<?xml version="1.0" encoding="us-ascii"?> version='1.0' encoding='UTF-8'?>
<!DOCTYPE rfc SYSTEM "rfc2629.dtd">
<?rfc toc="yes" ?>
<?rfc compact="yes" ?>
<?rfc subcompact="no"?>
<?rfc sortrefs="yes" ?>
<?rfc symrefs="yes" ?>
<?rfc rfcedstyle="yes" ?> "rfc2629-xhtml.ent">

<rfc docTitle="draft-ietf-clue-data-model-schema-17" xmlns:xi="http://www.w3.org/2001/XInclude" submissionType="IETF"
consensus="yes" consensus="true" category="std"  ipr="trust200902"> ipr="trust200902" number="8846" docName="draft-ietf-clue-data-model-schema-17" obsoletes="" updates="" xml:lang="en" tocInclude="true" sortRefs="true" symRefs="true" version="3">
  <!-- xml2rfc v2v3 conversion 2.37.3 -->
  <front>
<title abbrev="draft-ietf-clue-data-model-schema-17">

<!--[rfced] We have updated the short title that appears in the running header
as follows; please let us know if this is agreeable or if you prefer
otherwise. Also note that the title of the document has been updated as
follows. The abbreviation has been expanded per Section 3.6 of RFC 7322
(“RFC Style Guide”). Please review.

Short title

Original:
   draft-ietf-clue-data-model-schema-17

Current:
   XML Schema for CLUE Data Model

***
Main title

Original:
   An XML Schema for the CLUE data model

Current:
   An XML Schema for the Controlling Multiple
   Streams for Telepresence (CLUE) Data Model
-->
    <title abbrev="An XML Schema for the CLUE Data Model">
		An XML Schema for the Controlling Multiple
   Streams for Telepresence (CLUE) Data Model
</title>
 <seriesInfo name="RFC" value="8846"/>
    <author initials="R." surname="Presta" fullname="Roberta Presta">
      <organization>University of Napoli</organization>
      <address>
        <postal>
          <street>Via Claudio 21</street>
          <code>80125</code>
          <city>Napoli</city>
          <country>Italy</country>
        </postal>
        <email>roberta.presta@unina.it</email>
      </address>
    </author>
    <author initials="S P" P." surname="Romano" fullname="Simon Pietro Romano">
      <organization>University of Napoli</organization>
      <address>
        <postal>
          <street>Via Claudio 21</street>
          <code>80125</code>
          <city>Napoli</city>
          <country>Italy</country>
        </postal>
        <email>spromano@unina.it</email>
      </address>
    </author>
    <date month="August" year="2016"/> month="June" year="2020"/>
    <area>ART</area>
    <workgroup>CLUE Working Group</workgroup>

<!-- [rfced] Please insert any keywords (beyond those that appear in
the title) for use on http://www.rfc-editor.org/rfcsearch.html. -->

    <keyword>CLUE</keyword>
    <keyword>Telepresence</keyword>
    <keyword>Data Model</keyword>
    <keyword>Framework</keyword>
    <abstract>
      <t>
This document provides an XML schema file
for the definition of CLUE data model types. The term "CLUE" stands for
"ControLling mUltiple streams
"Controlling Multiple Streams for tElepresence" Telepresence" and is the name of
the IETF working group in which this document, as well as other
companion documents, has been developed. The document defines a coherent
structure for information associated with the description of a
telepresence scenario.
</t>
    </abstract>
  </front>
  <middle>

<!-- Introduction -->

    <section title="Introduction" anchor="sec-intro"> anchor="sec-intro" numbered="true" toc="default">
      <name>Introduction</name>
      <t>
This document provides an XML schema file
for the definition of CLUE data model types. For the benefit of the
reader, the term 'CLUE' "CLUE" stands for
"ControLling mUltiple streams
"Controlling Multiple Streams for tElepresence" Telepresence" and is the name of
the IETF working group in which this document, as well as other
companion documents, has been developed.
A thorough definition of the CLUE
framework can be found in <xref target="I-D.ietf-clue-framework"/>. target="RFC8845" format="default"/>.
</t>
      <t>
The schema is based on information contained in
<xref target="I-D.ietf-clue-framework"/>. target="RFC8845" format="default"/>.
It encodes information and constraints defined in the
aforementioned document in order to provide a formal representation
of the concepts therein presented.
<!--
</t>
      <t>
<!--[rfced] Please clarify "The document aims at the definition". Is
the intended meaning perhaps 'outlines' or 'specifies' the
definition?

Original:
   The schema document aims at the definition is intended to be modified according to changes
applied to of a coherent structure for
   information associated with the above mentioned CLUE document. description of a telepresence
   scenario.

Perhaps:
   The document specifies the definition of a coherent structure for
   information associated with the description of a telepresence
   scenario.
-->
</t>
<t>
The document aims at the definition of a coherent structure for
information associated with the description of a telepresence
scenario. Such information is used within the CLUE protocol messages
(<xref target="I-D.ietf-clue-protocol"/>)
<xref target="RFC8847" format="default"/>, enabling the dialogue between
a Media Provider and a Media Consumer. CLUE protocol messages, indeed,
are XML messages allowing (i) a Media Provider to advertise its
telepresence capabilities in terms of media captures, capture scenes,
and other features envisioned in the CLUE framework, according to the
format herein defined and (ii) a Media Consumer to request the
desired telepresence options in the form of capture encodings,
represented as described in this document.
</t>
<t>

</t>
    </section>

<!-- Terminology -->

    <section title="Terminology" anchor="sec-teminology"> anchor="sec-teminology" numbered="true" toc="default">
      <name>Terminology</name>
      <t>
    The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", "<bcp14>MUST</bcp14>", "<bcp14>MUST NOT</bcp14>", "<bcp14>REQUIRED</bcp14>", "<bcp14>SHALL</bcp14>", "<bcp14>SHALL
    NOT</bcp14>", "<bcp14>SHOULD</bcp14>", "<bcp14>SHOULD NOT</bcp14>", "<bcp14>RECOMMENDED</bcp14>", "<bcp14>NOT RECOMMENDED</bcp14>",
    "<bcp14>MAY</bcp14>", and "OPTIONAL" "<bcp14>OPTIONAL</bcp14>" in this document are to be interpreted as
    described in BCP&nbsp;14 <xref target="RFC2119"/> <xref target="RFC2119"/>. target="RFC8174"/>
    when, and only when, they appear in all capitals, as shown here.
</t>
    </section>

<!-- Definitions -->

    <section title="Definitions" anchor="sec-definitions">
<t>	This document refers to anchor="sec-definitions" numbered="true" toc="default">
      <name>Definitions</name>

<!-- [rfced] Several of the same definitions used in
<xref target="I-D.ietf-clue-framework"/>, except are for the "CLUE
Participant" definition.
We briefly recall herein some of the main same
terms used in the document.
</t>

<t>
<list style="hanging">

<t hangText="Audio Capture:">
Media Capture for audio.  Denoted as ACn in RFC-to-be 8845, but the examples in this
document.
</t>

<t hangText="Capture:">Same as Media Capture.</t>

<t hangText="Capture Device:">A device that converts physical input,
   such as audio, video or text, into an electrical signal, in most
   cases definitions do not exactly
match. Would you like the definitions to be fed into a updated to exactly match?
(If so, please let us know which to use.)
Alternatively, one document could contain the information, and the
other could refer to it, e.g., "The definitions in RFC 8845 apply here."
Examples:

This document (current):
   Render:  The process of reproducing the received Streams - for
      instance, displaying the remote video on the Media Consumer's
      screens or playing the remote audio through loudspeakers.
vs.

RFC-to-be 8845 (current):
   Render:  The process of generating a representation from media, such
      as displayed motion video or sound emitted from loudspeakers.

This document (current):
   Stream Characteristics:  The union of the features used to describe a
      Stream in the CLUE environment and in the SIP/SDP environment.
vs.

RFC-to-be 8845 (current):
   Stream Characteristics:  The media encoder. stream attributes commonly used in
      non-CLUE SIP/SDP environments (such as media codec, bitrate,
      resolution, profile/level, etc.) as well as CLUE-specific
      attributes, such as the Capture ID or a spatial location.
-->

      <t>This document refers to the same definitions used in
<xref target="RFC8845" format="default"/>, except for the "CLUE
Participant" definition.
We briefly recall herein some of the main terms used in the document.
</t>

<t hangText="Capture Encoding:">A
      <dl newline="false" spacing="normal">
        <dt>Audio Capture:</dt> <dd>Media Capture for audio.  Denoted as "ACn" in the examples in this
document.
</dd>
        <dt>Capture:</dt><dd>Same as Media Capture.</dd>
        <dt>Capture Device:</dt><dd>A device that converts physical input,
   such as audio, video, or text, into an electrical signal, in most
   cases to be fed into a media encoder.
</dd>
        <dt>Capture Encoding:</dt><dd>A specific encoding of a Media Capture,
   to be sent by a Media Provider to a Media Consumer via RTP.
</t>

<t hangText="Capture Scene:">A
</dd>
        <dt>Capture Scene:</dt>
        <dd>A structure representing a spatial region
   captured by one or more Capture Devices, each capturing media
   representing a portion of the region. The spatial region represented
   by a Capture Scene MAY <bcp14>MAY</bcp14> correspond to a real region in physical space,
   such as a room.  A Capture Scene includes attributes and one or more
   Capture Scene Views, with each view including one or more Media
   Captures.
</t>

<t hangText="Capture
</dd>
        <dt>Capture Scene View:"> View:</dt>
        <dd> A list of Media Captures of the same
   media type that together form one way to represent the entire
   Capture Scene.
</t>

<t hangText="CLUE Participant:">
</dd>
<!--[rfced] Should a brief definition of "CLUE Participant" be added
to the following since all of the other terms in this list
include a definition?

