Codec Name: Apple ProRes
Initialisation: The "Private Data" contains the fourcc as found in
MP4 movies:
o ap4x: ProRes 4444 XQ
o ap4h: ProRes 4444
o apch: ProRes 422 High Quality
o apcn: ProRes 422 Standard Definition
o apcs: ProRes 422 LT
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o apco: ProRes 422 Proxy
this page for more technical details on ProRes [52]
31.2.16. V_VP8
Codec ID: V_VP8
Codec Name: VP8 Codec format
Description: VP8 is an open and royalty free video compression format
developed by Google and created by On2 Technologies as a successor to
VP7. [RFC6386]
Initialisation: none
31.2.17. V_VP9
Codec ID: V_VP9
Codec Name: VP9 Codec format
Description: VP9 is an open and royalty free video compression format
developed by Google as a successor to VP8. Draft VP9 Bitstream and
Decoding Process Specification [53]
Initialisation: none
31.2.18. V_FFV1
Codec ID: V_FFV1
Codec Name: FF Video Codec 1
Description: FFV1 is a lossless intra-frame video encoding format
designed to efficiently compress video data in a variety of pixel
formats. Compared to uncompressed video, FFV1 offers storage
compression, frame fixity, and self-description, which makes FFV1
useful as a preservation or intermediate video format. Draft FFV1
Specification [54]
Initialisation: For FFV1 versions 0 or 1, "Private Data" SHOULD NOT
be written. For FFV1 version 3 or greater, the "Private Data" MUST
contain the FFV1 Configuration Record structure, as defined in
<https://tools.ietf.org/html/draft-niedermayer-cellar-ffv1-
01#section-4.1>, and no other data.
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31.3. Audio Codec Mappings
31.3.1. A_MPEG/L3
Codec ID: A_MPEG/L3
Codec Name: MPEG Audio 1, 2, 2.5 Layer III
Description: The data contain everything needed for playback in the
MPEG Audio header of each frame. Corresponding ACM wFormatTag :
0x0055
Initialisation: none
31.3.2. A_MPEG/L2
Codec ID: A_MPEG/L2
Codec Name: MPEG Audio 1, 2 Layer II
Description: The data contain everything needed for playback in the
MPEG Audio header of each frame. Corresponding ACM wFormatTag :
0x0050
Initialisation: none
31.3.3. A_MPEG/L1
Codec ID: A_MPEG/L1
Codec Name: MPEG Audio 1, 2 Layer I
Description: The data contain everything needed for playback in the
MPEG Audio header of each frame. Corresponding ACM wFormatTag :
0x0050
Initialisation: none
31.3.4. A_PCM/INT/BIG
Codec ID: A_PCM/INT/BIG
Codec Name: PCM Integer Big Endian
Description: The bitdepth has to be read and set from
KaxAudioBitDepth element. Corresponding ACM wFormatTag : ???
Initialisation: none
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31.3.5. A_PCM/INT/LIT
Codec ID: A_PCM/INT/LIT
Codec Name: PCM Integer Little Endian
Description: The bitdepth has to be read and set from
KaxAudioBitDepth element. Corresponding ACM wFormatTag : 0x0001
Initialisation: none
31.3.6. A_PCM/FLOAT/IEEE
Codec ID: A_PCM/FLOAT/IEEE
Codec Name: Floating Point, IEEE compatible
Description: The bitdepth has to be read and set from
KaxAudioBitDepth element (32 bit in most cases). The float are
stored in little endian order (most common float format).
Corresponding ACM wFormatTag : 0x0003
Initialisation: none
31.3.7. A_MPC
Codec ID: A_MPC
Codec Name: MPC (musepack) SV8
Description: The main developer for musepack has requested that we
wait until the SV8 framing has been fully defined for musepack before
defining how to store it in Matroska.
31.3.8. A_AC3
Codec ID: A_AC3
Codec Name: (Dolby[TM]) AC3
Description: BSID <= 8 !! The private data is void ??? Corresponding
ACM wFormatTag : 0x2000 ; channel number have to be read from the
corresponding audio element
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31.3.9. A_AC3/BSID9
Codec ID: A_AC3/BSID9
Codec Name: (Dolby[TM]) AC3
Description: The ac3 frame header has, similar to the mpeg-audio
header a version field. Normal ac3 is defined as bitstream id 8 (5
Bits, numbers are 0-15). Everything below 8 is still compatible with
all decoders that handle 8 correctly. Everything higher are
additions that break decoder compatibility. For the samplerates
24kHz (00); 22,05kHz (01) and 16kHz (10) the BSID is 9 For the
samplerates 12kHz (00); 11,025kHz (01) and 8kHz (10) the BSID is 10
Initialisation: none
31.3.10. A_AC3/BSID10
Codec ID: A_AC3/BSID10
Codec Name: (Dolby[TM]) AC3
Description: The ac3 frame header has, similar to the mpeg-audio
header a version field. Normal ac3 is defined as bitstream id 8 (5
Bits, numbers are 0-15). Everything below 8 is still compatible with
all decoders that handle 8 correctly. Everything higher are
additions that break decoder compatibility. For the samplerates
24kHz (00); 22,05kHz (01) and 16kHz (10) the BSID is 9 For the
samplerates 12kHz (00); 11,025kHz (01) and 8kHz (10) the BSID is 10
Initialisation: none
31.3.11. A_ALAC
Codec ID: A_ALAC
Codec Name: ALAC (Apple Lossless Audio Codec)
Initialisation: The "Private Data" contains ALAC's magic cookie (both
the codec specific configuration as well as the optional channel
layout information). Its format is described in ALAC's official
source code [55].
31.3.12. A_DTS
Codec ID: A_DTS
Codec Name: Digital Theatre System
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Description: Supports DTS, DTS-ES, DTS-96/26, DTS-HD High Resolution
Audio and DTS-HD Master Audio. The private data is void.
Corresponding ACM wFormatTag : 0x2001
Initialisation: none
31.3.13. A_DTS/EXPRESS
Codec ID: A_DTS/EXPRESS
Codec Name: Digital Theatre System Express
Description: DTS Express (a.k.a. LBR) audio streams. The private
data is void. Corresponding ACM wFormatTag : 0x2001
Initialisation: none
31.3.14. A_DTS/LOSSLESS
Codec ID: A_DTS/LOSSLESS
Codec Name: Digital Theatre System Lossless
Description: DTS Lossless audio that does not have a core substream.
The private data is void. Corresponding ACM wFormatTag : 0x2001
Initialisation: none
31.3.15. A_VORBIS
Codec ID: A_VORBIS
Codec Name: Vorbis
Initialisation: The "Private Data" contains the first three Vorbis
packet in order. The lengths of the packets precedes them. The
actual layout is: - Byte 1: number of distinct packets '"#p"' minus
one inside the CodecPrivate block. This MUST be '2' for current (as
of 2016-07-08) Vorbis headers. - Bytes 2..n: lengths of the first
'"#p"' packets, coded in Xiph-style lacing [56]. The length of the
last packet is the length of the CodecPrivate block minus the lengths
coded in these bytes minus one. - Bytes n+1..: The Vorbis
identification header [57], followed by the Vorbis comment header
[58] followed by the codec setup header [59].
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31.3.16. A_FLAC
Codec ID: A_FLAC
Codec Name: FLAC (Free Lossless Audio Codec) [60]
Initialisation: The "Private Data" contains all the header/metadata
packets before the first data packet. These include the first header
packet containing only the word "fLaC" as well as all metadata
packets.
31.3.17. A_REAL/14_4
Codec ID: A_REAL/14_4
Codec Name: Real Audio 1
Initialisation: The "Private Data" contains either the
"real_audio_v4_props_t" or the "real_audio_v5_props_t" structure
(differentiated by their "version" field; Big Endian byte order) as
found in librmff [61].
31.3.18. A_REAL/28_8
Codec ID: A_REAL/28_8
Codec Name: Real Audio 2
Initialisation: The "Private Data" contains either the
"real_audio_v4_props_t" or the "real_audio_v5_props_t" structure
(differentiated by their "version" field; Big Endian byte order) as
found in librmff [62].
31.3.19. A_REAL/COOK
Codec ID: A_REAL/COOK
Codec Name: Real Audio Cook Codec (codename: Gecko)
Initialisation: The "Private Data" contains either the
"real_audio_v4_props_t" or the "real_audio_v5_props_t" structure
(differentiated by their "version" field; Big Endian byte order) as
found in librmff [63].
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31.3.20. A_REAL/SIPR
Codec ID: A_REAL/SIPR
Codec Name: Sipro Voice Codec
Initialisation: The "Private Data" contains either the
"real_audio_v4_props_t" or the "real_audio_v5_props_t" structure
(differentiated by their "version" field; Big Endian byte order) as
found in librmff [64].
31.3.21. A_REAL/RALF
Codec ID: A_REAL/RALF
Codec Name: Real Audio Lossless Format
Initialisation: The "Private Data" contains either the
"real_audio_v4_props_t" or the "real_audio_v5_props_t" structure
(differentiated by their "version" field; Big Endian byte order) as
found in librmff [65].
31.3.22. A_REAL/ATRC
Codec ID: A_REAL/ATRC
Codec Name: Sony Atrac3 Codec
Initialisation: The "Private Data" contains either the
"real_audio_v4_props_t" or the "real_audio_v5_props_t" structure
(differentiated by their "version" field; Big Endian byte order) as
found in librmff [66].
31.3.23. A_MS/ACM
Codec ID: A_MS/ACM
Codec Name: Microsoft(TM) Audio Codec Manager (ACM)
Description: The data are stored in little endian format (like on
IA32 machines).
Initialisation: The "Private Data" contains the ACM structure
WAVEFORMATEX including the extra private bytes, as defined by
Microsoft [67].
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31.3.24. A_AAC/MPEG2/MAIN
Codec ID: A_AAC/MPEG2/MAIN
Codec Name: MPEG2 Main Profile
Description: Channel number and sample rate have to be read from the
corresponding audio element. Audio stream is stripped from ADTS
headers and normal Matroska frame based muxing scheme is applied.
AAC audio always uses wFormatTag 0xFF.
Initialisation: none
31.3.25. A_AAC/MPEG2/LC
Codec ID: A_AAC/MPEG2/LC
Codec Name: Low Complexity
Description: Channel number and sample rate have to be read from the
corresponding audio element. Audio stream is stripped from ADTS
headers and normal Matroska frame based muxing scheme is applied.
AAC audio always uses wFormatTag 0xFF.
