ISO/IEC 23009-1:2014/Amd 2:2015
(Amendment)Information technology — Dynamic adaptive streaming over HTTP (DASH) — Part 1: Media presentation description and segment formats — Amendment 2: Spatial relationship description, generalized URL parameters and other extensions
Information technology — Dynamic adaptive streaming over HTTP (DASH) — Part 1: Media presentation description and segment formats — Amendment 2: Spatial relationship description, generalized URL parameters and other extensions
Technologies de l'information — Diffusion en flux adaptatif dynamique sur HTTP (DASH) — Partie 1: Description de la présentation et formats de remise des médias — Amendement 2: Description des relations spatiales, paramètres URL généralisés et autres extensions
General Information
Relations
Standards Content (Sample)
INTERNATIONAL ISO/IEC
STANDARD 23009-1
Second edition
2014-05-15
AMENDMENT 2
2015-07-01
Information technology — Dynamic
adaptive streaming over HTTP
(DASH) —
Part 1:
Media presentation description and
segment formats
AMENDMENT 2: Spatial relationship
description, generalized URL parameters
and other extensions
Technologies de l’information — Diffusion en flux adaptatif
dynamique sur HTTP (DASH) —
Partie 1: Description de la présentation et formats de remise des médias
AMENDEMENT 2: Description des relations spatiales, paramètres URL
généralisés et autres extensions
Reference number
ISO/IEC 23009-1:2014/Amd.2:2015(E)
©
ISO/IEC 2015
---------------------- Page: 1 ----------------------
ISO/IEC 23009-1:2014/Amd.2:2015(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO/IEC 2015, Published in Switzerland
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior
written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of
the requester.
ISO copyright office
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO/IEC 2015 – All rights reserved
---------------------- Page: 2 ----------------------
ISO/IEC 23009-1:2014/Amd 2:2015(E)
Contents Page
Foreword . iv
Introduction . v
Annex H (normative) Spatial Relationship Descriptions . 5
H.1 Spatial Relationship Description (SRD) scheme . 5
H.2 SRD @value syntax . 5
H.3 Examples . 7
H.3.1 Zoomed video . 7
H.3.2 Tiled video . 8
Annex I (normative) Flexible Insertion of URL Parameters . 10
I.1 Introduction . 10
I.2 Syntax . 10
I.2.1 URL Query Information . 11
I.2.4 Examples . 14
© ISO/IEC 2015 – All rights reserved iii
---------------------- Page: 3 ----------------------
ISO/IEC 23009-1:2014/Amd 2:2015(E)
Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are members of
ISO or IEC participate in the development of International Standards through technical committees
established by the respective organization to deal with particular fields of technical activity. ISO and IEC
technical committees collaborate in fields of mutual interest. Other international organizations, governmental
and non-governmental, in liaison with ISO and IEC, also take part in the work. In the field of information
technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of the joint technical committee is to prepare International Standards. Draft International
Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as
an International Standard requires approval by at least 75 % of the national bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
Amendment 2 to ISO/IEC 23009-1:2015 was prepared by Joint Technical Committee ISO/IEC JTC 1,
Information Technology, Subcommittee SC 29, Coding of Audio, Picture, Multimedia and Hypermedia
Information.