Original:
    CLUE Participant:  This term is imported from the CLUE protocol
(<xref target="I-D.ietf-clue-protocol"/>)
    ([I-D.ietf-clue-protocol]) document.
</t>

<t hangText="Consumer:">Short
-->
        <dt>CLUE Participant:</dt>
        <dd>
This term is imported from the CLUE protocol document
<xref target="RFC8847" format="default"/>.
</dd>
        <dt>Consumer:</dt>
        <dd>Short for Media Consumer.</t>

<t hangText="Encoding Consumer.</dd>
        <dt>Encoding or Individual Encoding:"> Encoding:</dt>
        <dd>
	A set of parameters representing a way to encode a Media Capture to
	become a Capture Encoding.
</t>

<t hangText="Encoding Group:">
</dd>
        <dt>Encoding Group:</dt>
        <dd>
	A set of encoding parameters representing a total
	media encoding capability to be sub-divided subdivided across potentially
	multiple Individual Encodings.
</t>

<t hangText="Endpoint">A CLUE-capable device which
</dd>

<!--[rfced] There is the logical point one instance of final termination through receiving, decoding and rendering,
   and/or initiation through capturing, encoding, 'Participant' (capitalized) in
the sentence below; is this referring to the 'CLUE Participant'?
If so, may we add 'CLUE'? If not, and sending of media
   streams. this is a general term, may
we lowercase 'participant'?

Original:
   An endpoint consists of one or more physical devices
   which source and sink media streams, and exactly one
   <xref target="RFC4353"/> [RFC4353]
   Participant (which, in turn, includes exactly one SIP User Agent).
   Endpoints can be anything

Perhaps:
   An endpoint consists of one or more physical devices
   that source and sink media streams and exactly one
   participant [RFC4353] (which, in turn, includes exactly
   one SIP User Agent).
-->
        <dt>Endpoint:</dt>
        <dd>A CLUE-capable device that is the logical point
   of final termination through receiving, decoding, and rendering
   and/or initiation through capturing, encoding, and sending of media
   streams.  An endpoint consists of one or more physical devices
   that source and sink media streams and exactly one
   Participant <xref target="RFC4353" format="default"/> (which, in turn, includes exactly one SIP User Agent).  Endpoints can be anything from multiscreen/multicamera rooms to
   handheld devices.</t>

<t hangText="Media:">Any devices.</dd>
        <dt>Media:</dt>
        <dd>Any data that, after suitable encoding, can be
conveyed over
   RTP, including audio, video video, or timed text.</t>

<t hangText="Media Capture:">A text.</dd>
        <dt>Media Capture:</dt>
        <dd>A source of Media, such as from one or
   more Capture Devices or constructed from other Media streams.
</t>

<t hangText="Media Consumer:">
</dd>
        <dt>Media Consumer:</dt>
        <dd>
	A CLUE-capable device that intends to receive Capture Encodings.
</t>

<t hangText="Media Provider:">
</dd>
        <dt>Media Provider:</dt>
        <dd>
	A CLUE-capable device that intends to send Capture Encodings.
</t>

<t hangText="Multiple
</dd>
        <dt>Multiple Content Capture:"> Capture (MCC):</dt>
        <dd>
	A Capture that mixes and/or switches other Captures of a single
	type (e.g., all audio or all video.) Particular Media Captures
	may or may not be present in the resultant Capture Encoding
	depending on time or space.  Denoted as MCCn "MCCn" in the example cases
	in this document.
</t>

<t hangText="Multipoint
</dd>
        <dt>Multipoint Control Unit (MCU):">A (MCU):</dt>
        <dd>A CLUE-capable device
that connects
   two or more endpoints together into one single multimedia
   conference <xref target="RFC7667"/>. target="RFC7667" format="default"/>.

<!--[rfced] How may we rephrase this sentence in order to avoid
hyphenating "[RFC4353]-like Mixer"?

Original:
   An MCU includes an [RFC4353] like Mixer,
   without the [RFC4353] requirement to send media to each
   participant.

Perhaps:
   An MCU includes a Mixer, similar to those in [RFC4353],
   but without the requirement to send media to each
   participant.
-->
    An MCU includes an
   <xref target="RFC4353"/> target="RFC4353" format="default"/> like Mixer,
   without the <xref target="RFC4353"/> target="RFC4353" format="default"/> requirement to send media to
   each participant.
</t>

<t hangText="Plane
</dd>
        <dt>Plane of Interest:"> Interest:</dt>
        <dd>
	The spatial plane containing the most relevant subject matter.
</t>

<t hangText="Provider:">Same
</dd>
        <dt>Provider:</dt>
        <dd>Same as Media Provider.</t>

<t hangText="Render: ">The Provider.</dd>
        <dt>Render: </dt>
        <dd>The process of reproducing the received Streams
   like, --
   for instance, displaying of the remote video on the Media
   Consumer's screens, screens or playing of the remote audio through
   loudspeakers.
</t>

<t hangText="Scene:">Same
</dd>
        <dt>Scene:</dt>
        <dd>Same as Capture Scene.</t>

<t hangText="Simultaneous Scene.</dd>
        <dt>Simultaneous Transmission Set:"> Set:</dt>
        <dd>
	A set of Media Captures that can be transmitted simultaneously
	from a Media Provider.
</t>

<t hangText="Single
</dd>
        <dt>Single Media Capture:"> Capture:</dt>
        <dd>
	A capture which that contains media from a single
	source capture device, e.g., an audio capture from a single
	microphone,
	microphone or a video capture from a single camera.
</t>

<t hangText="Spatial Relation:">
</dd>
        <dt>Spatial Relation:</dt>
        <dd>
	The arrangement in space of two objects, objects in space, in contrast to relation in
	time or other relationships.
</t>

<t hangText="Stream:">
</dd>
        <dt>Stream:</dt>
        <dd>
	A Capture Encoding sent from a Media Provider to a Media Consumer
	via RTP <xref target="RFC3550"/>.
</t>

<t hangText="Stream Characteristics:">The target="RFC3550" format="default"/>.
</dd>
        <dt>Stream Characteristics:</dt>
        <dd>The union of the features used to
describe
a Stream in the CLUE environment and in the SIP-SDP environment.</t>

<t hangText="Video Capture:">A SIP/SDP environment.</dd>
        <dt>Video Capture:</dt>
        <dd>A Media Capture for video.</t>

</list>
</t> video.</dd>
      </dl>
    </section>

<!-- Schema File -->

    <section title="XML Schema" anchor="sec-schema"> anchor="sec-schema" numbered="true" toc="default">
      <name>XML Schema</name>
      <t>
This section contains the CLUE data model schema definition.
</t>
      <t>
The element and attribute definitions are formal representations of the
concepts
needed to describe the capabilities of a Media Provider and the streams
that are requested by a Media Consumer given the Media Provider's
ADVERTISEMENT (<xref target="I-D.ietf-clue-protocol"/>). <xref target="RFC8847" format="default"/>.
</t>
      <t>The main groups of information are:</t>
<list style="empty">
  <t>&lt;mediaCaptures&gt;: the

      <ul empty="true" spacing="normal">
        <li>
  <dl newline="false" spacing="normal">
  <dt>&lt;mediaCaptures&gt;:</dt><dd>the list of media captures available
  (<xref target="sec-media-captures"/>)</t>
  <t>&lt;encodingGroups&gt;: the target="sec-media-captures" format="default"/>)</dd>

        <dt>&lt;encodingGroups&gt;:</dt><dd>the list of encoding groups
  (<xref target="sec-encoding-groups"/>)</t>
  <t>&lt;captureScenes&gt;: the target="sec-encoding-groups" format="default"/>)</dd>

        <dt>&lt;captureScenes&gt;:</dt><dd>the list of capture scenes
  (<xref target="sec-capture-scenes"/>)</t>
  <t>&lt;simultaneousSets&gt;: the target="sec-capture-scenes" format="default"/>)</dd>

        <dt>&lt;simultaneousSets&gt;:</dt><dd>the list of simultaneous transmission
  sets (<xref target="sec-simultaneous-sets"/>)</t>
  <t>&lt;globalViews&gt;: the target="sec-simultaneous-sets" format="default"/>)</dd>

        <dt>&lt;globalViews&gt;:</dt><dd>the list of global views sets
  (<xref target="sec-global-views"/>)</t>
  <t>&lt;people&gt;: meta data target="sec-global-views" format="default"/>)</dd>

        <dt>&lt;people&gt;:</dt><dd>metadata about the participants represented
  in the telepresence session (<xref target="sec-participants"/>)</t>
  <t>&lt;captureEncodings&gt;: the target="sec-participants" format="default"/>)</dd>

        <dt>&lt;captureEncodings&gt;:</dt><dd>the list of instantiated capture
  encodings (<xref target="sec-capture-encodings"/>)</t>

</list> target="sec-capture-encodings" format="default"/>)</dd>
  </dl></li>
      </ul>
      <t>
All of the above refers refer to concepts that have been
introduced in <xref target="I-D.ietf-clue-framework"/> target="RFC8845" format="default"/>
 and further detailed in this document.
</t>

<figure>
<artwork>
<![CDATA[

<!--[rfced] Is it intentional that the entities &lt; and &gt;
are used in Section 4, but they are not used elsewhere in the
document (for the same text)? For example:

Section 4:
by IANA in the "CLUE Schema &lt;personType&gt; registry"

Section 21.1.3:
by IANA in the "CLUE Schema <personType> registry",
-->

<!--[rfced] FYI, two lines within the XML schema exceed
the 69-character limit, so we inserted a line break as
follows. Please review and and let us know if any further
changes are needed.