Initialisation: none
31.3.26. A_AAC/MPEG2/LC/SBR
Codec ID: A_AAC/MPEG2/LC/SBR
Codec Name: Low Complexity with Spectral Band Replication
Description: Channel number and sample rate have to be read from the
corresponding audio element. Audio stream is stripped from ADTS
headers and normal Matroska frame based muxing scheme is applied.
AAC audio always uses wFormatTag 0xFF.
Initialisation: none
31.3.27. A_AAC/MPEG2/SSR
Codec ID: A_AAC/MPEG2/SSR
Codec Name: Scalable Sampling Rate
Description: Channel number and sample rate have to be read from the
corresponding audio element. Audio stream is stripped from ADTS
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headers and normal Matroska frame based muxing scheme is applied.
AAC audio always uses wFormatTag 0xFF.
Initialisation: none
31.3.28. A_AAC/MPEG4/MAIN
Codec ID: A_AAC/MPEG4/MAIN
Codec Name: MPEG4 Main Profile
Description: Channel number and sample rate have to be read from the
corresponding audio element. Audio stream is stripped from ADTS
headers and normal Matroska frame based muxing scheme is applied.
AAC audio always uses wFormatTag 0xFF.
Initialisation: none
31.3.29. A_AAC/MPEG4/LC
Codec ID: A_AAC/MPEG4/LC
Codec Name: Low Complexity
Description: Channel number and sample rate have to be read from the
corresponding audio element. Audio stream is stripped from ADTS
headers and normal Matroska frame based muxing scheme is applied.
AAC audio always uses wFormatTag 0xFF.
Initialisation: none
31.3.30. A_AAC/MPEG4/LC/SBR
Codec ID: A_AAC/MPEG4/LC/SBR
Codec Name: Low Complexity with Spectral Band Replication
Description: Channel number and sample rate have to be read from the
corresponding audio element. Audio stream is stripped from ADTS
headers and normal Matroska frame based muxing scheme is applied.
AAC audio always uses wFormatTag 0xFF.
Initialisation: none
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31.3.31. A_AAC/MPEG4/SSR
Codec ID: A_AAC/MPEG4/SSR
Codec Name: Scalable Sampling Rate
Description: Channel number and sample rate have to be read from the
corresponding audio element. Audio stream is stripped from ADTS
headers and normal Matroska frame based muxing scheme is applied.
AAC audio always uses wFormatTag 0xFF.
Initialisation: none
31.3.32. A_AAC/MPEG4/LTP
Codec ID: A_AAC/MPEG4/LTP
Codec Name: Long Term Prediction
Description: Channel number and sample rate have to be read from the
corresponding audio element. Audio stream is stripped from ADTS
headers and normal Matroska frame based muxing scheme is applied.
AAC audio always uses wFormatTag 0xFF.
Initialisation: none
31.3.33. A_QUICKTIME
Codec ID: A_QUICKTIME
Codec Name: Audio taken from QuickTime(TM) files
Description: Several codecs as stored in QuickTime, e.g. QDesign
Music v1 or v2.
Initialisation: The "Private Data" contains all additional data that
is stored in the 'stsd' (sample description) atom in the QuickTime
file *after* the mandatory sound descriptor structure (starting with
the size and FourCC fields). For an explanation of the QuickTime
file format read QuickTime File Format Specification [68].
31.3.34. A_QUICKTIME/QDMC
Codec ID: A_QUICKTIME/QDMC
Codec Name: QDesign Music
Description:
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Initialisation: The "Private Data" contains all additional data that
is stored in the 'stsd' (sample description) atom in the QuickTime
file *after* the mandatory sound descriptor structure (starting with
the size and FourCC fields). For an explanation of the QuickTime
file format read QuickTime File Format Specification [69].
Superseded By: A_QUICKTIME
31.3.35. A_QUICKTIME/QDM2
Codec ID: A_QUICKTIME/QDM2
Codec Name: QDesign Music v2
Description:
Initialisation: The "Private Data" contains all additional data that
is stored in the 'stsd' (sample description) atom in the QuickTime
file *after* the mandatory sound descriptor structure (starting with
the size and FourCC fields). For an explanation of the QuickTime
file format read QuickTime File Format Specification [70].
Superseded By: A_QUICKTIME
31.3.36. A_TTA1
Codec ID: A_TTA1
Codec Name: The True Audio [71] lossless audio compressor
Description: TTA format description [72] Each frame is kept intact,
including the CRC32. The header and seektable are dropped.
SamplingFrequency, Channels and BitDepth are used in the TrackEntry.
wFormatTag = 0x77A1
Initialisation: none
31.3.37. A_WAVPACK4
Codec ID: A_WAVPACK4
Codec Name: WavPack [73] lossless audio compressor
Description: The Wavpack packets consist of a stripped header
followed by the frame data. For multi-track (> 2 tracks) a frame
consists of many packets. For hybrid files (lossy part + correction
part), the correction part is stored in an additional block (level
1). For more details, check the WavPack muxing description [74].
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Initialisation: none
31.4. Subtitle Codec Mappings
31.4.1. S_TEXT/UTF8
Codec ID: S_TEXT/UTF8
Codec Name: UTF-8 Plain Text
Description: Basic text subtitles. For more information, please look
at the Subtitle specifications [75].
31.4.2. S_TEXT/SSA
Codec ID: S_TEXT/SSA
Codec Name: Subtitles Format
Description: The [Script Info] and [V4 Styles] sections are stored in
the codecprivate. Each event is stored in its own Block. For more
information, please read the specs for SSA/ASS [76].
31.4.3. S_TEXT/ASS
Codec ID: S_TEXT/ASS
Codec Name: Advanced Subtitles Format
Description: The [Script Info] and [V4 Styles] sections are stored in
the codecprivate. Each event is stored in its own Block. For more
information, please read the specs for SSA/ASS [77].
31.4.4. S_TEXT/USF
Codec ID: S_TEXT/USF
Codec Name: Universal Subtitle Format
Description: This is mostly defined, but not typed out yet. It will
first be available on the USF specs page [78].
31.4.5. S_TEXT/WEBVTT
Codec ID: S_TEXT/WEBVTT
Codec Name: Web Video Text Tracks Format (WebVTT)
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Description: Advanced text subtitles. For more information about the
storage please look at the WebVTT in Matroska specifications [79].
31.4.6. S_IMAGE/BMP
Codec ID: S_IMAGE/BMP
Codec Name: Bitmap
Description: Basic image based subtitle format; The subtitles are
stored as images, like in the DVD. The timestamp in the block header
of Matroska indicates the start display time, the duration is set
with the Duration element. The full data for the subtitle bitmap is
stored in the Block's data section.
31.4.7. S_DVBSUB
Codec ID: S_DVBSUB
Codec Name: Digital Video Broadcasting (DVB) subtitles
Description: This is the graphical subtitle format used in the
Digital Video Broadcasting standard. For more information about the
storage please look at the Digital Video Broadcasting (DVB) subtitles
in Matroska specifications [80].
31.4.8. S_VOBSUB
Codec ID: S_VOBSUB
Codec Name: VobSub subtitles
Description: The same subtitle format used on DVDs. Supported is
only format version 7 and newer. VobSubs consist of two files, the
.idx containing information, and the .sub, containing the actual
data. The .idx file is stripped of all empty lines, of all comments
and of lines beginning with "alt:" or "langidx:". The line beginning
with "id:" SHOULD be transformed into the appropriate Matroska track
language element and is discarded. All remaining lines but the ones
containing timestamps and file positions are put into the
"CodecPrivate" element.
For each line containing the timestamp and file position data is read
from the appropriate position in the .sub file. This data consists
of a MPEG program stream which in turn contains SPU packets. The
MPEG program stream data is discarded, and each SPU packet is put
into one Matroska frame.
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31.4.9. S_HDMV/PGS
Codec ID: S_HDMV/PGS
Codec Name: HDMV presentation graphics subtitles (PGS)
Description: This is the graphical subtitle format used on Blu-rays.
For more information about the storage please look at the HDMV
presentation graphics subtitles in Matroska specifications [81].
31.4.10. S_HDMV/TEXTST
Codec ID: S_HDMV/TEXTST
Codec Name: HDMV text subtitles
Description: This is the textual subtitle format used on Blu-rays.
For more information about the storage please look at the HDMV text
subtitles in Matroska specifications [82].
31.4.11. S_KATE
Codec ID: S_KATE
Codec Name: Karaoke And Text Encapsulation
Description: A subtitle format developed for ogg. The mapping for
Matroska is described on the Xiph wiki [83]. As for Theora and
Vorbis, Kate headers are stored in the private data as xiph-laced
packets.
31.5. Button Codec Mappings
31.5.1. B_VOBBTN
Codec ID: B_VOBBTN
Codec Name: VobBtn Buttons
Description: Based on MPEG/VOB PCI packets [84]. The file contains a
header consisting of the string "butonDVD" followed by the width and
height in pixels (16 bits integer each) and 4 reserved bytes. The
rest is full PCI packets [85]. #Chapters
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31.6. Edition and Chapter Flags
31.6.1. Chapter Flags
Two "Chapter Flags" are defined to describe the bevahior of the
"ChapterAtom Element": "ChapterFlagHidden" and "ChapterFlagEnabled".
If a "ChapterAtom Element" is a "Child Element" of another
"ChapterAtom Element" which has a "Chapter Flag" set to "true", then
the "Child ChapterAtom Element" MUST be interpretted as having its
same "Chapter Flag" set to "true". If a "ChapterAtom Element" is a
"Child Element" of another "ChapterAtom Element" which has a "Chapter
Flag" set to "false" or the "ChapterAtom Element" does not have a
"ChapterAtom Element" as its "Parent Element", then it MUST be
interpretted 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 interpretted 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 interpretted 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".
31.6.2. Edition Flags
Three "Edition Flags" are defined to describe the bevahior of the
"EditionEntry Element": "EditionFlagHidden", "EditionFlagDefault" and
"EditionFlagOrdered".
The "EditionFlagHidden" Flag behaves similarly to the
"ChapterFlagHidden" Flag: if "EditionFlagHidden" is set to "true"
then its "Child ChapterAtoms Elements" MUST also be interpretted as
if their "ChapterFlagHidden" is also set to "true", regardless of
their own "ChapterFlagHidden" flags. If the "EditionFlagHidden" is
toggled by a "Control Track" to "false" then the "ChapterFlagHidden"
Flags of the "Child ChapterAtoms Elements" SHALL determine if the
"ChapterAtom" is hidden or not.
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31.7. 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).