iv © ISO/IEC 2015 – All rights reserved
---------------------- Page: 4 ----------------------
ISO/IEC 23009-1:2014/Amd 2:2015(E)
Introduction
This amendment to ISO/IEC 23009-1 adds the ability for MPD authors to express:
- Spatial Relationship Description between Spatial Objects in the MPD;
- Flexible parameter insertions in URLs used to query Media Segments;
- Additional Role @values;
- Association between Representations
© ISO/IEC 2015 – All rights reserved v
---------------------- Page: 5 ----------------------
FINAL DRAFT AMENDMENT ISO/IEC 23009-1:2014/Amd 2:2015(E)
Information Technology — Dynamic adaptive streaming over
HTTP (DASH) — Part 1: Spatial Relationship Description,
Generalized URL parameters and other extensions
In clause 2 "Normative references“, add the following reference, in alphabetical order:
HTML 4.01 Specification, W3C Recommendation, 24 December1999
In clause 3.1 "Terms and definitions", add the following definitions in alphabetical order:
3.1.X
associated Representation
Representation which provides supplemental or descriptive information for at least one other Representation
3.1.X
Spatial Object
a media content component corresponding to a region in a coordinate system associated to this media
content component
In clause 3.2 “Symbols and abbreviated terms”, add the following term:
SRD Spatial Relationship Description
In clause 4.7 “Schemes”, Table 2, add the following identifiers:
Scheme Identifier Clause in Informative description
this part
of ISO/IEC
23009
urn:mpeg:dash:srd:2014 H.1 Scheme identifier for Spatial Relationship
Description
urn:mpeg:dash:urlparam:2014
I.1 Scheme identifier for indicating usage of the
flexible insertion of URL query parameters
urn:mpeg:dash:audio-receiver- 5.8.5.7 Scheme identifier for receiver mix
mix:2014
In clause 5.3.5.1 "Overview", add :
“Associated Representations are described by a Representation element that contains an
@associationId attribute and optionally an @associationType attribute. Associated Representations are
Representations that provide information on their relationships with other Representations. As opposed to
complementary Representations, the segments of an associated Representation may be optional for decoding
© ISO/IEC 2015 – All rights reserved 1
---------------------- Page: 6 ----------------------
ISO/IEC 23009-1:2014/Amd 2:2015(E)
and/or presentation of the Representations identified by @associationId. They can be considered as
supplementary or descriptive information, the type of the association being specified by the
@associationType attribute"
In clause 5.3.5.2 “Representation Semantics”, Table 7 – Semantics of Representation element, add:
@associationId
O specifies all Representations the Representation is
associated with in the decoding and/or presentation process
as a whitespace-separated list of values of
Representation@id attributes.
@associationType O specifies, as a whitespace separated list of values, the kind
of association for each Representation the Representation
has been associated with through the @associationId
attribute. Values taken by this attribute are 4 character
codes for track reference types registered in MP4
registration authority.
This attribute shall not be present when @associationId
is not present.
When present, this attribute must have as many values as
the number of identifiers declared in the @associationId
attribute
NOTE - @associationId and @associationType attributes can only be used between Representations
that are not in the same Adaptation Sets.
In clause 5.8.5.5 “DASH Role scheme”, Table 22, add the following rows:
description Textual or audio media component containing a textual description (intended for
audio synthesis) or an audio description describing a visual component
sign
Visual media component representing a sign-language interpretation of an audio
component.
metadata Media component containing information intended to be processed by application
specific elements.
enhanced-audio-
Audio component with improved intelligibility of the dialogue
intelligibility
In clause 5.8.5.5 “DASH Role scheme”, in Table 22, add the following note:
4) Role descriptors with values such as "subtitle", "caption", "description", "sign" or "metadata"
may be used to enable assignment of a "kind" value in HTML 5 applications for tracks exposed
from a DASH MPD.
Add the following to the end of clause 5.8.5
2 © ISO/IEC 2015 – All rights reserved
---------------------- Page: 7 ----------------------
ISO/IEC 23009-1:2014/Amd 2:2015(E)
5.8.5.7 Audio Receiver Mix
This clause defines a scheme for use in EssentialProperty or SupplementaryProperty to indicate
that two audio Adaptation Sets need to be mixed by the media engine prior to playback.
The @schemeIdUri attribute identifying the scheme is urn:mpeg:dash:audio-receiver-mix:2014.
The @value attribute shall contain the value of the AdaptationSet@id attribute from an Adaptation Set
with content type audio which the current Adaptation Set needs to be mixed with in order to provide complete
audio experience.