Original:
schemaLocation=
  "http://www.iana.org/assignments/xml-registry/schema/vcard-4.0.xsd"/>

Current:
   schemaLocation=
     "https://www.iana.org/assignments/xml-registry/schema/
      vcard-4.0.xsd"/>
-->

<sourcecode type="xml"><![CDATA[
<?xml version="1.0" encoding="UTF-8" ?>
<xs:schema
   targetNamespace="urn:ietf:params:xml:ns:clue-info"
   xmlns:tns="urn:ietf:params:xml:ns:clue-info"
   xmlns:xs="http://www.w3.org/2001/XMLSchema"
   xmlns="urn:ietf:params:xml:ns:clue-info"
   xmlns:xcard="urn:ietf:params:xml:ns:vcard-4.0"
   elementFormDefault="qualified"
   attributeFormDefault="unqualified"
   version="1.0">

<!-- Import xcard xCard XML schema -->
<xs:import namespace="urn:ietf:params:xml:ns:vcard-4.0"
schemaLocation=
  "http://www.iana.org/assignments/xml-registry/schema/vcard-4.0.xsd"/>
  "https://www.iana.org/assignments/xml-registry/schema/
   vcard-4.0.xsd"/>

<!-- ELEMENT DEFINITIONS -->
<xs:element name="mediaCaptures" type="mediaCapturesType"/>
<xs:element name="encodingGroups" type="encodingGroupsType"/>
<xs:element name="captureScenes" type="captureScenesType"/>
<xs:element name="simultaneousSets" type="simultaneousSetsType"/>
<xs:element name="globalViews" type="globalViewsType"/>
<xs:element name="people" type="peopleType"/>

<xs:element name="captureEncodings" type="captureEncodingsType"/>

<!-- MEDIA CAPTURES TYPE -->
<!-- envelope of media captures -->
<xs:complexType name="mediaCapturesType">
 <xs:sequence>
   <xs:element name="mediaCapture" type="mediaCaptureType"
   maxOccurs="unbounded"/>
 </xs:sequence>
</xs:complexType>

<!-- DESCRIPTION element -->
<xs:element name="description">
 <xs:complexType>
  <xs:simpleContent>
   <xs:extension base="xs:string">
     <xs:attribute name="lang" type="xs:language"/>
   </xs:extension>
  </xs:simpleContent>
 </xs:complexType>
</xs:element>

<!-- MEDIA CAPTURE TYPE -->
<xs:complexType name="mediaCaptureType" abstract="true">
  <xs:sequence>
    <!-- mandatory fields -->
    <xs:element name="captureSceneIDREF" type="xs:IDREF"/>
    <xs:choice>
      <xs:sequence>
        <xs:element name="spatialInformation"
                    type="tns:spatialInformationType"/>
      </xs:sequence>
      <xs:element name="nonSpatiallyDefinable" type="xs:boolean"
      fixed="true"/>
    </xs:choice>
    <!-- for handling multi-content multicontent captures: -->
    <xs:choice>
      <xs:sequence>
        <xs:element name="synchronizationID" type="xs:ID"
         minOccurs="0"/>
        <xs:element name="content" type="contentType" minOccurs="0"/>
        <xs:element name="policy" type="policyType" minOccurs="0"/>
        <xs:element name="maxCaptures" type="maxCapturesType"
         minOccurs="0"/>
        <xs:element name="allowSubsetChoice" type="xs:boolean"
         minOccurs="0"/>
      </xs:sequence>
      <xs:element name="individual" type="xs:boolean" fixed="true"/>
    </xs:choice>
    <!-- optional fields -->
    <xs:element name="encGroupIDREF" type="xs:IDREF" minOccurs="0"/>
    <xs:element ref="description" minOccurs="0"
     maxOccurs="unbounded"/>
    <xs:element name="priority" type="xs:unsignedInt" minOccurs="0"/>
    <xs:element name="lang" type="xs:language" minOccurs="0"
     maxOccurs="unbounded"/>
        <xs:element name="mobility" type="mobilityType"
         minOccurs="0" />
    <xs:element ref="presentation" minOccurs="0" />
    <xs:element ref="embeddedText" minOccurs="0" />
    <xs:element ref="view" minOccurs="0" />
    <xs:element name="capturedPeople" type="capturedPeopleType"
     minOccurs="0"/>
    <xs:element name="relatedTo" type="xs:IDREF" minOccurs="0"/>
  </xs:sequence>
  <xs:attribute name="captureID" type="xs:ID" use="required"/>
  <xs:attribute name="mediaType" type="xs:string" use="required"/>

</xs:complexType>

<!-- POLICY TYPE -->
<xs:simpleType name="policyType">
 <xs:restriction base="xs:string">
      <xs:pattern value="([a-zA-Z0-9])+[:]([0-9])+"/>
    </xs:restriction>
</xs:simpleType>

<!-- CONTENT TYPE -->
<xs:complexType name="contentType">
 <xs:sequence>
   <xs:element name="mediaCaptureIDREF" type="xs:IDREF" type="xs:string"
   minOccurs="0" maxOccurs="unbounded"/>
   <xs:element name="sceneViewIDREF" type="xs:IDREF" type="xs:string"
   minOccurs="0" maxOccurs="unbounded"/>
   <xs:any namespace="##other" processContents="lax" minOccurs="0"
   maxOccurs="unbounded"/>
 </xs:sequence>
 <xs:anyAttribute namespace="##other" processContents="lax"/>
</xs:complexType>

<!-- MAX CAPTURES TYPE -->
<xs:simpleType name="positiveShort">
        <xs:restriction base="xs:unsignedShort">
                <xs:minInclusive value="1">
                </xs:minInclusive>
        </xs:restriction>
</xs:simpleType>

<xs:complexType name="maxCapturesType">
        <xs:simpleContent>
                <xs:extension base="positiveShort">
                        <xs:attribute name="exactNumber"
                                type="xs:boolean"/>
                </xs:extension>
        </xs:simpleContent>
</xs:complexType>

<!-- CAPTURED PEOPLE TYPE -->
<xs:complexType name="capturedPeopleType">
 <xs:sequence>
  <xs:element name="personIDREF" type="xs:IDREF"
   maxOccurs="unbounded"/>
 </xs:sequence>
</xs:complexType>

<!-- PEOPLE TYPE -->
<xs:complexType name="peopleType">
 <xs:sequence>
  <xs:element name="person" type="personType" maxOccurs="unbounded"/>
 </xs:sequence>
</xs:complexType>

<!-- PERSON TYPE -->
<xs:complexType name="personType">
  <xs:sequence>
     <xs:element name="personInfo" type="xcard:vcardType"
      maxOccurs="1" minOccurs="0"/>
     <xs:element ref="personType" minOccurs="0"
      maxOccurs="unbounded" />
     <xs:any namespace="##other" processContents="lax" minOccurs="0"
      maxOccurs="unbounded"/>
  </xs:sequence>
  <xs:attribute name="personID" type="xs:ID" use="required"/>
  <xs:anyAttribute namespace="##other" processContents="lax"/>
</xs:complexType>

<!-- PERSON TYPE ELEMENT -->
<xs:element name="personType" type="xs:string">
 <xs:annotation>
  <xs:documentation>
   Acceptable values (enumerations) for this type are managed
   by IANA in the "CLUE Schema &lt;personType&gt; registry",
   accessible at TBD-IANA. https://www.iana.org/assignments/clue.
  </xs:documentation>
 </xs:annotation>
</xs:element>

<!-- VIEW ELEMENT -->
<xs:element name="view" type="xs:string">
 <xs:annotation>
  <xs:documentation>
   Acceptable values (enumerations) for this type are managed
   by IANA in the "CLUE Schema &lt;view&gt; registry",
   accessible at TBD-IANA. https://www.iana.org/assignments/clue.
  </xs:documentation>
 </xs:annotation>
</xs:element>

<!-- PRESENTATION ELEMENT -->
<xs:element name="presentation" type="xs:string">
 <xs:annotation>
  <xs:documentation>
   Acceptable values (enumerations) for this type are managed
   by IANA in the "CLUE Schema &lt;presentation&gt; registry",
   accessible at TBD-IANA. https://www.iana.org/assignments/clue.
  </xs:documentation>
 </xs:annotation>
</xs:element>

<!-- SPATIAL INFORMATION TYPE -->
<xs:complexType name="spatialInformationType">
 <xs:sequence>
  <xs:element name="captureOrigin" type="captureOriginType"
   minOccurs="0"/>
  <xs:element name="captureArea" type="captureAreaType"
   minOccurs="0"/>
  <xs:any namespace="##other" processContents="lax" minOccurs="0"
   maxOccurs="unbounded"/>
 </xs:sequence>
 <xs:anyAttribute namespace="##other" processContents="lax"/>
</xs:complexType>

<!-- POINT TYPE -->
<xs:complexType name="pointType">
 <xs:sequence>
  <xs:element name="x" type="xs:decimal"/>
  <xs:element name="y" type="xs:decimal"/>
  <xs:element name="z" type="xs:decimal"/>
 </xs:sequence>
</xs:complexType>

<!-- CAPTURE ORIGIN TYPE -->
<xs:complexType name="captureOriginType">
  <xs:sequence>
       <xs:element name="capturePoint" type="pointType"></xs:element>
       <xs:element name="lineOfCapturePoint" type="pointType"
        minOccurs="0">
       </xs:element>
  </xs:sequence>
  <xs:anyAttribute namespace="##any" processContents="lax"/>
</xs:complexType>

<!-- CAPTURE AREA TYPE -->
<xs:complexType name="captureAreaType">
 <xs:sequence>
  <xs:element name="bottomLeft" type="pointType"/>
  <xs:element name="bottomRight" type="pointType"/>
  <xs:element name="topLeft" type="pointType"/>
  <xs:element name="topRight" type="pointType"/>
 </xs:sequence>
</xs:complexType>

<!-- MOBILITY TYPE -->
<xs:simpleType name="mobilityType">
 <xs:restriction base="xs:string">
  <xs:enumeration value="static" />
  <xs:enumeration value="dynamic" />
  <xs:enumeration value="highly-dynamic" />
 </xs:restriction>
</xs:simpleType>

<!-- TEXT CAPTURE TYPE -->
<xs:complexType name="textCaptureType">
 <xs:complexContent>
  <xs:extension base="tns:mediaCaptureType">
  <xs:sequence>
  <xs:any namespace="##other" processContents="lax" minOccurs="0"
    maxOccurs="unbounded"/>
  </xs:sequence>
  <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:extension>
 </xs:complexContent>
</xs:complexType>