31.7.1. Matroska Script (0)
This is the case when ChapProcessCodecID [86] = 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 playback SHOULD jump to the Chapter
specified by the UID and play it.
31.7.2. DVD menu (1)
This is the case when ChapProcessCodecID [87] = 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 [88] element found in the Segment Info. This
field uses 2 octets as follows:
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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:
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
[89] 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 preceeding
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)].
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More information on the DVD commands and format on DVD-replica [90],
where we got most of the info about it. You can also get information
on DVD from the DVDinfo project [91].
31.8. 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
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>
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<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>
<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>
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<EditionFlagDefault>0</EditionFlagDefault>
<EditionFlagHidden>0</EditionFlagHidden>
</EditionEntry>
</Chapters>
31.9. Example 2 : nested chapters
In this example an (existing) album is split into different chapters,
and one of them contain another splitting.
31.9.1. 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>
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<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>
<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>
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<ChapLanguage>eng</ChapLanguage>
</ChapterDisplay>
<ChapterFlagHidden>0</ChapterFlagHidden>
<ChapterFlagEnabled>1</ChapterFlagEnabled>
</ChapterAtom>
<ChapterAtom>
<ChapterUID>7</ChapterUID>
<ChapterTimeStart>1180500000</ChapterTimeStart>
<ChapterTimeEnd>1340000000</ChapterTimeEnd>
<ChapterDisplay>
<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>
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</ChapterAtom>
<EditionFlagDefault>0</EditionFlagDefault>
<EditionFlagHidden>0</EditionFlagHidden>
</EditionEntry>
</Chapters>
32. Subtitles
Because Matroska is a general container format, we try to avoid
specifying the formats to store in it. This type of work is really
outside of the scope of a container-only format. However, because
the use of subtitles in A/V containers has been so limited (with the
exception of DVD) we are taking the time to specify how to store some
of the more common subtitle formats in Matroska. This is being done
to help facilitate their growth. Otherwise, incompatibilities could
prevent the standardization and use of subtitle storage.
This page is not meant to be a complete listing of all subtitle
formats that will be used in Matroska, it is only meant to be a guide
for the more common, current formats. It is possible that we will
add future formats to this page as they are created, but it is not
likely as any other new subtitle format designer would likely have
their own specifications. Any specification listed here SHOULD be
strictly adhered to or it SHOULD NOT use the corresponding Codec ID.
Here is a list of pointers for storing subtitles in Matroska:
o Any Matroska file containing only subtitles SHOULD use the
extension ".mks".
o As a general rule of thumb for all codecs, information that is
global to an entire stream SHOULD be stored in the CodecPrivate
element.
o Start and stop timecodes that are used in a timecodes native
storage format SHOULD be removed when being placed in Matroska as
they could interfere if the file is edited afterwards. Instead,
the Blocks timecode and Duration SHOULD be used to say when the
timecode is displayed.
o Because a "subtitle" stream is actually just an overlay stream,
anything with a transparency layer could be use, including video.
33. Images Subtitles
The first image format that is a goal to import into Matroska is the
VobSub subtitle format. This subtitle type is generated by exporting
the subtitles from a DVD.
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The requirement for muxing VobSub into Matroska is v7 subtitles (see
first line of the .IDX file). If the version is smaller, you must
remux them using the SubResync utility from VobSub 2.23 (or MPC) into
v7 format. Generally any newly created subs will be in v7 format.
The .IFO file will not be used at all.
If there is more than one subtitle stream in the VobSub set, each
stream will need to be separated into separate tracks for storage in
Matroska. E.g. the VobSub file contains streams for both English and
German subtitles. Then the resulting Matroska file SHOULD contain
two tracks. That way the language information can be 'dropped' and
mapped to Matroska's language tags.
The .IDX file is reformatted (see below) and placed in the
CodecPrivate.
Each .BMP will be stored in its own Block. The Timestamp with be
stored in the Blocks Timecode and the duration will be stored in the
Default Duration.
Here is an example .IDX file:
# VobSub index file, v7 (do not modify this line!)
#
# To repair desyncronization, you can insert gaps this way:
# (it usually happens after vob id changes)
#
# delay: [sign]hh:mm:ss:ms
#
# Where:
# [sign]: +, - (optional)
# hh: hours (0 <= hh)
# mm/ss: minutes/seconds (0 <= mm/ss <= 59)
# ms: milliseconds (0 <= ms <= 999)
#
# Note: You can't position a sub before the previous with a negative
# value.
#
# You can also modify timestamps or delete a few subs you don't like.
# Just make sure they stay in increasing order.
# Settings
# Original frame size
size: 720x480
# Origin, relative to the upper-left corner, can be overloaded by
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# aligment
org: 0, 0
# Image scaling (hor,ver), origin is at the upper-left corner or at
# the alignment coord (x, y)
scale: 100%, 100%
# Alpha blending
alpha: 100%
# Smoothing for very blocky images (use OLD for no filtering)
smooth: OFF
# In millisecs
fadein/out: 50, 50
# Force subtitle placement relative to (org.x, org.y)
align: OFF at LEFT TOP
# For correcting non-progressive desync. (in millisecs or hh:mm:ss:ms)
# Note: Not effective in DirectVobSub, use "delay: ... " instead.
time offset: 0
# ON: displays only forced subtitles, OFF: shows everything
forced subs: OFF
# The original palette of the DVD
palette: 000000, 7e7e7e, fbff8b, cb86f1, 7f74b8, e23f06, 0a48ea, \
b3d65a, 6b92f1, 87f087, c02081, f8d0f4, e3c411, 382201, e8840b, fdfdfd
# Custom colors (transp idxs and the four colors)
custom colors: OFF, tridx: 0000, colors: 000000, 000000, 000000, \
000000
# Language index in use
langidx: 0
# English
id: en, index: 0
# Decomment next line to activate alternative name in DirectVobSub /
# Windows Media Player 6.x
# alt: English
# Vob/Cell ID: 1, 1 (PTS: 0)
timestamp: 00:00:01:101, filepos: 000000000
timestamp: 00:00:08:708, filepos: 000001000
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First, lines beginning with "#" are removed. These are comments to
make text file editing easier, and as this is not a text file, they
aren't needed.
Next remove the "langidx" and "id" lines. These are used to
differenciate the subtitle streams and define the language. As the
streams will be stored seperately anyway, there is no need to
differenciate them here. Also, the language setting will be stored
in the Matroska tags, so there is no need to store it here.
Finally, the "timestamp" will be used to set the Block's timecode.
Once it is set there, there is no need for it to be stored here.
Also, as it may interfere if the file is edited, it SHOULD NOT be
stored here.
Once all of these items are removed, the data to store in the
CodecPrivate SHOULD look like this:
size: 720x480
org: 0, 0
scale: 100%, 100%
alpha: 100%
smooth: OFF
fadein/out: 50, 50
align: OFF at LEFT TOP
time offset: 0
forced subs: OFF
palette: 000000, 7e7e7e, fbff8b, cb86f1, 7f74b8, e23f06, 0a48ea, \
b3d65a, 6b92f1, 87f087, c02081, f8d0f4, e3c411, 382201, e8840b, fdfdfd
custom colors: OFF, tridx: 0000, colors: 000000, 000000, 000000, \
000000
There SHOULD also be two Blocks containing one image each with the
timecodes "00:00:01:101" and "00:00:08:708".
34. SRT Subtitles
SRT is perhaps the most basic of all subtitle formats.
It consists of four parts, all in text..
1. A number indicating which subtitle it is in the sequence. 2.
The time that the subtitle appears on the screen, and then
disappears. 3. The subtitle itself. 4. A blank line indicating
the start of a new subtitle.
When placing SRT in Matroska, part 3 is converted to UTF-8 (S_TEXT/
UTF8) and placed in the data portion of the Block. Part 2 is used to
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set the timecode of the Block, and BlockDuration element. Nothing
else is used.
Here is an example SRT file:
1
00:02:17,440 --> 00:02:20,375
Senator, we're making
our final approach into Coruscant.
2
00:02:20,476 --> 00:02:22,501
Very good, Lieutenant.
In this example, the text "Senator, we're making our final approach
into Coruscant." would be converted into UTF-8 and placed in the
Block. The timecode of the block would be set to "00:02:17,440".
And the BlockDuration element would be set to "00:00:02,935".
The same is repeated for the next subtitle.
Because there are no general settings for SRT, the CodecPrivate is
left blank.
35. SSA/ASS Subtitles
SSA stands for Sub Station Alpha. It's the file format used by the
popular subtitle editor, SubStation Alpha [92]. This format is
widely used by fansubbers.
It allows you to do some advanced display features, like positioning,
karaoke, style managements...
For detailed information on SSA/ASS, see the SSA specs [93]. It
includes an SSA specs description and the avanced features added by
ASS format (standing for Advanced SSA). Because SSA and ASS are so
similar, they are treated the same here.
Like SRT, this format is text based with a particular syntax.
A file consists of 4 or 5 parts, declared ala INI file (but it's not
an INI !)
The first, "[Script Info]" contains some information about the
subtitle file, such as it's title, who created it, type of script and
a very important one : "PlayResY". Be carefull of this value,
everything in your script (font size, positioning) is scaled by it.
Sub Station Alpha uses your desktops Y resolution to write this
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value, so if a friend with a large monitor and a high screen
resolution gives you an edited script, you can mess everything up by
saving the script in SSA with your low-cost monitor.
The second, "[V4 Styles]", is a list of style definitions. A style
describe how will look a text on the screen. It defines font, font
size, primary/.../outile colour, position, aligment etc ...
For example this :
Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, TertiaryColour, BackColour, Bold, Italic, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, AlphaLevel, Encoding
Style: Wolf main,Wolf_Rain,56,15724527,15724527,15724527,4144959,0,0,1,1,2,2,5,5,30,0,0
The third, "[Events]", is the list of text you want to display at the
right timing. You can specify some attribute here. Like the style
to use for this event (MUST be defined in the list), the position of
the text (Left, Right, Vertical Margin), an effect. Name is mostly
used by translator to know who said this sentence. Timing is in
h:mm:ss.cc (centisec).
Format: Marked, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: Marked=0,0:02:40.65,0:02:41.79,Wolf main,Cher,0000,0000,0000,,Et les enregistrements de ses ondes delta ?
Dialogue: Marked=0,0:02:42.42,0:02:44.15,Wolf main,autre,0000,0000,0000,,Toujours rien.
