SMPTE ST 429-14:2023-09
Revision of SMPTE ST 429-14:2014
SMPTE Standard

D-Cinema Packaging — Aux Data Track File

Approved - 2023-09-12

Table of contents🔗

  1. Foreword
  2. Introduction
  3. 1 Scope
  4. 2 Conformance
  5. 3 Normative references
  6. 4 Terms and definitions
  7. 5 Carrying Data in the MXF Generic Container
    1. 5.1 Frame Wrapping
    2. 5.2 Clip Wrapping
    3. 5.3 Custom Wrapping
    4. 5.4 Element and Item Constraints
  8. 6 KLV Coding of Aux Data Elements
    1. 6.1 Data Element Key
    2. 6.2 Length
    3. 6.3 Value
  9. 7 Constraints
    1. 7.1 general
    2. 7.2 Data Definition Property
  10. 8 Label for Aux Data Essence Container Identification
  11. 9 Aux Data Essence Descriptor
  12. 10 Composition Playlist Extensions
    1. 10.1 Extension Elements
    2. 10.2 Namespace
    3. 10.3 AuxData
    4. 10.4 DataEssenceCoding
  13. 11 Schema
  14. Annex A Sample (Informative)
  15. Annex B Additional elements

Foreword🔗

SMPTE (the Society of Motion Picture and Television Engineers) is an internationally-recognized standards developing organization. Headquartered and incorporated in the United States of America, SMPTE has members in over 80 countries on six continents. SMPTE’s Engineering Documents, including Standards, Recommended Practices, and Engineering Guidelines, are prepared by SMPTE’s Technology Committees. Participation in these Committees is open to all with a bona fide interest in their work. SMPTE cooperates closely with other standards-developing organizations, including ISO, IEC and ITU. SMPTE Engineering Documents are drafted in accordance with the rules given in its Standards Operations Manual.

At the time of publication no notice had been received by SMPTE claiming patent rights essential to the implementation of this Engineering Document. However, attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. SMPTE shall not be held responsible for identifying any or all such patent rights.

This document was prepared by Technology Committee 27C.

This edition:

Copyright © 2024, Society of Motion Picture and Television Engineers. All rights reserved. No part of this material may be reproduced, by any means whatsoever, without the prior written permission of the Society of Motion Picture and Television Engineers.

Introduction🔗

This section is entirely informative and does not form an integral part of this Engineering Document.

This document specifies a method for carrying data essence in the MXF Generic Container for use in a D-Cinema Package. This specification is intended to place minimal constraints on the type of data to be carried or how it is used. In order to decode data packaged using the specification, additional information will be needed. While the specification is written to allow synchronization of the data track with picture or sound, the synchronization mechanism is outside the scope of this document. The abbreviation “aux” is used in place of the word “auxiliary” throughout the document, but the terms are interchangeable. The term “aux” is preferred.

1 Scope🔗

This standard specifies the mapping of unspecified data into the Data Element of the MXF Generic Container for use within a Digital Cinema Package. The MXF Generic Container (GC) is described in SMPTE ST 379-1.

This standard specifies the Key, the Length and the Value fields of the Aux Data Element. This standard also defines the Essence Container and the Essence Descriptor.

This standard defines the Composition Playlist asset type extension required for inclusion of an Aux Data track.

2 Conformance🔗

Normative text is text that describes elements of the design that are indispensable or contains the conformance language keywords: "shall", "should", or "may". Informative text is text that is potentially helpful to the user, but not indispensable, and can be removed, changed, or added editorially without affecting interoperability. Informative text does not contain any conformance keywords.

All text in this document is, by default, normative, except: the Introduction, any section explicitly labeled as "Informative" or individual paragraphs that start with "Note:"

The keywords "shall" and "shall not" indicate requirements strictly to be followed in order to conform to the document and from which no deviation is permitted.