<!-- OTHER CAPTURE TYPE -->
<xs:complexType name="otherCaptureType">
 <xs:complexContent>
  <xs:extension base="tns:mediaCaptureType">
  <xs:sequence>
  <xs:any namespace="##other" processContents="lax" minOccurs="0"
    maxOccurs="unbounded"/>
  </xs:sequence>
  <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:extension>
 </xs:complexContent>
</xs:complexType>

<!-- AUDIO CAPTURE TYPE -->
<xs:complexType name="audioCaptureType">
 <xs:complexContent>
  <xs:extension base="tns:mediaCaptureType">
   <xs:sequence>
        <xs:element ref="sensitivityPattern" minOccurs="0" />
    <xs:any namespace="##other" processContents="lax" minOccurs="0"
    maxOccurs="unbounded"/>
   </xs:sequence>
   <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:extension>
 </xs:complexContent>
</xs:complexType>

<!-- SENSITIVITY PATTERN ELEMENT -->
<xs:element name="sensitivityPattern" type="xs:string">
 <xs:annotation>
  <xs:documentation>
   Acceptable values (enumerations) for this type are managed by
   IANA in the "CLUE Schema &lt;sensitivityPattern&gt; registry",
   accessible at TBD-IANA. https://www.iana.org/assignments/clue.
  </xs:documentation>
 </xs:annotation>
</xs:element>

<!-- VIDEO CAPTURE TYPE -->
<xs:complexType name="videoCaptureType">
 <xs:complexContent>
  <xs:extension base="tns:mediaCaptureType">
   <xs:sequence>
    <xs:any namespace="##other" processContents="lax" minOccurs="0"
    maxOccurs="unbounded"/>
   </xs:sequence>
   <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:extension>
 </xs:complexContent>
</xs:complexType>

<!-- EMBEDDED TEXT ELEMENT -->
<xs:element name="embeddedText">
 <xs:complexType>
  <xs:simpleContent>
   <xs:extension base="xs:boolean">
    <xs:attribute name="lang" type="xs:language"/>
   </xs:extension>
  </xs:simpleContent>
 </xs:complexType>
</xs:element>

<!-- CAPTURE SCENES TYPE -->
<!-- envelope of capture scenes -->
<xs:complexType name="captureScenesType">
 <xs:sequence>
  <xs:element name="captureScene" type="captureSceneType"
  maxOccurs="unbounded"/>
 </xs:sequence>
</xs:complexType>

<!-- CAPTURE SCENE TYPE -->
<xs:complexType name="captureSceneType">
 <xs:sequence>
  <xs:element ref="description" minOccurs="0" maxOccurs="unbounded"/>
  <xs:element name="sceneInformation" type="xcard:vcardType"
   minOccurs="0"/>
  <xs:element name="sceneViews" type="sceneViewsType" minOccurs="0"/>
  <xs:any namespace="##other" processContents="lax" minOccurs="0"
  maxOccurs="unbounded"/>
 </xs:sequence>
 <xs:attribute name="sceneID" type="xs:ID" use="required"/>
 <xs:attribute name="scale" type="scaleType" use="required"/>
 <xs:anyAttribute namespace="##other" processContents="lax"/>
</xs:complexType>

<!-- SCALE TYPE -->
<xs:simpleType name="scaleType">
 <xs:restriction base="xs:string">
  <xs:enumeration value="mm"/>
  <xs:enumeration value="unknown"/>
  <xs:enumeration value="noscale"/>
 </xs:restriction>
</xs:simpleType>

<!-- SCENE VIEWS TYPE -->
<!-- envelope of scene views of a capture scene -->
<xs:complexType name="sceneViewsType">
 <xs:sequence>
  <xs:element name="sceneView" type="sceneViewType"
  maxOccurs="unbounded"/>
 </xs:sequence>
</xs:complexType>

<!-- SCENE VIEW TYPE -->
<xs:complexType name="sceneViewType">
 <xs:sequence>
  <xs:element ref="description" minOccurs="0" maxOccurs="unbounded"/>
  <xs:element name="mediaCaptureIDs" type="captureIDListType"/>
 </xs:sequence>
 <xs:attribute name="sceneViewID" type="xs:ID" use="required"/>
</xs:complexType>

<!-- CAPTURE ID LIST TYPE -->
<xs:complexType name="captureIDListType">
 <xs:sequence>
  <xs:element name="mediaCaptureIDREF" type="xs:IDREF"
  maxOccurs="unbounded"/>
 </xs:sequence>
</xs:complexType>

<!-- ENCODING GROUPS TYPE -->
<xs:complexType name="encodingGroupsType">
 <xs:sequence>
  <xs:element name="encodingGroup" type="tns:encodingGroupType"
  maxOccurs="unbounded"/>
 </xs:sequence>
</xs:complexType>

<!-- ENCODING GROUP TYPE -->
<xs:complexType name="encodingGroupType">
 <xs:sequence>
  <xs:element name="maxGroupBandwidth" type="xs:unsignedLong"/>
  <xs:element name="encodingIDList" type="encodingIDListType"/>
  <xs:any namespace="##other" processContents="lax" minOccurs="0"
  maxOccurs="unbounded"/>
 </xs:sequence>
 <xs:attribute name="encodingGroupID" type="xs:ID" use="required"/>
 <xs:anyAttribute namespace="##any" processContents="lax"/>
</xs:complexType>

<!-- ENCODING ID LIST TYPE -->
<xs:complexType name="encodingIDListType">
 <xs:sequence>
  <xs:element name="encodingID" type="xs:string"
   maxOccurs="unbounded"/>
 </xs:sequence>
</xs:complexType>

<!-- SIMULTANEOUS SETS TYPE -->
<xs:complexType name="simultaneousSetsType">
 <xs:sequence>
  <xs:element name="simultaneousSet" type="simultaneousSetType"
  maxOccurs="unbounded"/>
 </xs:sequence>
</xs:complexType>

<!-- SIMULTANEOUS SET TYPE -->
<xs:complexType name="simultaneousSetType">
 <xs:sequence>
   <xs:element name="mediaCaptureIDREF" type="xs:IDREF"
   minOccurs="0" maxOccurs="unbounded"/>
   <xs:element name="sceneViewIDREF" type="xs:IDREF"
   minOccurs="0" maxOccurs="unbounded"/>
   <xs:element name="captureSceneIDREF" type="xs:IDREF"
   minOccurs="0" maxOccurs="unbounded"/>
   <xs:any namespace="##other" processContents="lax" minOccurs="0"
   maxOccurs="unbounded"/>
 </xs:sequence>
 <xs:attribute name="setID" type="xs:ID" use="required"/>
 <xs:attribute name="mediaType" type="xs:string"/>
 <xs:anyAttribute namespace="##any" processContents="lax"/>
</xs:complexType>

<!-- GLOBAL VIEWS TYPE -->
<xs:complexType name="globalViewsType">
 <xs:sequence>
  <xs:element name="globalView" type="globalViewType"
  maxOccurs="unbounded"/>
 </xs:sequence>
</xs:complexType>

<!-- GLOBAL VIEW TYPE -->
<xs:complexType name="globalViewType">
 <xs:sequence>
   <xs:element name="sceneViewIDREF" type="xs:IDREF"
    maxOccurs="unbounded"/>
   <xs:any namespace="##other" processContents="lax" minOccurs="0"
   maxOccurs="unbounded"/>
 </xs:sequence>
 <xs:attribute name="globalViewID" type="xs:ID"/>
 <xs:anyAttribute namespace="##any" processContents="lax"/>
</xs:complexType>

<!-- CAPTURE ENCODINGS TYPE -->
<xs:complexType name="captureEncodingsType">
 <xs:sequence>
  <xs:element name="captureEncoding" type="captureEncodingType"
  maxOccurs="unbounded"/>
 </xs:sequence>
</xs:complexType>

<!-- CAPTURE ENCODING TYPE -->
<xs:complexType name="captureEncodingType">
 <xs:sequence>
  <xs:element name="captureID" type="xs:string"/>
  <xs:element name="encodingID" type="xs:string"/>
  <xs:element name="configuredContent" type="contentType"
   minOccurs="0"/>
  <xs:any namespace="##other" processContents="lax" minOccurs="0"
   maxOccurs="unbounded"/>
 </xs:sequence>
 <xs:attribute name="ID" type="xs:ID" use="required"/>
 <xs:anyAttribute namespace="##any" processContents="lax"/>
</xs:complexType>

<!-- CLUE INFO ELEMENT -->
<xs:element name="clueInfo" type="clueInfoType"/>

<!-- CLUE INFO TYPE -->
<xs:complexType name="clueInfoType">
  <xs:sequence>
   <xs:element ref="mediaCaptures"/>
   <xs:element ref="encodingGroups"/>
   <xs:element ref="captureScenes"/>
   <xs:element ref="simultaneousSets" minOccurs="0"/>
   <xs:element ref="globalViews" minOccurs="0"/>
   <xs:element ref="people" minOccurs="0"/>
   <xs:any namespace="##other" processContents="lax" minOccurs="0"
   maxOccurs="unbounded"/>
  </xs:sequence>
  <xs:attribute name="clueInfoID" type="xs:ID" use="required"/>
  <xs:anyAttribute namespace="##other" processContents="lax"/>
</xs:complexType>
</xs:schema>
]]>
</artwork>
</figure>
]]></sourcecode>
      <t>
Following
The following sections describe the XML schema in more detail. As a general
remark, please notice that optional elements that don't define what
their absence means are intended to be associated with undefined
properties.
</t>
</section><!-- XML schema -->
    </section>