"[Pictures]" or "[Fonts]" part can be found in some SSA file, they
contains UUE-encoded pictures/font but those features are only used
by Sub Station Alpha, i.e. no filter (Vobsub/Avery Lee Subtiler
filter) use them.
Now, how are they stored in Matroska ?
o All text is converted to UTF-8* All the headers are stored in
CodecPrivate ( Script Info and the Styles list)* Start & End field
are used to set TimeStamp and the BlockDuration element. the data
stored is :* Events are stored in the Block in this order:
ReadOrder, Layer, Style, Name, MarginL, MarginR, MarginV, Effect,
Text (Layer comes from ASS specs ... it's empty for SSA.)
"ReadOrder field is needed for the decoder to be able to reorder
the streamed samples as they were placed originally in the file."
Here is an example of an SSA file.
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[Script Info]
; This is a Sub Station Alpha v4 script.
; For Sub Station Alpha info and downloads,
; go to [http://www.eswat.demon.co.uk/](http://www.eswat.demon.co.uk/)
; or email [kotus@eswat.demon.co.uk](mailto:kotus@eswat.demon.co.uk)
Title: Wolf's rain 2
Original Script: Anime-spirit Ishin-francais
Original Translation: Coolman
Original Editing: Spikewolfwood
Original Timing: Lord_alucard
Original Script Checking: Spikewolfwood
ScriptType: v4.00
Collisions: Normal
PlayResY: 1024
PlayDepth: 0
Wav: 0, 128697,D:\Alex\Anime\- Fansub -\- TAFF -\Wolf's Rain\WR_-_02_Wav.wav
Wav: 0, 120692,H:\team truc\WR_-_02.wav
Wav: 0, 116504,E:\sub\wolf's_rain\WOLF'S RAIN 02.wav
LastWav: 3
Timer: 100,0000
[V4 Styles]
Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, TertiaryColour, BackColour, Bold, Italic, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, AlphaLevel, Encoding
Style: Default,Arial,20,65535,65535,65535,-2147483640,-1,0,1,3,0,2,30,30,30,0,0
Style: Titre_episode,Akbar,140,15724527,65535,65535,986895,-1,0,1,1,0,3,30,30,30,0,0
Style: Wolf main,Wolf_Rain,56,15724527,15724527,15724527,4144959,0,0,1,1,2,2,5,5,30,0,0
[Events]
Format: Marked, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: Marked=0,0:02:40.65,0:02:41.79,Wolf main,Cher,0000,0000,0000,,Et les enregistrements de ses ondes delta ?
Dialogue: Marked=0,0:02:42.42,0:02:44.15,Wolf main,autre,0000,0000,0000,,Toujours rien.
Here is what would be placed into the CodecPrivate element.
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[Script Info]
; This is a Sub Station Alpha v4 script.
; For Sub Station Alpha info and downloads,
; go to [http://www.eswat.demon.co.uk/](http://www.eswat.demon.co.uk/)
; or email [kotus@eswat.demon.co.uk](mailto:kotus@eswat.demon.co.uk)
Title: Wolf's rain 2
Original Script: Anime-spirit Ishin-francais
Original Translation: Coolman
Original Editing: Spikewolfwood
Original Timing: Lord_alucard
Original Script Checking: Spikewolfwood
ScriptType: v4.00
Collisions: Normal
PlayResY: 1024
PlayDepth: 0
Wav: 0, 128697,D:\Alex\Anime\- Fansub -\- TAFF -\Wolf's Rain\WR_-_02_Wav.wav
Wav: 0, 120692,H:\team truc\WR_-_02.wav
Wav: 0, 116504,E:\sub\wolf's_rain\WOLF'S RAIN 02.wav
LastWav: 3
Timer: 100,0000
[V4 Styles]
Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, TertiaryColour, BackColour, Bold, Italic, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, AlphaLevel, Encoding
Style: Default,Arial,20,65535,65535,65535,-2147483640,-1,0,1,3,0,2,30,30,30,0,0
Style: Titre_episode,Akbar,140,15724527,65535,65535,986895,-1,0,1,1,0,3,30,30,30,0,0
Style: Wolf main,Wolf_Rain,56,15724527,15724527,15724527,4144959,0,0,1,1,2,2,5,5,30,0,0
And here are the two blocks that would be generated.
Block's timecode: 00:02:40.650 BlockDuration: 00:00:01.140
1,,Wolf main,Cher,0000,0000,0000,,Et les enregistrements de ses ondes delta ?
Block's timecode: 00:02:42.420 BlockDuration: 00:00:01.730
2,,Wolf main,autre,0000,0000,0000,,Toujours rien.
36. USF Subtitles
Under construction
37. WebVTT
The "Web Video Text Tracks Format" (short: WebVTT) is developed by
the World Wide Web Consortium (W3C) [94]. Its specifications are
freely available [95].
The guiding principles for the storage of WebVTT in Matroska are:
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o Consistency: store data in a similar way to other subtitle codecs
o Simplicity: making decoding and remuxing as easy as possible for
existing infrastructures
o Completeness: keeping as much data as possible from the original
WebVTT file
37.1. Storage of WebVTT in Matroska
37.1.1. CodecID: codec identification
The CodecID to use is S_TEXT/WEBVTT.
37.1.2. CodecPrivate: storage of gloal WebVTT blocks
This element contains all global blocks before the first subtitle
entry. This starts at the "WEBVTT" file identification marker but
excludes the optional byte order mark.
37.1.3. Storage of non-global WebVTT blocks
Non-global WebVTT blocks (e.g. "NOTE") before a WebVTT Cue Text are
stored in Matroska's BlockAddition element together with the Matroska
Block containing the WebVTT Cue Text these blocks precede (see below
for the actual format).
37.1.4. Storage of Cues in Matroska blocks
Each WebVTT Cue Text is stored directly in the Matroska Block.
A muxer MUST change all WebVTT Cue Timestamps present within the Cue
Text to be relative to the Matroska Block's timestamp.
The Cue's start timestamp is used as the Matroska Block's timestamp.
The difference between the Cue's end timestamp and its start
timestamp is used as the Matroska Block's duration.
37.1.5. BlockAdditions: storing non-global WebVTT blocks, Cue Settings
Lists and Cue identifiers
Each Matroska Block may be accompanied by one BlockAdditions element.
Its format is as follows:
1. The first line contains the WebVTT Cue Text's optional Cue
Settings List followed by one line feed character (U+0x000a).
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The Cue Settings List may be empty in which case the line
consists of the line feed character only.
2. The second line contains the WebVTT Cue Text's optional Cue
Identifier followed by one line feed character (U+0x000a). The
line may be empty indicating that there was no Cue Identifier in
the source file in which case the line consists of the line feed
character only.
3. The third and all following lines contain all WebVTT Comment
Blocks that precede the current WebVTT Cue Block. These may be
absent.
If there is no Matroska BlockAddition element stored together with
the Matroska Block then all three components (Cue Settings List, Cue
Identifier, Cue Comments) MUST be assumed to be absent.
37.2. Examples of transformation
Here's an example how a WebVTT is transformed.
37.2.1. Example WebVTT file
Let's take the following example file:
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WEBVTT with text after the signature
STYLE
::cue {
background-image: linear-gradient(to bottom, dimgray, lightgray);
color: papayawhip;
}
/* Style blocks cannot use blank lines nor "dash dash greater than" */
NOTE comment blocks can be used between style blocks.
STYLE
::cue(b) {
color: peachpuff;
}
REGION
id:bill
width:40%
lines:3
regionanchor:0%,100%
viewportanchor:10%,90%
scroll:up
NOTE
Notes always span a whole block and can cover multiple
lines. Like this one.
An empty line ends the block.
hello
00:00:00.000 --> 00:00:10.000
Example entry 1: Hello <b>world</b>.
NOTE style blocks cannot appear after the first cue.
00:00:25.000 --> 00:00:35.000
Example entry 2: Another entry.
This one has multiple lines.
00:01:03.000 --> 00:01:06.500 position:90% align:right size:35%
Example entry 3: That stuff to the right of the timestamps are cue settings.
00:03:10.000 --> 00:03:20.000
Example entry 4: Entries can even include timestamps.
For example:<00:03:15.000>This becomes visible five seconds
after the first part.
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37.2.2. CodecPrivate
The resulting CodecPrivate element will look like this:
WEBVTT with text after the signature
STYLE
::cue {
background-image: linear-gradient(to bottom, dimgray, lightgray);
color: papayawhip;
}
/* Style blocks cannot use blank lines nor "dash dash greater than" */
NOTE comment blocks can be used between style blocks.
STYLE
::cue(b) {
color: peachpuff;
}
REGION
id:bill
width:40%
lines:3
regionanchor:0%,100%
viewportanchor:10%,90%
scroll:up
NOTE
Notes always span a whole block and can cover multiple
lines. Like this one.
An empty line ends the block.
37.2.3. Storage of Cue 1
Example Cue 1: timestamp 00:00:00.000, duration 00:00:10.000, Block's
content:
Example entry 1: Hello <b>world</b>.
BlockAddition's content starts with one empty line as there's no Cue
Settings List:
hello
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37.2.4. Storage of Cue 2
Example Cue 2: timestamp 00:00:25.000, duration 00:00:10.000, Block's
content:
Example entry 2: Another entry.
This one has multiple lines.
BlockAddition's content starts with two empty lines as there's
neither a Cue Settings List nor a Cue Identifier:
NOTE style blocks cannot appear after the first cue.
37.2.5. Storage of Cue 3
Example Cue 3: timestamp 00:01:03.000, duration 00:00:03.500, Block's
content:
Example entry 3: That stuff to the right of the timestamps are cue settings.
BlockAddition's content ends with an empty line as there's no Cue
Identifier and there were no WebVTT Comment blocks:
position:90% align:right size:35%
37.2.6. Storage of Cue 4
Example Cue 4: timestamp 00:03:10.000, duration 00:00:10.000, Block's
content:
Example entry 4: Entries can even include timestamps. For
example:<00:00:05.000>This becomes visible five seconds after the
first part.
This Block does not need a BlockAddition as the Cue did not contain
an Identifier, nor a Settings List, and it wasn't preceded by Comment
blocks.
37.3. Storage of WebVTT in Matroska vs. WebM
Note: the storage of WebVTT in Matroska is not the same as the design
document for storage of WebVTT in WebM. There are several reasons
for this including but not limited to: the WebM document is old (from
February 2012) and was based on an earlier draft of WebVTT and
ignores several parts that were added to WebVTT later; WebM does
still not support subtitles at all [96]; the proposal suggests
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splitting the information across multiple tracks making demuxer's and
remuxer's life very difficult.