An example of receiver mix, is the case where a single audio Adaptation Set provides music and effects – i.e.,
complete experience without dialogues, and one or more Adaptation Sets provide dialogues in different
languages. In this case the dialogue Adaptation Sets will depend on music and effects Adaptation Set.
The mixing requirement is unidirectional – i.e., requirement of mixing Representation A with Representation B
when A is selected does not imply that mixing the two is required if B is selected.
© ISO/IEC 2015 – All rights reserved 3
---------------------- Page: 8 ----------------------
ISO/IEC 23009-1:2014/Amd 2:2015(E)
Add the following annexes:
4 © ISO/IEC 2015 – All rights reserved
---------------------- Page: 9 ----------------------
ISO/IEC 23009-1:2014/Amd 2:2015(E)
Annex H
(normative)
Spatial Relationship Description
H.1 Spatial Relationship Description (SRD) scheme
The SRD scheme allows Media Presentation Description authors to express spatial relationships between
Spatial Objects. A Spatial Object is represented by either an Adaptation Set or a Sub-Representation. As an
example, a spatial relationship may express that a video represents a spatial part of another full-frame video
(e.g. a region of interest, or a tile).
The SupplementalProperty and/or EssentialProperty descriptors with @schemeIdUri equal to
"urn:mpeg:dash:srd:2014" are used to provide spatial relationship information associated to the
containing Spatial Object. SRD shall be contained exclusively in these two MPD elements (AdaptationSet
and SubRepresentation).
To preserve the compatibility with legacy clients, MPD shall use SupplementalProperty and
EssentialProperty in such a way that at least one Representation can be interpreted by legacy clients
after discarding the element containing EssentialProperty.
NOTE – Sub-Representation level SRDs may be used to represent Spatial Objects in one Representation
such as HEVC tiling streams. In that case, SRD descriptors may be present at Adaptation Set as well as Sub-
Representation levels.
H.2 SRD @value syntax
The @value of the SupplementalProperty or EssentialProperty elements using the SRD scheme is
a comma separated list of values for SRD parameters.
The source_id parameter provides a unique identifier, within the Period, for the source of the content. It
implicitly defines a coordinate system associated to this source. This coordinate system uses an arbitrary
origin (0; 0); the x-axis is oriented from left to right and the y-axis from top to bottom. All SRD sharing the
same source_id value have the same origin and axes orientations. Spatial relationships for Spatial Objects
using SRD with different source_id values are undefined.
For a given source_id value, a reference space is defined, corresponding to the rectangular region
encompassing the entire source content, whose top-left corner is at the origin of the coordinate system. The
total_width and total_height values in a SRD provide the size of this reference space expressed in
arbitrary units.
NOTE – There may be no Spatial Object in the MPD that covers the entire source of the content, e.g. when
the entire source content is represented by two separate videos.
The object_x and object_y parameters (respectively object_width and object_height) express 2D
positions (respectively 2D sizes) of the associated Spatial Object in the coordinate system associated to the
source. The values of the object_x, object_y, object_width, and object_height parameters are
relative to the values of the total_width and total_height parameters, as defined above. Positions
(object_x, object_y) and sizes (object_width, object_height) of SRDs sharing the same
source_id value may be compared after taking into account the size of the reference space, i.e. after the
object_x and object_width values are divided by the total_width value and the object_y and
object_height values divided by the total_height value of their respective descriptors.
© ISO/IEC 2015 – All rights reserved 5
---------------------- Page: 10 ----------------------
ISO/IEC 23009-1:2014/Amd 2:2015(E)
NOTE – Different total_width and total_height values may be used in different descriptors to provide
positions and sizes information in different units for the same reference space.
MPD authors can express, using the spatial_set_id parameter, that some Spatial Objects, within a given
source_id, have a particular spatial relationship. For instance, an MPD author may group all Adaptation
Sets corresponding to tiles at a same resolution level. This way, the spatial_set_id parameter may be
used by the DASH client to quickly select spatially related Spatial Objects. When multiple full-frame videos
which consist of one or more Spatial Objects with the same total_width and total_height value,
different values of spatial_set_id can be used to distinguish the groups of full-frame video.