The keywords, "should" and "should not" indicate that, among several possibilities, one is recommended as particularly suitable, without mentioning or excluding others; or that a certain course of action is preferred but not necessarily required; or that (in the negative form) a certain possibility or course of action is deprecated but not prohibited.

The keywords "may" and "need not" indicate courses of action permissible within the limits of the document.

The keyword "reserved" indicates a provision that is not defined at this time, shall not be used, and may be defined in the future. The keyword "forbidden" indicates "reserved" and in addition indicates that the provision will never be defined in the future.

A conformant implementation according to this document is one that includes all mandatory provisions ("shall") and, if implemented, all recommended provisions ("should") as described. A conformant implementation need not implement optional provisions ("may") and need not implement them as described.

Unless otherwise specified, the order of precedence of the types of normative information in this document shall be as follows: Normative prose shall be the authoritative definition; Tables shall be next; then formal languages; then figures; and then any other language forms.

3 Normative references🔗

The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

4 Terms and definitions🔗

For the purposes of this document, the terms and definitions given in the following documents apply:

5 Carrying Data in the MXF Generic Container🔗

5.1 Frame Wrapping🔗

The Frame Wrapping method for data essence is illustrated in Figure 1. Frame wrapping shall be used for the Aux Data track file.

Figure 1 shows a series of data elements, each wrapped in a single Content Package Data Element with no other Generic Container Elements in the Container. Each Content Package has the duration of one edit unit.

Figure 1 –⁠ Simple Representation of Frame Wrapping (Informative).

The Frame Wrapping method enables frame by frame access by MXF applications which process at the KLV level. Sufficient Information is provided to allow individual frames to be identified at the KLV level without an MXF decoder having to parse or decode the Essence Data. Each data frame shall be KLV wrapped using a GC Data Element Key.

5.2 Clip Wrapping🔗

Clip wrapping shall not be used in an Aux Data track file.

5.3 Custom Wrapping🔗

Custom wrapping shall not be used in an Aux Data track file.

5.4 Element and Item Constraints🔗

Only Data Elements shall be carried in an Aux Data track file. Each Data Item shall contain only a single Data Element.

6 KLV Coding of Aux Data Elements🔗

6.1 Data Element Key🔗

The values of the first 12 bytes of the essence element key are defined in SMPTE ST 379-1. The other bytes are defined in Table 1.

Table 1 –⁠ Essence Key Bytes 13-16
Byte No. Description Value (hex) Meaning
13 Item Type Identifier 17h GC Data Item
14 Essence Element Count Xx Count of Data Elements in this Generic Container
15 Essence Element Type 0Dh Aux Data Frame-wrapped Element
16 Essence Element Number Yy The number (used as an index) of this Data Element in this Generic Container

6.2 Length🔗

The length field and its application shall comply with SMPTE ST 377-1.

6.3 Value🔗

The value field shall comprise data intended to have a decoded duration of one edit unit. Data wrapped this way should be decodable as an individual edit unit.

7 Constraints🔗

7.1 general🔗

The Aux Data Track file shall be constrained to comply with SMPTE ST 429-3 with respect to pattern, header metadata, and asset identity constraints.

7.2 Data Definition Property🔗

The Data Definition property of the Sequence owned by the Data Track shall be equal to:

urn:smpte:ul:060e2b34.04010101.01030202.03000000

8 Label for Aux Data Essence Container Identification🔗

The value for the Essence Container UL shall be as given in Table 2.

Table 2 –⁠ Specification of the Essence Container Label
Byte No. Description Value (hex) Meaning
1-12 Defined by Generic Container
13 Essence Container Kind 02h MXF Generic Container
14 Mapping Kind 13h Aux Data
15 Content Kind 02h Aux Data Frame-wrapped Element
16 Reserved 01h

The Essence Container UL is used within a batch of ULs in Partition Packs and the Preface set and on its own in the Essence Descriptor.