38. HDMV presentation graphics subtitles
The specifications for the HDMV presentation graphics subtitle format
(short: HDMV PGS) can be found in the document "Blu-ray Disc Read-
Only Format; Part 3 -- Audio Visual Basic Specifications" in section
9.14 "HDMV graphics streams".
38.1. Storage of HDMV presentation graphics subtitles
38.1.1. CodecID & CodecPrivate: codec identification
The CodecID to use is "S_HDMV/PGS". A CodecPrivate element is not
used.
38.1.2. Storage of HDMV PGS Segments in Matroska Blocks
Each HDMV PGS Segment (short: Segment) will be stored in a Matroska
Block. A Segment is the data structure described in section 9.14.2.1
"Segment coding structure and parameters" of the Blu-ray
specifications.
Each Segment contains a presentation timestamp. This timestamp will
be used as the timestamp for the Matroska Block.
A Segment is normally shown until a subsequent Segment is
encountered. Therefore the Matroska Block MAY have no Duration. In
that case a player MUST display a Segment within a Matroska Block
until the next Segment is encountered.
A muxer MAY use a Duration, e.g. by calculating the distance between
two subsequent Segments. If a Matroska Block has a Duration, a
player MUST display that Segment only for the duration of the Block's
Duration.
39. HDMV text subtitles
The specifications for the HDMV text subtitle format (short: HDMV
TextST) can be found in the document "Blu-ray Disc Read-Only Format;
Part 3 -- Audio Visual Basic Specifications" in section 9.15 "HDMV
text subtitle streams".
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39.1. Storage of HDMV text subtitles
39.1.1. CodecID & CodecPrivate: codec identification
The CodecID to use is "S_HDMV/TEXTST".
A CodecPrivate Element is required. It MUST contain the stream's
Dialog Style Segment as described in section 9.15.4.2 "Dialog Style
Segment" of the Blu-ray specifications.
39.1.2. Storage of HDMV TextST Dialog Presentation Segments in Matroska
Blocks
Each HDMV Dialog Presentation Segment (short: Segment) will be stored
in a Matroska Block. A Segment is the data structure described in
section 9.15.4.3 "Dialog presentation segment" of the Blu-ray
specifications.
Each Segment contains a start and an end presentation timestamp
(short: start PTS & end PTS). The start PTS will be used as the
timestamp for the Matroska Block. The Matroska Block MUST have a
Duration, and that Duration is the difference between the end PTS and
the start PTS.
A player MUST use the Matroska Block's timestamp and Duration instead
of the Segment's start and end PTS for determining when and how long
to show the Segment.
39.1.3. Character set
When TextST subtitles are stored inside Matroska, the only allowed
character set is UTF-8.
Each HDMV text subtitle stream in a Blu-ray can use one of a handful
of character sets. This information is not stored in the MPEG2
Transport Stream itself but in the accompanying Clip Information
file.
Therefore a muxer MUST parse the accompanying Clip Information file.
If the information indicates a character set other than UTF-8, it
MUST re-encode all text Dialog Presentation Segments from the
indicated character set to UTF-8 prior to storing them in Matroska.
40. Digital Video Broadcasting (DVB) subtitles
The specifications for the Digital Video Broadcasting subtitle
bitstream format (short: DVB subtitles) can be found in the document
"ETSI EN 300 743 - Digital Video Broadcasting (DVB); Subtitling
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systems". The storage of DVB subtitles in MPEG transport streams is
specified in the document "ETSI EN 300 468 - Digital Video
Broadcasting (DVB); Specification for Service Information (SI) in DVB
systems".
40.1. Storage of DVB subtitles
40.1.1. CodecID
The CodecID to use is "S_DVBSUB".
40.1.2. CodecPrivate
The CodecPrivate element is five bytes long and has the following
structure:
o 2 bytes: composition page ID (bit string, left bit first)
o 2 bytes: ancillary page ID (bit string, left bit first)
o 1 byte: subtitling type (bit string, left bit first)
The semantics of these bytes are the same as the ones described in
section 6.2.41 "Subtitling descriptor" of ETSI EN 300 468.
40.1.3. Storage of DVB subtitles in Matroska Blocks
Each Matroska Block consists of one or more DVB Subtitle Segments as
described in segment 7.2 "Syntax and semantics of the subtitling
segment" of ETSI EN 300 743.
Each Matroska Block SHOULD have a Duration indicating how long the
DVB Subtitle Segments in that Block SHOULD be displayed.
41. Tagging
When a Tag is nested within another Tag, the nested Tag becomes an
attribute of the base tag. For instance, if you wanted to store the
dates that a singer used certain addresses for, that singer being the
lead singer for a track that included multiple bands simultaneously,
then your tag tree would look something like this:
o Targets
* TrackUID
o BAND
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* LEADPERFORMER
* ADDRESS
+ DATE
+ DATEEND
* ADDRESS
+ DATE
In this way, it becomes possible to store any Tag as attributes of
another tag.
Multiple items SHOULD never be stored as a list in a single
TagString. If there is more than one tag of a certain type to be
stored, then more than one SimpleTag SHOULD be used.
For authoring Tags outside of EBML, the following XML syntax is
proposed [97] used in mkvmerge [98]. Binary data SHOULD be stored
using BASE64 encoding if it is being stored at authoring time.
41.1. Why official tags matter
There is a debate between people who think all tags SHOULD be free
and those who think all tags SHOULD be strict. If you look at this
page you will realise we are in between.
Advanced-users application might let you put any tag in your file.
But for the rest of the applications, they usually give you a basic
list of tags you can use. Both have their needs. But it's usually a
bad idea to use custom/exotic tags because you will probably be the
only person to use this information even though everyone else could
benefit from it. So hopefully when someone wants to put information
in one's file, they will find an official one that fit them and
hopefully use it ! If it's not in the list, this person can contact
us any time for addition of such a missing tag. But it doesn't mean
it will be accepted... Matroska files are not meant the become a
whole database of people who made costumes for a film. A website
would be better for that... It's hard to define what SHOULD be in and
what doesn't make sense in a file. So we'll treat each request
carefully.
We also need an official list simply for developers to be able to
display relevant information in their own design (if they choose to
support a list of meta-information they SHOULD know which tag has the
wanted meaning so that other apps could understand the same meaning).
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41.2. Tag translations
To be able to save tags from other systems to Matroska we need to
translate them to our system. There is a translation table on our
site [99].
41.3. Tag Formatting
o The TagName SHOULD always be written in all capital letters and
contain no space.
o The fields with dates SHOULD have the following format: YYYY-MM-DD
hh:mm:ss.mss YYYY = Year, MM = Month, DD = Days, HH = Hours, mm =
Minutes, ss = Seconds, mss = Milliseconds. To store less
accuracy, you remove items starting from the right. To store only
the year, you would use, "2004". To store a specific day such as
May 1st, 2003, you would use "2003-05-01".
o Fields that require a Float SHOULD use the "." mark instead of the
"," mark. To display it differently for another local,
applications SHOULD support auto replacement on display. Also, a
thousandths separator SHOULD NOT be used.
o For currency amounts, there SHOULD only be a numeric value in the
Tag. Only numbers, no letters or symbols other than ".". For
instance, you would store "15.59" instead of "$15.59USD".
41.4. Target types
The TargetType element allows tagging of different parts that are
inside or outside a given file. For example in an audio file with
one song you could have information about the album it comes from and
even the CD set even if it's not found in the file.
For application to know what kind of information (like TITLE) relates
to a certain level (CD title or track title), we also need a set of
official TargetType names. For now audio and video will have
different values & names. That also means the same tag name can have
different meanings depending on where it is (otherwise we would end
up with 15 TITLE_ tags).
TargetTypeValue | Audio strings | Video strings | Comment 70 |
COLLECTION | COLLECTION | the high hierarchy consisting of many
different lower items 60 | EDITION / ISSUE / VOLUME / OPUS | SEASON /
SEQUEL / VOLUME | a list of lower levels grouped together 50 | ALBUM
/ OPERA / CONCERT | MOVIE / EPISODE / CONCERT | the most common
grouping level of music and video (equals to an episode for TV
series) 40 | PART / SESSION | PART / SESSION | when an album or
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episode has different logical parts 30 | TRACK / SONG | CHAPTER | the
common parts of an album or a movie 20 | SUBTRACK / PART / MOVEMENT |
SCENE | corresponds to parts of a track for audio (like a movement)
10 | - | SHOT | the lowest hierarchy found in music or movies
An upper level value tag applies to the lower level. That means if a
CD has the same artist for all tracks, you just need to set the
ARTIST tag at level 50 (ALBUM) and not to each TRACK (but you can).
That also means that if some parts of the CD have no known ARTIST the
value MUST be set to nothing (a void string "").
When a level doesn't exist it MUST NOT be specified in the files, so
that the TOTAL_PARTS and PART_NUMBER elements match the same levels.
Here is an example of how these "organizational" tags work: If you
set 10 TOTAL_PARTS to the ALBUM level (40) it means the album
contains 10 lower parts. The lower part in question is the first
lower level that is specified in the file. So if it's TRACK (30)
then that means it contains 10 tracks. If it's MOVEMENT (20) that
means it's 10 movements, etc.
41.5. Official tags
The following is a complete list of the supported Matroska Tags.
While it is possible to use Tag names that are not listed below, this
is not recommended as compatibility will be compromised. If you find
that there is a Tag missing that you would like to use, then please
contact the Matroska team for its inclusion in the specifications
before the format reaches 1.0.
41.6. Nesting Information
Nesting Information tags are intended to contain other tags.