    <section title="&lt;mediaCaptures&gt;" anchor="sec-media-captures"> anchor="sec-media-captures" numbered="true" toc="default">
      <name>&lt;mediaCaptures&gt;</name>
      <t>
&lt;mediaCaptures&gt; represents the list of one or more media
captures available at the Media Provider's side.
Each media capture is represented by a &lt;mediaCapture&gt;
element (<xref target="sec-media-capture"/>). target="sec-media-capture" format="default"/>).
</t>
    </section>
    <section title="&lt;encodingGroups&gt;" anchor="sec-encoding-groups"> anchor="sec-encoding-groups" numbered="true" toc="default">
      <name>&lt;encodingGroups&gt;</name>
      <t>
&lt;encodingGroups&gt; represents the list of
the encoding groups organized on the Media Provider's side.
Each encoding group is represented by an
&lt;encodingGroup&gt; element (<xref target="sec-encoding-group"/>). target="sec-encoding-group" format="default"/>).
</t>
    </section>
    <section title="&lt;captureScenes&gt;" anchor="sec-capture-scenes"> anchor="sec-capture-scenes" numbered="true" toc="default">
      <name>&lt;captureScenes&gt;</name>
      <t>
&lt;captureScenes&gt; represents the list of
the capture scenes organized on the Media Provider's side.
Each capture scene is represented by a
&lt;captureScene&gt; element. element (<xref target="sec-capture-scene"/>). target="sec-capture-scene" format="default"/>).
</t>
    </section>
    <section title="&lt;simultaneousSets&gt;"
	anchor="sec-simultaneous-sets"> anchor="sec-simultaneous-sets" numbered="true" toc="default">
      <name>&lt;simultaneousSets&gt;</name>
      <t>
&lt;simultaneousSets&gt; contains the simultaneous
sets indicated by the Media Provider.
Each simultaneous set is represented by a
&lt;simultaneousSet&gt; element. element (<xref target="sec-simultaneous-set"/>). target="sec-simultaneous-set" format="default"/>).
</t>
    </section>
    <section title="&lt;globalViews&gt;" anchor="sec-global-views"> anchor="sec-global-views" numbered="true" toc="default">
      <name>&lt;globalViews&gt;</name>
      <t>
&lt;globalViews&gt; contains a set of alternative representations of
all the scenes that are offered by a Media Provider to a Media Consumer.
Each alternative is named "global view" view", and it is represented by a
&lt;globalView&gt; element. element (<xref target="sec-global-view"/>). target="sec-global-view" format="default"/>).
</t>
    </section>
    <section title="&lt;captureEncodings&gt;"
	anchor="sec-capture-encodings"> anchor="sec-capture-encodings" numbered="true" toc="default">
      <name>&lt;captureEncodings&gt;</name>
      <t>
&lt;captureEncodings&gt; is a list of capture
encodings.
It can represent the list of the desired
capture encodings indicated by the Media Consumer
or the list of instantiated captures on the
provider's side.
Each capture encoding is represented by a
&lt;captureEncoding&gt; element. element (<xref target="sec-capture-encoding"/>). target="sec-capture-encoding" format="default"/>).
</t>
    </section>
    <section title="&lt;mediaCapture&gt;" anchor="sec-media-capture"> anchor="sec-media-capture" numbered="true" toc="default">
      <name>&lt;mediaCapture&gt;</name>
      <t>
A Media Capture is the
fundamental representation of a media flow
that is available on the provider's side.
Media captures are characterized (i) by (i) a set of features
that are independent from the specific type of medium, medium
and (ii) by a set of features that are media-specific. media specific.
The features that are common to all media types appear within
the media capture type, that which has been designed as an abstract
complex type.
Media-specific captures, such as video captures,
audio captures captures, and others, are specializations of that abstract
media capture type, as in a typical generalization-specialization
hierarchy.
</t>
      <t>The following is the XML Schema definition of the
media capture type:
</t>
<t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- MEDIA CAPTURE TYPE -->
<xs:complexType name="mediaCaptureType" abstract="true">
  <xs:sequence>
    <!-- mandatory fields -->
    <xs:element name="captureSceneIDREF" type="xs:IDREF"/>
    <xs:choice>
      <xs:sequence>
        <xs:element name="spatialInformation"
                    type="tns:spatialInformationType"/>
      </xs:sequence>
      <xs:element name="nonSpatiallyDefinable" type="xs:boolean"
      fixed="true"/>
    </xs:choice>
    <!-- for handling multi-content multicontent captures: -->
    <xs:choice>
      <xs:sequence>
        <xs:element name="synchronizationID" type="xs:ID"
         minOccurs="0"/>
        <xs:element name="content" type="contentType" minOccurs="0"/>
        <xs:element name="policy" type="policyType" minOccurs="0"/>
        <xs:element name="maxCaptures" type="maxCapturesType"
         minOccurs="0"/>
        <xs:element name="allowSubsetChoice" type="xs:boolean"
         minOccurs="0"/>
      </xs:sequence>
      <xs:element name="individual" type="xs:boolean" fixed="true"/>
    </xs:choice>
    <!-- optional fields -->
    <xs:element name="encGroupIDREF" type="xs:IDREF" minOccurs="0"/>
    <xs:element ref="description" minOccurs="0"
     maxOccurs="unbounded"/>
    <xs:element name="priority" type="xs:unsignedInt" minOccurs="0"/>
    <xs:element name="lang" type="xs:language" minOccurs="0"
     maxOccurs="unbounded"/>
    <xs:element name="mobility" type="mobilityType" minOccurs="0" />
    <xs:element ref="presentation" minOccurs="0" />
    <xs:element ref="embeddedText" minOccurs="0" />
    <xs:element ref="view" minOccurs="0" />
    <xs:element name="capturedPeople" type="capturedPeopleType"
     minOccurs="0"/>
    <xs:element name="relatedTo" type="xs:IDREF" minOccurs="0"/>
  </xs:sequence>
  <xs:attribute name="captureID" type="xs:ID" use="required"/>
  <xs:attribute name="mediaType" type="xs:string" use="required"/>
</xs:complexType>
]]>
</artwork>
</figure>
</t>
]]></sourcecode>
      <section title="captureID attribute" anchor="sec-captureID"> anchor="sec-captureID" numbered="true" toc="default">
        <name>captureID Attribute</name>
        <t>The "captureID" attribute is a mandatory field
containing the identifier of the media capture.
Such an identifier serves as the way the capture is referenced from
other data model elements (e.g.,  simultaneous sets, capture encodings,
and others via &lt;mediaCaptureIDREF&gt;).
</t>
      </section>
      <section title="mediaType attribute"> numbered="true" toc="default">
        <name>mediaType Attribute</name>
        <t>The "mediaType" attribute is a mandatory attribute specifying
the media type of the capture.
Common standard values are "audio", "video", and "text", as defined in
<xref target="RFC6838"/>. target="RFC6838" format="default"/>.
Other values can be provided. It is assumed that implementations agree
on the interpretation of those other values.
The "mediaType" attribute is as generic as possible. Here is why: (i)
the basic media capture type is an abstract one; (ii) "concrete"
definitions for the standard (<xref target="RFC6838"/>) audio, video video,
and text capture types <xref target="RFC6838" format="default"/> have been specified; (iii) a generic
"otherCaptureType" type has been defined; and (iv) the "mediaType"
attribute has been generically defined as a string, with no particular
template.

From the considerations above, it is clear that if one chooses to rely
on a brand new media type and wants to interoperate with others, an
application-level agreement is needed on how to interpret such
information.
</t>
      </section>
      <section title="&lt;captureSceneIDREF&gt;"> numbered="true" toc="default">
        <name>&lt;captureSceneIDREF&gt;</name>
        <t>&lt;captureSceneIDREF&gt; is a mandatory field
containing the value of the identifier of the capture scene
the media capture is defined in, i.e., the value of the
<xref target="sec-sceneID">sceneID</xref>
sceneID attribute (<xref target="sec-sceneID" format="default"/>) of
that capture scene.
Indeed, each media capture MUST <bcp14>MUST</bcp14> be defined within
one and only one capture scene.
When a media capture is spatially definable, some spatial
information is provided along with it in the form
of point coordinates (see <xref target="sec-spatial-info"/>). target="sec-spatial-info" format="default"/>).
Such coordinates refer to the space of coordinates defined
for the capture scene containing the capture.
</t>
      </section>
      <section title="&lt;encGroupIDREF&gt;"> numbered="true" toc="default">
        <name>&lt;encGroupIDREF&gt;</name>
        <t>&lt;encGroupIDREF&gt; is an optional field
containing the identifier of the encoding group
the media capture is associated with, i.e., the value of the
<xref target="sec-encodingGroupID">encodingGroupID</xref>
encodingGroupID
attribute (<xref target="sec-encodingGroupID" format="default"/>) of that encoding group.
Media captures that are not associated with any encoding group can not cannot
be instantiated as media streams.
</t>
      </section>
      <section title="&lt;spatialInformation&gt;"
anchor="sec-spatial-info"> anchor="sec-spatial-info" numbered="true" toc="default">
        <name>&lt;spatialInformation&gt;</name>
        <t>Media captures are divided into two categories:
(i) non spatially definable captures and
(ii) spatially definable captures.
</t>
        <t>Captures are spatially definable when at least (i) it is possible to
provide (i) the coordinates of the device position within the telepresence
room of origin (capture point) together with its capturing direction
specified by a second point (point on line of capture), capture)
or (ii) it is possible to provide the represented area within
the telepresence room, by listing the coordinates of the four co-planar coplanar
points identifying the plane of interest (area of capture).
The coordinates of the above mentioned points MUST <bcp14>MUST</bcp14> be expressed
according to the coordinate space of the capture scene the media
captures belongs belong to.
</t>
        <t>Non spatially definable captures cannot be characterized
within the physical space of the telepresence room of origin.
Captures of this kind are are, for example example,
those related to recordings, text captures,
DVDs, registered presentations,
or external streams
that are played in the telepresence room
and transmitted to remote sites.
</t>
        <t>
Spatially definable captures represent a
part of the telepresence room.
The captured part of the telepresence room is described
by means of the &lt;spatialInformation&gt; element.
By comparing the &lt;spatialInformation&gt; element
of different media captures within
the same capture scene,
a consumer can better determine the spatial
relationships between them and render them correctly.
Non spatially definable captures do not embed such element elements
in their XML description:
they are instead characterized by having the
&lt;nonSpatiallyDefinable&gt; tag set to "true" (see
<xref target="sub-sec-nonspatiallydef"/>). target="sub-sec-nonspatiallydef" format="default"/>).
</t>

<t>The definition of the spatial information
type is the following:</t>
<t>
<figure>
<artwork>
<![CDATA[