9 Aux Data Essence Descriptor🔗

The File Descriptor sets are those structural metadata sets in the Header Metadata that describe the essence and metadata elements defined in this document. The Aux Data Essence Descriptor shall be a sub-class of the Generic Data Essence Descriptor, as defined in SMPTE ST 377-1. File Descriptor sets shall be present in the Header Metadata for each Essence Element. Implementations that carry specific data types may extend the Aux Data Essence Descriptor using a sub-descriptor. Implementations complying with this specification shall ignore unrecognized sub-descriptors.

Table 3 –⁠ Aux Data Essence Descriptor
Item Name Type Len Local Tag UL Designator Req ? Meaning Default
Aux Data Essence Descriptor Set UL 16 dyn 06.0E.2B.34.02.7F.01.01.0D.01.01.01.01.01.73.00 Req Defines the Data Essence Descriptor Set (a collection of Parametric metadata)  
Length BER Length var     Req Set length  
All items from the Generic Data Essence Descriptor in SMPTE ST 377-1 to be included. Data Essence Coding usage is modified as specified below.

The DataEssenceCoding item shall be present in in the Aux Data Essence Descriptor.

All other items use the default value as specified in SMPTE ST 377-1.

10 Composition Playlist Extensions🔗

10.1 Extension Elements🔗

To reference the Auxiliary Data essence in a Composition, the extension elements defined in this section shall be used to extend the Reel element of a Composition Playlist, as specified in SMPTE ST 429-7.

10.2 Namespace🔗

The AuxData extension element defined in this specification shall be associated with a unique XML namespace name that shall be the string value http://www.smpte-ra.org/schemas/429-14/2014/Aux-Data. This namespace name conveys both structural and semantic version information, and serves the purpose of a traditional version number field.

XML namespace names used in this standard are identified in Table 4. Namespace names are represented as Uniform Resource Identifier (URI) values as defined in IETF RFC 3986.

Table 4 –⁠ XML Namespaces
Qualifier URI
cpl http://www.smpte-ra.org/schemas/429-7/2006/CPL
axd http://www.smpte-ra.org/schemas/429-14/2014/Aux-Data

Although a URI value begins with a method element (http in this case), the value is designed primarily to be a unique string and does not necessarily correspond to an actual on-line resource. Applications implementing this standard should not attempt to resolve URI values on-line.

URIs listed in Table 4 are normative, whereas the namespace qualifier values themselves (used in Table 4 and elsewhere in this standard) are not normative. Thus, namespace qualifier values may be replaced in instance documents by any arbitrary XML-compliant namespace qualifier, meaning that conformant implementations shall expect any XML-compliant namespace qualifier value that is associated with a URI from Datatypes from other schemas that are used in this document will be prefixed with the appropriate namespace qualifier (e.g. xs:dateTime). See W3C XML Schema Part 2: Datatypes for further information about these types.

Annex A contains a Composition Playlist sample that illustrates the extension element defined in this specification

10.3 AuxData🔗

The AuxData extension element defines the Auxiliary Data asset intended for use with the composition. The actual data essence is contained in an external Track File.

The AuxData element shall be an instance of the DataTrackFileAssetType element, which is derived from the TrackFileAssetType whose structure is defined in SMPTE ST 429-7.

The element defined below replicate values contained in the underlying track file and shall remain consistent with the content of the underlying track file at all times. It is included in the Composition Playlist to alleviate the need for theater management software to access and parse individual track files when scheduling content. In the event an inconsistency exists, the values contained in the underlying track file shall take precedence.

10.4 DataEssenceCoding🔗

The DataEssenceCoding element is a UL that matches the value of the Data Essence Coding parameter of the Aux Data Essence Descriptor (Clause 9). This allows identification of the type of data essence that is referenced by the AuxData track. It shall be coded as type urn:smpte:ul as specified in SMPTE ST 2029.

11 Schema🔗

The XML Schema document presented at Element a conforms to W3C XML Schema Part 1: Structures. It normatively defines the structure of the Composition Playlist extension previously described using a machine-readable language. While this schema is intended to faithfully represent the structure presented in the normative prose portions of this specification, conflicts in definition may occur. In the event of such a conflict, the normative prose shall be the authoritative expression of the standard.