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+----------+-------+------------------------------------------------+
| Tag Name | Type | Description |
+----------+-------+------------------------------------------------+
| ORIGINAL | - | A special tag that is meant to have other tags |
| | | inside (using nested tags) to describe the |
| | | original work of art that this item is based |
| | | on. All tags in this list can be used "under" |
| | | the ORIGINAL tag like LYRICIST, PERFORMER, |
| | | etc. |
| SAMPLE | - | A tag that contains other tags to describe a |
| | | sample used in the targeted item taken from |
| | | another work of art. All tags in this list can |
| | | be used "under" the SAMPLE tag like TITLE, |
| | | ARTIST, DATE_RELEASED, etc. |
| COUNTRY | UTF-8 | The name of the country (biblio ISO-639-2 |
| | | [100]) that is meant to have other tags inside |
| | | (using nested tags) to country specific |
| | | information about the item. All tags in this |
| | | list can be used "under" the COUNTRY_SPECIFIC |
| | | tag like LABEL, PUBLISH_RATING, etc. |
+----------+-------+------------------------------------------------+
41.7. Organization Information
+-------------+-------+---------------------------------------------+
| Tag Name | Type | Description |
+-------------+-------+---------------------------------------------+
| TOTAL_PARTS | UTF-8 | Total number of parts defined at the first |
| | | lower level. (e.g. if TargetType is ALBUM, |
| | | the total number of tracks of an audio CD) |
| PART_NUMBER | UTF-8 | Number of the current part of the current |
| | | level. (e.g. if TargetType is TRACK, the |
| | | track number of an audio CD) |
| PART_OFFSET | UTF-8 | A number to add to PART_NUMBER when the |
| | | parts at that level don't start at 1. (e.g. |
| | | if TargetType is TRACK, the track number of |
| | | the second audio CD) |
+-------------+-------+---------------------------------------------+
41.8. Titles
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+----------+-------+------------------------------------------------+
| Tag Name | Type | Description |
+----------+-------+------------------------------------------------+
| TITLE | UTF-8 | The title of this item. For example, for music |
| | | you might label this "Canon in D", or for |
| | | video's audio track you might use "English |
| | | 5.1" This is akin to the TIT2 tag in ID3. |
| SUBTITLE | UTF-8 | Sub Title of the entity. |
+----------+-------+------------------------------------------------+
41.9. Nested Information
Nested Information includes tags contained in other tags.
+-------------+-------+---------------------------------------------+
| Tag Name | Type | Description |
+-------------+-------+---------------------------------------------+
| URL | UTF-8 | URL corresponding to the tag it's included |
| | | in. |
| SORT_WITH | UTF-8 | A child element to indicate what |
| | | alternative value the parent tag can have |
| | | to be sorted, for example "Pet Shop Boys" |
| | | instead of "The Pet Shop Boys". Or "Marley |
| | | Bob" and "Marley Ziggy" (no comma needed). |
| INSTRUMENTS | UTF-8 | The instruments that are being used/played, |
| | | separated by a comma. It SHOULD be a child |
| | | of the following tags: ARTIST, |
| | | LEAD_PERFORMER or ACCOMPANIMENT. |
| EMAIL | UTF-8 | Email corresponding to the tag it's |
| | | included in. |
| ADDRESS | UTF-8 | The physical address of the entity. The |
| | | address SHOULD include a country code. It |
| | | can be useful for a recording label. |
| FAX | UTF-8 | The fax number corresponding to the tag |
| | | it's included in. It can be useful for a |
| | | recording label. |
| PHONE | UTF-8 | The phone number corresponding to the tag |
| | | it's included in. It can be useful for a |
| | | recording label. |
+-------------+-------+---------------------------------------------+
41.10. Entities
+----------------------+-------+------------------------------------+
| Tag Name | Type | Description |
+----------------------+-------+------------------------------------+
| ARTIST | UTF-8 | A person or band/collective |
| | | generally considered responsible |
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| | | for the work. This is akin to the |
| | | TPE1 tag in ID3 [101]. |
| LEAD_PERFORMER | UTF-8 | Lead Performer/Soloist(s). This |
| | | can sometimes be the same as |
| | | ARTIST. |
| ACCOMPANIMENT | UTF-8 | Band/orchestra/accompaniment/music |
| | | ian. This is akin to the TPE2 tag |
| | | in ID3 [102]. |
| COMPOSER | UTF-8 | The name of the composer of this |
| | | item. This is akin to the TCOM tag |
| | | in ID3 [103]. |
| ARRANGER | UTF-8 | The person who arranged the piece, |
| | | e.g., Ravel. |
| LYRICS | UTF-8 | The lyrics corresponding to a song |
| | | (in case audio synchronization is |
| | | not known or as a doublon to a |
| | | subtitle track). Editing this |
| | | value when subtitles are found |
| | | SHOULD also result in editing the |
| | | subtitle track for more |
| | | consistency. |
| LYRICIST | UTF-8 | The person who wrote the lyrics |
| | | for a musical item. This is akin |
| | | to the TEXT [104] tag in ID3. |
| CONDUCTOR | UTF-8 | Conductor/performer refinement. |
| | | This is akin to the TPE3 [105]. |
| DIRECTOR | UTF-8 | This is akin to the IART tag in |
| | | RIFF [106]. |
| ASSISTANT_DIRECTOR | UTF-8 | The name of the assistant |
| | | director. |
| DIRECTOR_OF_PHOTOGRA | UTF-8 | The name of the director of |
| PHY | | photography, also known as |
| | | cinematographer. This is akin to |
| | | the ICNM tag in Extended RIFF. |
| SOUND_ENGINEER | UTF-8 | The name of the sound engineer or |
| | | sound recordist. |
| ART_DIRECTOR | UTF-8 | The person who oversees the |
| | | artists and craftspeople who build |
| | | the sets. |
| PRODUCTION_DESIGNER | UTF-8 | Artist responsible for designing |
| | | the overall visual appearance of a |
| | | movie. |
| CHOREGRAPHER | UTF-8 | The name of the choregrapher |
| COSTUME_DESIGNER | UTF-8 | The name of the costume designer |
| ACTOR | UTF-8 | An actor or actress playing a role |
| | | in this movie. This is the |
| | | person's real name, not the |
| | | character's name the person is |
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| | | playing. |
| CHARACTER | UTF-8 | The name of the character an actor |
| | | or actress plays in this movie. |
| | | This SHOULD be a sub-tag of an |
| | | "ACTOR" tag in order not to cause |
| | | ambiguities. |
| WRITTEN_BY | UTF-8 | The author of the story or script |
| | | (used for movies and TV shows). |
| SCREENPLAY_BY | UTF-8 | The author of the screenplay or |
| | | scenario (used for movies and TV |
| | | shows). |
| EDITED_BY | UTF-8 | This is akin to the IEDT tag in |
| | | Extended RIFF. |
| PRODUCER | UTF-8 | Produced by. This is akin to the |
| | | IPRO tag in Extended RIFF. |
| COPRODUCER | UTF-8 | The name of a co-producer. |
| EXECUTIVE_PRODUCER | UTF-8 | The name of an executive producer. |
| DISTRIBUTED_BY | UTF-8 | This is akin to the IDST tag in |
| | | Extended RIFF. |
| MASTERED_BY | UTF-8 | The engineer who mastered the |
| | | content for a physical medium or |
| | | for digital distribution. |
| ENCODED_BY | UTF-8 | This is akin to the TENC tag [107] |
| | | in ID3. |
| MIXED_BY | UTF-8 | DJ mix by the artist specified |
| REMIXED_BY | UTF-8 | Interpreted, remixed, or otherwise |
| | | modified by. This is akin to the |
| | | TPE4 tag in ID3 [108]. |
| PRODUCTION_STUDIO | UTF-8 | This is akin to the ISTD tag in |
| | | Extended RIFF. |
| THANKS_TO | UTF-8 | A very general tag for everyone |
| | | else that wants to be listed. |
| PUBLISHER | UTF-8 | This is akin to the TPUB tag in |
| | | ID3 [109]. |
| LABEL | UTF-8 | The record label or imprint on the |
| | | disc. |
+----------------------+-------+------------------------------------+
41.11. Search and Classification
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+---------------------+--------+------------------------------------+
| Tag Name | Type | Description |
+---------------------+--------+------------------------------------+
| GENRE | UTF-8 | The main genre (classical, |
| | | ambient-house, synthpop, sci-fi, |
| | | drama, etc). The format follows |
| | | the infamous TCON tag in ID3. |
| MOOD | UTF-8 | Intended to reflect the mood of |
| | | the item with a few keywords, e.g. |
| | | "Romantic", "Sad" or "Uplifting". |
| | | The format follows that of the |
| | | TMOO tag in ID3. |
| ORIGINAL_MEDIA_TYPE | UTF-8 | Describes the original type of the |
| | | media, such as, "DVD", "CD", |
| | | "computer image," "drawing," |
| | | "lithograph," and so forth. This |
| | | is akin to the TMED tag in ID3 |
| | | [110]. |
| CONTENT_TYPE | UTF-8 | The type of the item. e.g. |
| | | Documentary, Feature Film, |
| | | Cartoon, Music Video, Music, Sound |
| | | FX, ... |
| SUBJECT | UTF-8 | Describes the topic of the file, |
| | | such as "Aerial view of Seattle." |
| DESCRIPTION | UTF-8 | A short description of the |
| | | content, such as "Two birds |
| | | flying." |
| KEYWORDS | UTF-8 | Keywords to the item separated by |
| | | a comma, used for searching. |
| SUMMARY | UTF-8 | A plot outline or a summary of the |
| | | story. |
| SYNOPSIS | UTF-8 | A description of the story line of |
| | | the item. |
| INITIAL_KEY | UTF-8 | The initial key that a musical |
| | | track starts in. The format is |
| | | identical to ID3. |
| PERIOD | UTF-8 | Describes the period that the |
| | | piece is from or about. For |
| | | example, "Renaissance". |
| LAW_RATING | UTF-8 | Depending on the "COUNTRY" it's |
| | | the format of the rating of a |
| | | movie (P, R, X in the USA, an age |
| | | in other countries or a URI |
| | | defining a logo). |
| ICRA | binary | The ICRA [111] content rating for |
| | | parental control. (Previously |
| | | RSACi) |
+---------------------+--------+------------------------------------+
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41.12. Temporal Information
+----------------+-------+------------------------------------------+
| Tag Name | Type | Description |
+----------------+-------+------------------------------------------+
| DATE_RELEASED | UTF-8 | The time that the item was originally |
| | | released. This is akin to the TDRL tag |
| | | in ID3. |
| DATE_RECORDED | UTF-8 | The time that the recording began. This |
| | | is akin to the TDRC tag in ID3. |
| DATE_ENCODED | UTF-8 | The time that the encoding of this item |
| | | was completed began. This is akin to the |
| | | TDEN tag in ID3. |
| DATE_TAGGED | UTF-8 | The time that the tags were done for |
| | | this item. This is akin to the TDTG tag |
| | | in ID3. |
| DATE_DIGITIZED | UTF-8 | The time that the item was transferred |
| | | to a digital medium. This is akin to the |
| | | IDIT tag in RIFF. |
| DATE_WRITTEN | UTF-8 | The time that the writing of the |
| | | music/script began. |
| DATE_PURCHASED | UTF-8 | Information on when the file was |
| | | purchased (see also Section 41.17). |
+----------------+-------+------------------------------------------+
41.13. Spacial Information
+----------------------+-------+------------------------------------+
| Tag Name | Type | Description |
+----------------------+-------+------------------------------------+
| RECORDING_LOCATION | UTF-8 | The location where the item was |
| | | recorded. The countries |
| | | corresponding to the string, same |
| | | 2 octets as in Internet domains |
| | | [112], or possibly ISO-3166 [113]. |