<sourcecode type="xml"><![CDATA[
<!-- SPATIAL INFORMATION TYPE -->
<xs:complexType name="spatialInformationType">
 <xs:sequence>
  <xs:element name="captureOrigin" type="captureOriginType"
   minOccurs="0"/>
  <xs:element name="captureArea" type="captureAreaType"
   minOccurs="0"/>
  <xs:any namespace="##other" processContents="lax" minOccurs="0"
   maxOccurs="unbounded"/>
 </xs:sequence>
 <xs:anyAttribute namespace="##other" processContents="lax"/>
</xs:complexType>
]]>
</artwork>
</figure>
</t>
]]></sourcecode>
        <t>The &lt;captureOrigin&gt; contains the coordinates
of the capture device that is taking the capture (i.e., the capture
point),
point) as well as, optionally, the pointing direction (i.e., the point
on line of capture) (see capture); see <xref target="sec-capture-origin"/>). target="sec-capture-origin" format="default"/>.
</t>
        <t>
The &lt;captureArea&gt; is an optional field
containing four points defining
the captured area covered by the capture
(see <xref target="sec-capture-area"/>). target="sec-capture-area" format="default"/>).
</t>
        <t>The scale of the points coordinates is specified in
the <xref target="sec-scale">scale</xref> scale attribute (<xref target="sec-scale" format="default"/>) of the capture scene
the media capture belongs to.
Indeed, all the spatially definable media captures referring to
the same capture scene share the same coordinate system and express
their spatial information according to the same scale.</t>
        <section title="&lt;captureOrigin&gt;"
anchor="sec-capture-origin"> anchor="sec-capture-origin" numbered="true" toc="default">
          <name>&lt;captureOrigin&gt;</name>
          <t>
The &lt;captureOrigin&gt; element
is used to represent the position and optionally the line of
capture of a capture device.
&lt;captureOrigin&gt; MUST <bcp14>MUST</bcp14> be included in spatially definable audio
captures, while it is optional for spatially definable video captures.
</t><t>
</t>
          <t>
The XML Schema definition of the &lt;captureOrigin&gt;
element type is the following:
</t>
<t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- CAPTURE ORIGIN TYPE -->
<xs:complexType name="captureOriginType">
  <xs:sequence>
        <xs:element name="capturePoint" type="pointType"/>
        <xs:element name="lineOfCapturePoint" type="pointType"
         minOccurs="0"/>
  </xs:sequence>
  <xs:anyAttribute namespace="##any" processContents="lax"/>
</xs:complexType>

<!-- POINT TYPE -->
<xs:complexType name="pointType">
 <xs:sequence>
  <xs:element name="x" type="xs:decimal"/>
  <xs:element name="y" type="xs:decimal"/>
  <xs:element name="z" type="xs:decimal"/>
 </xs:sequence>
</xs:complexType>
]]>
</artwork>
</figure>
</t>
]]></sourcecode>
          <t>
The point type contains three spatial coordinates
(x,y,z) representing a point
in the space associated
with a certain capture scene.
</t>
          <t>
The &lt;captureOrigin&gt; element includes a
mandatory &lt;capturePoint&gt; element and an optional
&lt;lineOfCapturePoint&gt; element,
both of the type "pointType".
&lt;capturePoint&gt; specifies
the three coordinates identifying the position of the
capture device.
&lt;lineOfCapturePoint&gt; is another pointType element representing
the "point on line of capture",  that which gives the pointing direction
of the capture device.
</t>
          <t>
The coordinates of the point on line of capture
MUST NOT
<bcp14>MUST NOT</bcp14> be identical to the capture point coordinates.
For a spatially definable video capture, if the point on line of capture
is provided, it MUST <bcp14>MUST</bcp14> belong to the region between
the point of capture and the capture area.
For a spatially definable audio capture,
if the point on line of capture is not provided,
the sensitivity pattern should be considered omnidirectional.
</t>
        </section>
        <section title="&lt;captureArea&gt;"
anchor="sec-capture-area"> anchor="sec-capture-area" numbered="true" toc="default">
          <name>&lt;captureArea&gt;</name>
          <t>
&lt;captureArea&gt; is an optional element
that can be contained within the spatial information
associated with a media capture.
It represents the spatial area captured by
the media capture.
&lt;captureArea&gt; MUST <bcp14>MUST</bcp14> be included in the spatial information of
spatially definable video captures, while it MUST NOT <bcp14>MUST NOT</bcp14> be associated
with audio captures.
</t>
          <t>
The XML representation of that area is provided
through a set of four point-type elements,
&lt;bottomLeft&gt;, &lt;bottomRight&gt;, &lt;topLeft&gt;,
and &lt;topRight&gt; &lt;topRight&gt;, that MUST <bcp14>MUST</bcp14> be co-planar. coplanar.
The four coplanar points are identified from
the perspective of the capture device.
The XML schema definition is the following:
</t>
<t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- CAPTURE AREA TYPE -->
<xs:complexType name="captureAreaType">
 <xs:sequence>
  <xs:element name="bottomLeft" type="pointType"/>
  <xs:element name="bottomRight" type="pointType"/>
  <xs:element name="topLeft" type="pointType"/>
  <xs:element name="topRight" type="pointType"/>
 </xs:sequence>
</xs:complexType>
]]>
</artwork>
</figure>
</t>
<t>
</t>
]]></sourcecode>
        </section>
      </section> <!-- spatial info section -->

      <section title="&lt;nonSpatiallyDefinable&gt;"
anchor="sub-sec-nonspatiallydef"> anchor="sub-sec-nonspatiallydef" numbered="true" toc="default">
        <name>&lt;nonSpatiallyDefinable&gt;</name>
        <t>When media captures are non spatially definable,
they MUST <bcp14>MUST</bcp14> be marked with the boolean
&lt;nonSpatiallyDefinable&gt;
element set to "true" "true", and no &lt;spatialInformation&gt; MUST <bcp14>MUST</bcp14> be
provided.
Indeed, &lt;nonSpatiallyDefinable&gt; and &lt;spatialInformation&gt;
are mutually
exclusive tags, according to the &lt;choice&gt; section within the XML
Schema definition of the media capture type.
</t>
      </section>
      <section title="&lt;content&gt;" anchor="sub-sec-content"> anchor="sub-sec-content" numbered="true" toc="default">
        <name>&lt;content&gt;</name>
        <t>
A media capture can be (i) an individual media capture or (ii)
a multiple content capture (MCC).
A multiple content capture
an MCC.
An MCC is made by different captures
that can be arranged spatially
(by a composition operation), or temporally (by a switching operation),
or that can result from
the orchestration of both the techniques.
If a media capture is an MCC, then it MAY <bcp14>MAY</bcp14> show in its XML
data model representation the
 &lt;content&gt; element. It is composed by a list of media
  capture identifiers ("mediaCaptureIDREF") and capture scene view
  identifiers ("sceneViewIDREF"),
  where the latter ones are
  used as shortcuts to refer to multiple capture identifiers. The
  referenced captures are used to create the MCC according to a certain
  strategy. If the &lt;content&gt; element does not appear in a an MCC,
  or it has no child elements, then the MCC is assumed to be made
  of multiple sources sources, but no information regarding those sources is
  provided.
</t>
<figure>
<artwork>
<![CDATA[

<!-- Note: FYI, updated the following per the author's email on 10/3/18:

Changed "xs:IDREF" to "xs:string" in two places (in the CONTENT TYPE
schmema below)
-->

<sourcecode type="xml"><![CDATA[
<!-- CONTENT TYPE -->
<xs:complexType name="contentType">
 <xs:sequence>
   <xs:element name="mediaCaptureIDREF" type="xs:IDREF" type="xs:string"
   minOccurs="0" maxOccurs="unbounded"/>
   <xs:element name="sceneViewIDREF" type="xs:IDREF" type="xs:string"
   minOccurs="0" maxOccurs="unbounded"/>
   <xs:any namespace="##other" processContents="lax" minOccurs="0"
   maxOccurs="unbounded"/>
 </xs:sequence>
 <xs:anyAttribute namespace="##other" processContents="lax"/>
</xs:complexType>

]]>
</artwork>
</figure>
]]></sourcecode>
      </section>
      <section title="&lt;synchronizationID&gt;"> numbered="true" toc="default">
        <name>&lt;synchronizationID&gt;</name>
        <t>&lt;synchronizationID&gt; is an optional element for multiple
content captures that
contains a numeric identifier.
Multiple content captures marked with the same identifier in the
&lt;synchronizationID&gt;
contain at all times captures coming from the same sources. It is
   the Media Provider that determines what the source is for the captures
   is. captures.
   In this way, the Media Provider can choose how to group together
   single captures for the purpose of keeping them synchronized
   according to the &lt;synchronizationID&gt; element.
</t>
      </section>
      <section title="&lt;allowSubsetChoice&gt;"> numbered="true" toc="default">
        <name>&lt;allowSubsetChoice&gt;</name>
        <t>&lt;allowSubsetChoice&gt; is an optional boolean element for
multiple content captures.
It indicates whether or not the Provider allows the Consumer to
   choose a specific subset of the captures referenced by the MCC.
   If this attribute is true, and the MCC references other captures,
   then the Consumer MAY <bcp14>MAY</bcp14> specify in a CONFIGURE message a specific
   subset of those captures to be included in the MCC, and the
   Provider MUST <bcp14>MUST</bcp14> then include only that subset.  If this attribute is
   false, or the MCC does not reference other captures, then the
   Consumer MUST NOT <bcp14>MUST NOT</bcp14> select a subset. If &lt;allowSubsetChoice&gt;
   is not shown in the XML description of the
   MCC, its value is to be considered "false".
</t>
      </section>
      <section title="&lt;policy&gt;"> numbered="true" toc="default">
        <name>&lt;policy&gt;</name>
        <t>
&lt;policy&gt; is an optional element
that can be used only for multiple content captures.
It indicates the criteria applied to build the multiple content capture
using the media captures referenced in the &lt;mediaCaptureIDREF&gt;
list.
The &lt;policy&gt; value is in the form of a token that indicates the
policy and an index representing an instance of the policy, separated
by a ":" (e.g., SoundLevel:2, RoundRobin:0, etc.).
The XML schema defining the type of the &lt;policy&gt; element
is the following:
</t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- POLICY TYPE -->
<xs:simpleType name="policyType">
 <xs:restriction base="xs:string">
      <xs:pattern value="([a-zA-Z0-9])+[:]([0-9])+"/>
    </xs:restriction>
</xs:simpleType>
]]>
</artwork>
</figure>
<t>At
]]></sourcecode>

<!--[rfced] Would you like to update this text to exactly
match RFC-to-be 8845? Also, may the lead-in sentence
be updated to be more precise?