Annex A
Sample (Informative)🔗

A Composition Playlist (CPL) Reel sample is provided below to illustrate implementation of the extension element defined in this specification.

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<cpl:CompositionPlaylist
  xmlns:cpl="http://www.smpte-ra.org/schemas/429-7/2006/CPL">
  <cpl:Id>urn:uuid:55c74f73-2b20-458d-9d05-389ec7f8bc3d</cpl:Id>
  <cpl:IssueDate>2012-06-01T17:44:36+00:00</cpl:IssueDate>
  <cpl:ContentTitleText>Example Aux Data CPL</cpl:ContentTitleText>
  <cpl:ContentKind>test</cpl:ContentKind>
  <cpl:ContentVersion>
    <cpl:Id>urn:uuid:07254436-5254-45ae-8ac3-5e380135b7f5</cpl:Id>
    <cpl:LabelText></cpl:LabelText>
  </cpl:ContentVersion>
  <cpl:RatingList/>
  <cpl:ReelList>
    <cpl:Reel>
      <cpl:Id>urn:uuid:117120ab-07eb-4a26-8356-ce28e7b4a8cf</cpl:Id>
      <cpl:AnnotationText>Reel #1 of The Jazz Singer</cpl:AnnotationText>
      <cpl:AssetList>
        <cpl:MainPicture>
          <cpl:Id>urn:uuid:8a212f2b-e753-4161-a115-733c3b15f62d</cpl:Id>
          <cpl:AnnotationText>Picture for Reel #1 of The Jazz Singer</cpl:AnnotationText>
          <cpl:EditRate>24 1</cpl:EditRate>
          <cpl:IntrinsicDuration>3800</cpl:IntrinsicDuration>
          <cpl:EntryPoint>100</cpl:EntryPoint>
          <cpl:Duration>3600</cpl:Duration>
          <cpl:KeyId>urn:uuid:7f70a22d-489a-4272-8697-bb649f9f35d8</cpl:KeyId>
          <cpl:FrameRate>24 1</cpl:FrameRate>
          <cpl:ScreenAspectRatio>185 100</cpl:ScreenAspectRatio>
        </cpl:MainPicture>
        <cpl:MainSound>
          <cpl:Id>urn:uuid:d9ba0fb8-40c4-40db-93e3-3d6189904223</cpl:Id>
          <cpl:AnnotationText>Soundtrack for Reel #1 of The Jazz Singer</cpl:AnnotationText>
          <cpl:EditRate>24 1</cpl:EditRate>
          <cpl:IntrinsicDuration>3600</cpl:IntrinsicDuration>
          <cpl:KeyId>urn:uuid:942a31d1-71bc-4272-9a52-cc376859e367</cpl:KeyId>
          <cpl:Language>en-us</cpl:Language>
        </cpl:MainSound>
        <axd:AuxData
          xmlns:axd="http://www.smpte-ra.org/schemas/429-14/2014/Aux-Data">
          <cpl:Id>urn:uuid:92840e55-2c8d-4c84-a688-91a61e602193</cpl:Id>
          <cpl:AnnotationText>Special Data Track</cpl:AnnotationText>
          <cpl:EditRate>24 1</cpl:EditRate>
          <cpl:IntrinsicDuration>3700</cpl:IntrinsicDuration>
          <cpl:EntryPoint>100</cpl:EntryPoint>
          <axd:DataEssenceCoding>urn:smpte:ul:060E2B34.04010105.01020304.00000000
          </axd:DataEssenceCoding>
        </axd:AuxData>
      </cpl:AssetList>
    </cpl:Reel>
  </cpl:ReelList>
</cpl:CompositionPlaylist>

Annex B
Additional elements🔗

This annex lists non-prose elements of this document.

  1. a. XML schema document for the AuxData element (file: AuxData.xsd )