| | | This code is followed by a comma, |
| | | then more detailed information |
| | | such as state/province, another |
| | | comma, and then city. For example, |
| | | "US, Texas, Austin". This will |
| | | allow for easy sorting. It is okay |
| | | to only store the country, or the |
| | | country and the state/province. |
| | | More detailed information can be |
| | | added after the city through the |
| | | use of additional commas. In cases |
| | | where the province/state is |
| | | unknown, but you want to store the |
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| | | city, simply leave a space between |
| | | the two commas. For example, "US, |
| | | , Austin". |
| COMPOSITION_LOCATION | UTF-8 | Location that the item was |
| | | originally designed/written. The |
| | | countries corresponding to the |
| | | string, same 2 octets as in |
| | | Internet domains [114], or |
| | | possibly ISO-3166 [115]. This code |
| | | is followed by a comma, then more |
| | | detailed information such as |
| | | state/province, another comma, and |
| | | then city. For example, "US, |
| | | Texas, Austin". This will allow |
| | | for easy sorting. It is okay to |
| | | only store the country, or the |
| | | country and the state/province. |
| | | More detailed information can be |
| | | added after the city through the |
| | | use of additional commas. In cases |
| | | where the province/state is |
| | | unknown, but you want to store the |
| | | city, simply leave a space between |
| | | the two commas. For example, "US, |
| | | , Austin". |
| COMPOSER_NATIONALITY | UTF-8 | Nationality of the main composer |
| | | of the item, mostly for classical |
| | | music. The countries corresponding |
| | | to the string, same 2 octets as in |
| | | Internet domains [116], or |
| | | possibly ISO-3166 [117]. |
+----------------------+-------+------------------------------------+
41.14. Personal
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+--------------+-------+--------------------------------------------+
| Tag Name | Type | Description |
+--------------+-------+--------------------------------------------+
| COMMENT | UTF-8 | Any comment related to the content. |
| PLAY_COUNTER | UTF-8 | The number of time the item has been |
| | | played. |
| RATING | UTF-8 | A numeric value defining how much a person |
| | | likes the song/movie. The number is |
| | | between 0 and 5 with decimal values |
| | | possible (e.g. 2.7), 5(.0) being the |
| | | highest possible rating. Other rating |
| | | systems with different ranges will have to |
| | | be scaled. |
+--------------+-------+--------------------------------------------+
41.15. Technical Information
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+------------------+--------+---------------------------------------+
| Tag Name | Type | Description |
+------------------+--------+---------------------------------------+
| ENCODER | UTF-8 | The software or hardware used to |
| | | encode this item. ("LAME" or "XviD") |
| ENCODER_SETTINGS | UTF-8 | A list of the settings used for |
| | | encoding this item. No specific |
| | | format. |
| BPS | UTF-8 | The average bits per second of the |
| | | specified item. This is only the data |
| | | in the Blocks, and excludes headers |
| | | and any container overhead. |
| FPS | UTF-8 | The average frames per second of the |
| | | specified item. This is typically the |
| | | average number of Blocks per second. |
| | | In the event that lacing is used, |
| | | each laced chunk is to be counted as |
| | | a separate frame. |
| BPM | UTF-8 | Average number of beats per minute in |
| | | the complete target (e.g. a chapter). |
| | | Usually a decimal number. |
| MEASURE | UTF-8 | In music, a measure is a unit of time |
| | | in Western music like "4/4". It |
| | | represents a regular grouping of |
| | | beats, a meter, as indicated in |
| | | musical notation by the time |
| | | signature.. The majority of the |
| | | contemporary rock and pop music you |
| | | hear on the radio these days is |
| | | written in the 4/4 time signature. |
| TUNING | UTF-8 | It is saved as a frequency in hertz |
| | | to allow near-perfect tuning of |
| | | instruments to the same tone as the |
| | | musical piece (e.g. "441.34" in |
| | | Hertz). The default value is 440.0 |
| | | Hz. |
| REPLAYGAIN_GAIN | binary | The gain to apply to reach 89dB SPL |
| | | on playback. This is based on the |
| | | Replay Gain standard [118]. Note that |
| | | ReplayGain information can be found |
| | | at all TargetType levels (track, |
| | | album, etc). |
| REPLAYGAIN_PEAK | binary | The maximum absolute peak value of |
| | | the item. This is based on the Replay |
| | | Gain standard [119]. |
+------------------+--------+---------------------------------------+
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41.16. Identifiers
+----------------+--------+-----------------------------------------+
| Tag Name | Type | Description |
+----------------+--------+-----------------------------------------+
| ISRC | UTF-8 | The International Standard Recording |
| | | Code [120], excluding the "ISRC" prefix |
| | | and including hyphens. |
| MCDI | binary | This is a binary dump of the TOC of the |
| | | CDROM that this item was taken from. |
| | | This holds the same information as the |
| | | MCDI in ID3. |
| ISBN | UTF-8 | International Standard Book Number |
| | | [121] |
| BARCODE | UTF-8 | EAN-13 [122] (European Article |
| | | Numbering) or UPC-A [123] (Universal |
| | | Product Code) bar code identifier |
| CATALOG_NUMBER | UTF-8 | A label-specific string used to |
| | | identify the release (TIC 01 for |
| | | example). |
| LABEL_CODE | UTF-8 | A 4-digit or 5-digit number to identify |
| | | the record label, typically printed as |
| | | (LC) xxxx or (LC) 0xxxx on CDs medias |
| | | or covers (only the number is stored). |
| LCCN | UTF-8 | Library of Congress Control Number |
| | | [124] |
+----------------+--------+-----------------------------------------+
41.17. Commercial
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+-------------------+-------+---------------------------------------+
| Tag Name | Type | Description |
+-------------------+-------+---------------------------------------+
| PURCHASE_ITEM | UTF-8 | URL to purchase this file. This is |
| | | akin to the WPAY tag in ID3. |
| PURCHASE_INFO | UTF-8 | Information on where to purchase this |
| | | album. This is akin to the WCOM tag |
| | | in ID3. |
| PURCHASE_OWNER | UTF-8 | Information on the person who |
| | | purchased the file. This is akin to |
| | | the TOWN tag in ID3 [125]. |
| PURCHASE_PRICE | UTF-8 | The amount paid for entity. There |
| | | SHOULD only be a numeric value in |
| | | here. Only numbers, no letters or |
| | | symbols other than ".". For instance, |
| | | you would store "15.59" instead of |
| | | "$15.59USD". |
| PURCHASE_CURRENCY | UTF-8 | The currency type used to pay for the |
| | | entity. Use ISO-4217 [126] for the 3 |
| | | letter currency code. |
+-------------------+-------+---------------------------------------+
41.18. Legal
+----------------------+-------+------------------------------------+
| Tag Name | Type | Description |
+----------------------+-------+------------------------------------+
| COPYRIGHT | UTF-8 | The copyright information as per |
| | | the copyright holder. This is akin |
| | | to the TCOP tag in ID3. |
| PRODUCTION_COPYRIGHT | UTF-8 | The copyright information as per |
| | | the production copyright holder. |
| | | This is akin to the TPRO tag in |
| | | ID3. |
| LICENSE | UTF-8 | The license applied to the content |
| | | (like Creative Commons variants). |
| TERMS_OF_USE | UTF-8 | The terms of use for this item. |
| | | This is akin to the USER tag in |
| | | ID3. |
+----------------------+-------+------------------------------------+
41.19. Notes
o In the Target list, a logical OR is applied on all tracks, a
logical OR is applied on all chapters. Then a logical AND is
applied between the Tracks list and the Chapters list to know if
an element belongs to this Target.
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42. Attachments
42.1. Introduction
Matroska supports storage of related files and data in the
Attachments Top-Level Element. Attachments 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 ancilliary files related to the Segment.
"Matroska Readers" MUST NOT execute files stored as Attachments.
42.2. 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 representation still-image depiction of the multimedia
contents of the Matroska file.
Cover art SHOULD only use the JPEG and PNG picture formats.
There can be 2 different covers for a movie/album. A portrait one
(like a DVD case) and a landscape one (like a banner ad for example,
looking better on a wide screen).
There can be 2 versions of the same cover, the "normal cover" and the
"small cover". The dimension of the "normal cover" SHOULD be 600 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 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 and SHOULD all be lower case.
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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42.3. Font files
43. Cues
43.1. Introduction
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 potential Matroska reader with additional
information to use in the optimization of seeking performance.
43.2. 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 Audio tracks SHOULD only be referenced in "CuePoint Elements" if
no video track is present. In this case "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".
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o "CuePoint Elements" SHOULD be numerically sorted in storage order
by the value of the "CueTime Element".
44. Matroska Streaming
There exist multiple ways to stream content. The term streaming
itself is very vague. It means reading a file stored on a server.
But the server could be very distant or very close. The transport
system and the protocol used for streaming makes the whole
difference.
In the case of Matroska, there are mostly 2 different kinds of
stream: file access and live streaming.
45. File Access
File access can simply be reading a file located on your computer,
but also accessing it from an HTTP (web) server or CIFS (windows
share) server. All these protocols are usually safe from reading
errors and seeking in the stream is possible. On other hand when the
file is stored far away or on a slow server, seeking can be an
expensive operation and SHOULD be avoided. That's why we set a few
guidelines [127] that, when followed, help reduce the number of
seeking for regular playback and also have the playback start quickly
without a lot of data needed to read first (like the Cues (index),
Attachments or Meta Seek of all the Clusters).
Matroska having a small overhead, it is well suited for storing
music/videos on file servers without having a big impact on the
bandwidth used. It doesn't require to load the index before playing
(the index can be loaded only when seeking is requested the first
time), so playback can start very quickly too.
46. Live Streaming
Live streaming is the equivalent of TV broadcasting on the internet.
There are 2 families of servers for that. The RTP/RTSP ones and the
HTTP servers. Matroska is not meant to be used over RTP. RTP
already has timing and channel mechanisms that would wasted if
doubled in Matroska. On the other hand live streaming of Matroska
over HTTP (or any other plain protocol based on TCP) is very
possible.