Current:
   At the time of writing, only two switching policies are defined in
<xref target="I-D.ietf-clue-framework"/>:</t>
<list>
<t>SoundLevel:
   [RFC8845]:

      SoundLevel:  the content of the MCC is determined by a sound level
         detection algorithm.  The loudest (active) speaker (or a
         previous speaker, depending on the index value) is contained in
         the MCC.  Index 0 represents the most current instance of the
         policy, i.e., the currently active speaker, 1 represents the
         previous instance, i.e., the previous active speaker, and so
         on.
</t>
<t>RoundRobin:

      RoundRobin:  the content of the MCC is determined by a time based algorithm.</t>
</list>
<t>Other values for the &lt;policy&gt; element can be used.
In this case, it is assumed that implementations agree on time-based
         algorithm.

Perhaps (to match 8845):
   At the
meaning time of those other values and/or those new writing, only two switching policies are defined defined;
   there are in later documents.</t>
</section>

<section title="&lt;maxCaptures&gt;" anchor="sub-sec-maxCaptures">
<t>
&lt;maxCaptures&gt; is an optional element [RFC8845] as follows:

   SoundLevel:  This indicates that can be used only for multiple content captures (MCC).
It provides information about the number content of media captures
that can be represented
in the multiple content capture at a time.
If &lt;maxCaptures&gt; MCC is not provided, all determined
      by a sound-level-detection algorithm.  The loudest (active)
      speaker (or a previous speaker, depending on the media captures listed index value) is
      contained in the &lt;content&gt; element can appear at a time in MCC.

   RoundRobin:  This indicates that the capture
encoding. The type definition content of the MCC is provided below.
</t>
<t>
<figure>
<artwork>
<![CDATA[
<!-- MAX CAPTURES TYPE -->
<xs:simpleType name="positiveShort">
	<xs:restriction base="xs:unsignedShort">
		<xs:minInclusive value="1">
		</xs:minInclusive>
	</xs:restriction>
</xs:simpleType>

<xs:complexType name="maxCapturesType"> determined
      by a time-based algorithm.  For example, the Provider provides
      content from a particular source for a period of time and then
      provides content from another source, and so on.
-->

        <t>At the time of writing, only two switching policies are defined in
<xref target="RFC8845" format="default"/>:</t>

<blockquote>
  <dl newline="false" spacing="normal">
   <dt>SoundLevel:</dt><dd>the content of the MCC is
   determined by a sound level detection algorithm. The loudest
   (active) speaker (or a previous speaker, depending on the index
   value) is contained in the MCC. Index 0 represents the most current
   instance of the policy, i.e., the currently active speaker,
   1 represents the previous instance, i.e., the
   previous active speaker, and so on.
</dd>
          <dt>RoundRobin:</dt><dd>the content of the MCC is
   determined by a time-based algorithm.</dd>
        </dl>
</blockquote>
        <t>Other values for the &lt;policy&gt; element can be used.
In this case, it is assumed that implementations agree on the
meaning of those other values and/or those new switching policies
are defined in later documents.</t>
      </section>
      <section anchor="sub-sec-maxCaptures" numbered="true" toc="default">
        <name>&lt;maxCaptures&gt;</name>
        <t>
&lt;maxCaptures&gt; is an optional element
that can be used only for MCCs.
It provides information about the number of media captures
that can be represented
in the multiple content capture at a time.
If &lt;maxCaptures&gt; is not provided, all the media captures listed
in the &lt;content&gt; element can appear at a time in the capture
encoding. The type definition is provided below.
</t>
<sourcecode type="xml"><![CDATA[
<!-- MAX CAPTURES TYPE -->
<xs:simpleType name="positiveShort">
        <xs:restriction base="xs:unsignedShort">
                <xs:minInclusive value="1">
                </xs:minInclusive>
        </xs:restriction>
</xs:simpleType>

<xs:complexType name="maxCapturesType">
        <xs:simpleContent>
                <xs:extension base="positiveShort">
                        <xs:attribute name="exactNumber"
                                type="xs:boolean"/>
                </xs:extension>
        </xs:simpleContent>
</xs:complexType>
]]>
</artwork>
</figure>
</t>
]]></sourcecode>
        <t>When the "exactNumber" attribute is set to "true", it means
the &lt;maxCaptures&gt; element carries the exact number of the
media captures appearing at a time.
Otherwise, the number of the represented media captures MUST <bcp14>MUST</bcp14> be
considered "&lt;=" the &lt;maxCaptures&gt; value.
</t>
        <t>
For instance, an audio MCC having the &lt;maxCaptures&gt; value set to 1
means that a media stream from the MCC will only contain
audio from a single one of its constituent captures at a time.
On the other hand, if the &lt;maxCaptures&gt; value is set to
4 and the exactNumber
attribute is set to "true", it would mean that the media stream
received from the MCC will always contain a mix of audio
from exactly four of its constituent captures.
</t>
      </section>
      <section title="&lt;individual&gt;"> numbered="true" toc="default">
        <name>&lt;individual&gt;</name>
        <t>
&lt;individual&gt; is a boolean element
that MUST <bcp14>MUST</bcp14> be used for single-content captures.
Its value is fixed and set to "true".
Such element indicates the capture that is being described is not
a multiple content capture.
an MCC.
Indeed, &lt;individual&gt; and the aforementioned
tags related to MCC attributes
(from Sections <xref target="sub-sec-content"/> target="sub-sec-content" format="counter"/> to
<xref target="sub-sec-maxCaptures"/>) target="sub-sec-maxCaptures" format="counter"/>) are mutually
exclusive, according to the &lt;choice&gt; section within the XML Schema
definition of the media capture type.
</t>
      </section>
      <section title="&lt;description&gt;"
anchor="sec-description"> anchor="sec-description" numbered="true" toc="default">
        <name>&lt;description&gt;</name>
        <t>
&lt;description&gt;
<!--[rfced] Please clarify "to the aim of providing" in the
following. Could we perhaps replace it with "to provide"?

Original:
   <description> is used to provide human-readable textual information.
   This element is included in the XML definition of media captures,
   capture scenes and capture scene views to the aim of providing
human-readable human-
   readable description of, respectively, media captures, capture scenes
   and capture scene views.
According

Perhaps:
   <description> is used to provide human-readable textual information.
   This element is included in the data model XML definition of media captures,
   capture scenes, and capture scene views to provide human-
   readable descriptions of, respectively, media captures, capture scenes
   and capture scene views.
-->
&lt;description&gt; is used to provide human-readable
textual information.
This element is included in the XML definition of media captures,
capture scenes, and capture scene views to the aim of providing
human-readable descriptions of, respectively,
media captures, capture scenes, and capture scene views.
According to the data model definition of a media capture
(<xref target="sec-media-capture"/>)), target="sec-media-capture" format="default"/>)), zero or more
&lt;description&gt; elements can be used, each
providing information in a different
language.
The &lt;description&gt; element definition is the following:
</t>
<t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- DESCRIPTION element -->
<xs:element name="description">
 <xs:complexType>
  <xs:simpleContent>
   <xs:extension base="xs:string">
     <xs:attribute name="lang" type="xs:language"/>
   </xs:extension>
  </xs:simpleContent>
 </xs:complexType>
</xs:element>
]]>
</artwork>
</figure>
</t>
]]></sourcecode>
        <t>As can be seen, &lt;description&gt; is a
string element with an attribute ("lang") indicating
the language used in the textual description. Such an attribute is
compliant with the Language-Tag ABNF production
from <xref target="RFC5646"/>. target="RFC5646" format="default"/>.
</t>
      </section>
      <section title="&lt;priority&gt;"> numbered="true" toc="default">
        <name>&lt;priority&gt;</name>
        <t>
&lt;priority&gt;
is an optional unsigned integer field
indicating the importance of a media capture
according to the Media Provider's perspective.
It can be used on the receiver's side to
automatically identify
the most relevant contribution from
the Media Provider.
The higher the importance, the lower the contained value.
If no priority
   is assigned, no assumptions regarding relative importance of the
   media capture can be assumed.</t>
      </section>
      <section title="&lt;lang&gt;"> numbered="true" toc="default">
        <name>&lt;lang&gt;</name>
        <t>
&lt;lang&gt; is an optional element
containing the language used in the capture.
Zero or more &lt;lang&gt; elements can appear in the XML description of
a media capture. Each such element has to be compliant with the
Language-Tag ABNF production from <xref target="RFC5646"/>. target="RFC5646" format="default"/>.
</t>
      </section>
      <section title="&lt;mobility&gt;"> numbered="true" toc="default">
        <name>&lt;mobility&gt;</name>
        <t>
&lt;mobility&gt; is an optional element
indicating whether or not the capture device originating
the capture may move during the telepresence session.
That optional element can assume one of the three following values:
<list style="hanging">
<t hangText="static">SHOULD NOT
</t>
<ul empty="true"><li>
        <dl newline="false" spacing="normal">
          <dt>static:</dt>
          <dd><bcp14>SHOULD NOT</bcp14> change for the
duration of the CLUE session, across multiple ADVERTISEMENT messages.
</t>
<t hangText="dynamic">
MAY messages.</dd>
          <dt>dynamic:</dt>
          <dd>
<bcp14>MAY</bcp14> change in each new ADVERTISEMENT message.
Can be assumed to remain unchanged until there is a
new ADVERTISEMENT message.</t>
<t hangText="highly-dynamic">
MAY message.</dd>
          <dt>highly-dynamic:</dt>
          <dd>
<bcp14>MAY</bcp14> change dynamically, even between consecutive ADVERTISEMENT messages.
The spatial information provided in an ADVERTISEMENT message is simply a
snapshot of the current values at the time when the message is sent.</t>
</list>
</t> sent.</dd>
        </dl></li>
       </ul>
      </section>
      <section title="&lt;relatedTo&gt;"> numbered="true" toc="default">
        <name>&lt;relatedTo&gt;</name>
        <t>
The optional &lt;relatedTo&gt; element contains the
value of the <xref target="sec-captureID">captureID target="sec-captureID" format="default">captureID attribute</xref>
of the media capture to which the considered
media capture refers.
The media capture marked with a &lt;relatedTo&gt;
element can be be, for example example, the translation of the referred
media capture in a different language.
</t>
      </section>
      <section title="&lt;view&gt;" anchor="sec-view"> anchor="sec-view" numbered="true" toc="default">
        <name>&lt;view&gt;</name>
        <t>The &lt;view&gt; element is an optional tag describing what is
represented in the spatial area covered by a media capture.
It has been specified as a simple string with an annotation pointing to
an ad hoc defined IANA registry: registry that is defined ad hoc:
</t>