NOTE – ISO/IEC 23009-3 gives concrete examples showing how to use the spatial_set_id.
When @value is not present, the SRD does not express any spatial relationship information at all and can be
ignored.
Table H.1 — EssentialProperty@value and/or SupplementalProperty@value attributes for the
SRD scheme
EssentialPropert
Use Description
y@value or
SupplementalProp
erty@value
parameter
source_id
M non-negative integer in decimal representation providing the identifier for the source of
the content
object_x M non-negative integer in decimal representation expressing the horizontal position of the
top-left corner of the Spatial Object in arbitrary units
object_y
M non-negative integer in decimal representation expressing the vertical position of the top-
left corner of the Spatial Object in arbitrary units
object_width M non-negative integer in decimal representation expressing the width of the Spatial Object
in arbitrary units
object_height
M non-negative integer in decimal representation expressing the height of the Spatial
Object in arbitrary units
total_width O optional non-negative integer in decimal representation expressing the width of the
reference space in arbitrary units.
At each Period and for a given source_id value, the following rules apply:
- There shall be at least one descriptor providing a value for the total_width
parameter.
- If two or more descriptors provide different total_width values, all other
descriptors shall explicitly provide the value of total_width.
- If the total_width value is provided in only one descriptor, all other
descriptors are assumed to use that total_width value.
- The value of total_width shall be such that, for each descriptor using this
value of total_width, the sum of object_x and object_width is smaller
or equal to total_width.
When the value total_width is present, the value total_height shall be present.
total_height
O optional non-negative integer in decimal representation expressing the height of the
6 © ISO/IEC 2015 – All rights reserved
---------------------- Page: 11 ----------------------
ISO/IEC 23009-1:2014/Amd 2:2015(E)
reference space in arbitrary units.
At each Period and for a given source_id value, the following rules apply:
- There shall be at least one descriptor providing a value for the total_height
parameter.
- If two or more descriptors provide different total_height values, all other
descriptors shall explicitly provide the value of total_height.
- If the total_height value is provided in only one descriptor, all other
descriptors are assumed to use that total_height value.
- The value of total_height shall be such that, for each descriptor using this
value of total_height, the sum of object_y and object_height is
smaller or equal to total_height.
When the value total_height is present, the value total_width shall be present.
spatial_set_id
O optional non-negative integer in decimal representation providing an identifier for a group
of Spatial Objects.
When not present, the Spatial Object associated to this descriptor does not belong to
any spatial set and no spatial set information is given.
When the value of spatial_set_id is present, the value of total_width and
total_height shall be present.
Legend:
M=Mandatory, O=Optional
H.3 Examples
H.3.1 Zoomed video
This subclause provides a simple example of a static presentation with 2 videos, one video representing a
zoomed part of the other video. The Media Presentation complies with the ISO Base media file format On
Demand profile as defined in 8.3.
xmlns="urn:mpeg:dash:schema:mpd:2011"
type="static"
mediaPresentationDuration="PT10S"
minBufferTime="PT1S"
profiles="urn:mpeg:dash:profile:isoff-on-demand:2011">
Example of a DASH Media Presentation Description using Spatial Relationship Description</br>
to indicate that a video is a zoomed part of another
bandwidth="1055223" startWithSAP="1">
panorama_video.mp4
© ISO/IEC 2015 – All rights reserved 7
---------------------- Page: 12 ----------------------
ISO/IEC 23009-1:2014/Amd 2:2015(E)
bandwidth="769458" startWithSAP="1">
zoomed_video.mp4
H.3.2 Tiled video
This subclause provides a simple example of a static presentation of a video available in different resolutions
and of tiles of that video also available in different resolutions. The Media Presentation complies with the ISO
Base media file format On Demand profile as defined in 8.3.
xmlns="urn:mpeg:dash:schema:mpd:2011"
type="static"
mediaPresentationDuration="PT10S"
min
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.