A live Matroska stream is different than a file, because it may have
no known end (only when the client disconnects). For that the
Segment MUST use the "unknown" size (all 1s in the size). The other
option would be to concatenate Segments with known sizes one after
the other. This solution allows a change of codec/resolution between
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each segment which can be useful in some cases (switch between 4:3
and 16:9 in some TV programs for example).
The Segment(s) being continuous, certain elements like Meta Seek,
Cues, Chapters, Attachments MUST NOT be used in this context.
On the player side, it is possible to detect that a stream is not
seekable. If the stream does not have a Meta Seek list or a Cues
list at the beginning of the stream, it SHOULD be considered as non
seekable. Even though it's still theoretically possible to seek
blindly forward in the stream, if the server supports it.
In the context of a live radio or even web TV it is possible to "Tag"
the content that is currently playing. The Tags level 1 element can
be placed between Clusters each time necessary. In that case, the
new Tags found MUST reset the previously encountered tags and use the
new values instead (be they empty).
47. Menu Specifications
48. Introduction
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.
49. 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 players, the Control Track will just give
orders to the player and get the actions associated with the
highlights/hotspots.
49.1. Highlights/Hotspots
A highlight is basically a rectangle/key associated with an action
UID. When that rectangle/key is activated, the 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
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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.
So this highlight is sent from the Control Track to the Player. Then
the player has to handle that highlight until it's deactivated (see
Playback features [128])
The highlight contains a UID of the action, a displayable name (UTF-
8), an associated key (list of keys to be defined, probably
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 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 player.
The format used for storing images SHOULD be extensible. For the
moment we'll use PNG and BMP, both with alpha channel.
49.2. Playback features
All the following features will be sent from the Control Track to the
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
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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
timecode. A "Menu Frame" SHOULD be able to contain more that one
action/highlight for a given timecode. (to be determined, EBML format
structure)
49.3. Player requirements
Some 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 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.
50. Working Graph
51. Ideas
52. Data Structure
As a Matroska side project, the obvious choice for storing binary
data is EBML.
53. References
53.1. Normative References
[RFC3339] Klyne, G. and C. Newman, "Date and Time on the Internet:
Timestamps", RFC 3339, DOI 10.17487/RFC3339, July 2002,
<http://www.rfc-editor.org/info/rfc3339>.
[RFC6386] Bankoski, J., Koleszar, J., Quillio, L., Salonen, J.,
Wilkins, P., and Y. Xu, "VP8 Data Format and Decoding
Guide", RFC 6386, DOI 10.17487/RFC6386, November 2011,
<http://www.rfc-editor.org/info/rfc6386>.
53.2. URIs
[1] http://mukoli.free.fr/mcf/mcf.html
[2] https://github.com/Matroska-Org/ebml-specification/blob/master/
specification.markdown
[3] https://datatracker.ietf.org/wg/cellar/charter/
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[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://www.matroska.org/downloads/test_w1.html
[18] {{site.baseurl}}/index.html#Cluster
[19] {{site.baseurl}}/index.html#Timecode
[20] {{site.baseurl}}/notes.html#TimecodeScale
[21] {{site.baseurl}}/index.html#Cluster
[22] {{site.baseurl}}/index.html#Timecode
[23] {{site.baseurl}}/notes.html#Encryption
[24] {{site.baseurl}}/notes.html#unknown-elements
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[25] {{site.baseurl}}/index.html#Cluster
[26] {{site.baseurl}}/index.html#Timecode
[27] {{site.baseurl}}/index.html#TimecodeScale
[28] {{site.baseurl}}/index.html#Cluster
[29] {{site.baseurl}}/index.html#Timecode
[30] {{site.baseurl}}/index.html#Cluster
[31] {{site.baseurl}}/index.html#Timecode
[32] {{site.baseurl}}/index.html#TrackTimeCodeScale
[33] {{site.baseurl}}/notes.html#raw-timecode
[34] {{site.baseurl}}/notes.html#timecode-types
[35] {{site.baseurl}}/notes.html#matroska-version-indicators-
doctypeversion-and-doctypereadversion
[36] {{site.baseurl}}/index.html#StereoMode
[37] {{site.baseurl}}/index.html#TrackOperation
[38] {{site.baseurl}}/index.html#TrackCombinePlanes
[39] {{site.baseurl}}/notes.html#track-operation
[40] {{site.baseurl}}/index.html#StereoMode
[41] {{site.baseurl}}/index.html#TrackOperation
[42] {{site.baseurl}}/index.html#Void
[43] {{site.baseurl}}/order_guidelines.html#tags-end
[44] https://msdn.microsoft.com/en-us/library/windows/desktop/
dd318229(v=vs.85).aspx
[45] https://github.com/mbunkus/mkvtoolnix/blob/master/lib/librmff/
librmff.h
[46] https://github.com/mbunkus/mkvtoolnix/blob/master/lib/librmff/
librmff.h
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[47] https://github.com/mbunkus/mkvtoolnix/blob/master/lib/librmff/
librmff.h
[48] https://github.com/mbunkus/mkvtoolnix/blob/master/lib/librmff/
librmff.h
[49] https://developer.apple.com/library/mac/documentation/QuickTime/
QTFF/QTFFPreface/qtffPreface.html
[50] {{site.baseurl}}/index.html#lacing
[51] http://www.theora.org/doc/Theora.pdf
[52] http://wiki.multimedia.cx/
index.php?title=Apple_ProRes#Frame_layout
[53] https://www.webmproject.org/vp9/
[54] https://datatracker.ietf.org/doc/draft-niedermayer-cellar-ffv1/
[55] http://alac.macosforge.org/trac/browser/trunk/
ALACMagicCookieDescription.txt
[56] {{site.baseurl}}/index.html#lacing
[57] https://xiph.org/vorbis/doc/Vorbis_I_spec.html
[58] https://xiph.org/vorbis/doc/v-comment.html
[59] https://xiph.org/vorbis/doc/Vorbis_I_spec.html
[60] http://flac.sourceforge.net/
[61] https://github.com/mbunkus/mkvtoolnix/blob/master/lib/librmff/
librmff.h
[62] https://github.com/mbunkus/mkvtoolnix/blob/master/lib/librmff/
librmff.h
[63] https://github.com/mbunkus/mkvtoolnix/blob/master/lib/librmff/
librmff.h
[64] https://github.com/mbunkus/mkvtoolnix/blob/master/lib/librmff/
librmff.h
[65] https://github.com/mbunkus/mkvtoolnix/blob/master/lib/librmff/
librmff.h
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[66] https://github.com/mbunkus/mkvtoolnix/blob/master/lib/librmff/
librmff.h
[67] http://msdn.microsoft.com/library/default.asp?url=/library/en-
us/multimed/mmstr_625u.asp
[68] https://developer.apple.com/library/mac/documentation/QuickTime/
QTFF/QTFFPreface/qtffPreface.html
[69] https://developer.apple.com/library/mac/documentation/QuickTime/
QTFF/QTFFPreface/qtffPreface.html
[70] https://developer.apple.com/library/mac/documentation/QuickTime/
QTFF/QTFFPreface/qtffPreface.html
[71] http://tausoft.org/
[72] http://tausoft.org/wiki/True_Audio_Codec_Format
[73] http://www.wavpack.com/
[74] wavpack.html
[75] {{site.baseurl}}/subtitles.html
[76] {{site.baseurl}}/subtitles.html
[77] {{site.baseurl}}/subtitles.html
[78] {{site.baseurl}}/subtitles.html
[79] {{site.baseurl}}/subtitles.html
[80] {{site.baseurl}}/subtitles.html
[81] {{site.baseurl}}/subtitles.html
[82] {{site.baseurl}}/subtitles.html
[83] http://wiki.xiph.org/index.php/OggKate#Matroska_mapping
[84] http://dvd.sourceforge.net/dvdinfo/pci_pkt.html
[85] http://dvd.sourceforge.net/dvdinfo/pci_pkt.html
[86] {{site.baseurl}}/index.html#ChapProcessCodecID
[87] {{site.baseurl}}/index.html#ChapProcessCodecID
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[88] {{site.baseurl}}/index.html#ChapterTranslateID
[89] http://dvd.sourceforge.net/dvdinfo/uops.html
[90] http://www.dvd-replica.com/DVD/
[91] http://dvd.sourceforge.net/dvdinfo/
[92] http://wiki.multimedia.cx/index.php?title=SubStation_Alpha
[93] http://moodub.free.fr/video/ass-specs.doc
[94] https://www.w3.org/
[95] https://w3c.github.io/webvtt/
[96] http://www.webmproject.org/docs/container/
[97] http://www.matroska.org/files/tags/matroskatags.dtd
[98] http://www.bunkus.org/videotools/mkvtoolnix/doc/
mkvmerge.html#mkvmerge.tags
[99] othertagsystems/comparetable.html
[100] http://lcweb.loc.gov/standards/iso639-2/englangn.html#two
[101] http://id3.org/id3v2.3.0#TPE1
[102] http://id3.org/id3v2.3.0#TPE2
[103] http://id3.org/id3v2.3.0#TCOM
[104] http://id3.org/id3v2.3.0#TEXT
[105] http://id3.org/id3v2.3.0#TPE3
[106] http://www.sno.phy.queensu.ca/~phil/exiftool/TagNames/RIFF.html
[107] http://id3.org/id3v2.3.0#TENC
[108] http://id3.org/id3v2.3.0#TPE4
[109] http://id3.org/id3v2.3.0#TPUB
[110] http://id3.org/id3v2.3.0#TMED
[111] http://www.icra.org/
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[112] http://www.iana.org/cctld/cctld-whois.htm
[113] http://www.iso.org/iso/country_codes
[114] http://www.iana.org/cctld/cctld-whois.htm
[115] http://www.iso.org/iso/country_codes
[116] http://www.iana.org/cctld/cctld-whois.htm
[117] http://www.iso.org/iso/country_codes
[118] http://www.replaygain.org/
[119] http://www.replaygain.org/
[120] http://www.ifpi.org/isrc/isrc_handbook.html#Heading198
[121] http://www.isbn-international.org/
[122] http://www.ean-int.org/
[123] http://www.uc-council.org/
[124] http://www.loc.gov/marc/lccn.html
[125] http://id3.org/id3v2.3.0#TOWN
[126] http://www.xe.com/iso4217.htm
[127] {{site.baseurl}}/index.html
[128] {{site.baseurl}}/chapters/menu.html#playback-features
Authors' Addresses
Steve Lhomme
Email: slhomme@matroska.org
Moritz Bunkus
Email: moritz@bunkus.org
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Dave Rice
Email: dave@dericed.com
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