<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- VIEW ELEMENT -->
<xs:element name="view" type="xs:string">
 <xs:annotation>
  <xs:documentation>
   Acceptable values (enumerations) for this type are managed
   by IANA in the "CLUE Schema <view> registry",
   accessible at TBD-IANA. https://www.iana.org/assignments/clue.
  </xs:documentation>
 </xs:annotation>
</xs:element>
]]>
</artwork>
</figure>
]]></sourcecode>
        <t>
The current possible values, as per the CLUE framework document
<xref target="I-D.ietf-clue-framework"/>, target="RFC8845" format="default"/>, are: "room", "table",
"lectern", "individual", and "audience".
</t>
      </section>
      <section title="&lt;presentation&gt;" anchor="sec-presentation"> anchor="sec-presentation" numbered="true" toc="default">
        <name>&lt;presentation&gt;</name>
        <t>The &lt;presentation&gt; element is an optional tag used for media
captures conveying information about presentations within the
telepresence session. It has been specified as a simple string with an
annotation pointing to an ad hoc defined IANA registry: registry that is defined ad hoc:
</t>

<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- PRESENTATION ELEMENT -->
<xs:element name="presentation" type="xs:string">
 <xs:annotation>
  <xs:documentation>
   Acceptable values (enumerations) for this type are managed
   by IANA in the "CLUE Schema <presentation> registry",
   accessible at TBD-IANA. https://www.iana.org/assignments/clue.
  </xs:documentation>
 </xs:annotation>
</xs:element>
]]>
</artwork>
</figure>
]]></sourcecode>
        <t>
The current possible values, as per the CLUE framework document
<xref target="I-D.ietf-clue-framework"/>, target="RFC8845" format="default"/>, are "slides" and "images".
</t>
      </section>
      <section title="&lt;embeddedText&gt;"
anchor="sec-embedded-text"> anchor="sec-embedded-text" numbered="true" toc="default">
        <name>&lt;embeddedText&gt;</name>
        <t>
The &lt;embeddedText&gt; element is a boolean
element indicating that there is text embedded
in the media capture (e.g., in a video capture).
The language used in such an embedded textual description
is reported in the &lt;embeddedText&gt; "lang" attribute.
</t>
        <t>
The XML Schema definition of the &lt;embeddedText&gt;
element is:
</t>
<t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- EMBEDDED TEXT ELEMENT -->
<xs:element name="embeddedText">
 <xs:complexType>
  <xs:simpleContent>
   <xs:extension base="xs:boolean">
    <xs:attribute name="lang" type="xs:language"/>
   </xs:extension>
  </xs:simpleContent>
 </xs:complexType>
</xs:element>
]]>
</artwork>
</figure>
</t>
]]></sourcecode>
      </section>
      <section title="&lt;capturedPeople&gt;" anchor="sec-participantIDs"> anchor="sec-participantIDs" numbered="true" toc="default">
        <name>&lt;capturedPeople&gt;</name>
        <t>This optional element is used to indicate which
telepresence session participants
are represented in within the media captures. For each participant, a
&lt;personIDREF&gt; element is provided.</t>
        <section title="&lt;personIDREF&gt;"> numbered="true" toc="default">
          <name>&lt;personIDREF&gt;</name>
          <t>
&lt;personIDREF&gt; contains the identifier of the represented person,
i.e., the value of the related <xref target="sub-sec-participantID"> target="sub-sec-participantID" format="default">
personID attribute</xref>.
Metadata about the represented participant can be retrieved by accessing
the &lt;people&gt; list (<xref target="sec-participants"/>). target="sec-participants" format="default"/>).
</t>
        </section>
      </section>

</section><!-- media capture section -->
    </section>

    <section title="Audio captures"> numbered="true" toc="default">
      <name>Audio Captures</name>
      <t>Audio captures inherit all the features of a generic
media capture and present further audio-specific
characteristics.
The XML Schema definition of the audio
capture type is reported below:
</t>
<t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- AUDIO CAPTURE TYPE -->
<xs:complexType name="audioCaptureType">
 <xs:complexContent>
  <xs:extension base="tns:mediaCaptureType">
   <xs:sequence>
        <xs:element ref="sensitivityPattern" minOccurs="0" />
    <xs:any namespace="##other" processContents="lax" minOccurs="0"
    maxOccurs="unbounded"/>
   </xs:sequence>
   <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:extension>
 </xs:complexContent>
</xs:complexType>

]]>
</artwork>
</figure>
</t>
]]></sourcecode>
      <t>
An example of audio-specific information
that can be included is represented by the &lt;sensitivityPattern&gt;
element.
element (<xref target="sec-sensitivity-pattern"/>). target="sec-sensitivity-pattern" format="default"/>).
</t>
      <section title="&lt;sensitivityPattern&gt;"
anchor="sec-sensitivity-pattern"> anchor="sec-sensitivity-pattern" numbered="true" toc="default">
        <name>&lt;sensitivityPattern&gt;</name>
        <t>
The &lt;sensitivityPattern&gt; element is an optional field
describing the characteristics of the nominal sensitivity pattern of the
microphone capturing the audio signal. It has been specified as a simple
string with an annotation pointing to an ad hoc defined IANA registry: registry that is defined ad hoc:
</t>

<t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- SENSITIVITY PATTERN ELEMENT -->
<xs:element name="sensitivityPattern" type="xs:string">
 <xs:annotation>
  <xs:documentation>
   Acceptable values (enumerations) for this type are managed by IANA
   in the "CLUE Schema <sensitivityPattern> registry", accessible
   at TBD-IANA. https://www.iana.org/assignments/clue.
  </xs:documentation>
 </xs:annotation>
</xs:element>
]]>
</artwork>
</figure>
</t>
]]></sourcecode>
        <t>
The current possible values, as per the CLUE framework document
<xref target="I-D.ietf-clue-framework"/>, target="RFC8845" format="default"/>, are "uni", "shotgun", "omni",
"figure8", "cardioid" "cardioid", and "hyper-cardioid".
</t>
      </section>
</section><!-- audio capture -->
    </section>

    <section title="Video captures"> numbered="true" toc="default">
      <name>Video Captures</name>
      <t>Video captures, similarly to audio captures,
extend the information of a generic media capture
with video-specific features.</t>
      <t>
The XML Schema representation of the
video capture type is provided in the following:
</t>
<t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- VIDEO CAPTURE TYPE -->
<xs:complexType name="videoCaptureType">
 <xs:complexContent>
  <xs:extension base="tns:mediaCaptureType">
   <xs:sequence>
    <xs:any namespace="##other" processContents="lax" minOccurs="0"
    maxOccurs="unbounded"/>
   </xs:sequence>
   <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:extension>
 </xs:complexContent>
</xs:complexType>
]]>
</artwork>
</figure>
</t>
</section><!-- video capture -->
]]></sourcecode>
    </section>

    <section title="Text captures">
<t>Also numbered="true" toc="default">
      <name>Text Captures</name>

      <t>Similar to audio captures and video captures, text captures can be described
by extending the generic media capture information,
similarly to audio captures and video captures.</t> information.</t>
      <t>There are no known properties of a text-based media which that aren't
already covered by the generic mediaCaptureType. Text captures are hence
defined as follows:</t>
<t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- TEXT CAPTURE TYPE -->
<xs:complexType name="textCaptureType">
 <xs:complexContent>
  <xs:extension base="tns:mediaCaptureType">
  <xs:sequence>
  <xs:any namespace="##other" processContents="lax" minOccurs="0"
    maxOccurs="unbounded"/>
  </xs:sequence>
  <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:extension>
 </xs:complexContent>
</xs:complexType>

]]>
</artwork>
</figure>
</t>
]]></sourcecode>
      <t>Text captures MUST <bcp14>MUST</bcp14> be marked as non spatially definable (i.e., they
MUST
<bcp14>MUST</bcp14> present in their XML description the
<xref target="sub-sec-nonspatiallydef"> target="sub-sec-nonspatiallydef" format="default">
&lt;nonSpatiallyDefinable&gt;</xref> element set to "true").
</t>
    </section>
    <section title="Other capture types"> numbered="true" toc="default">
      <name>Other Capture Types</name>
      <t>
Other media capture types can be described by using the CLUE data model.
They can be represented by exploiting the "otherCaptureType"
type.
This media capture type is conceived to be
filled in with elements defined within extensions of the current schema,
 i.e., with
elements defined in other XML schemas
(see <xref target="sec-extension"/> target="sec-extension" format="default"/> for an example).
The otherCaptureType inherits all the features envisioned for
the abstract mediaCaptureType.
</t>
      <t>The XML Schema representation of the
otherCaptureType is the following:</t>
<t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- OTHER CAPTURE TYPE -->
<xs:complexType name="otherCaptureType">
 <xs:complexContent>
  <xs:extension base="tns:mediaCaptureType">
  <xs:sequence>
  <xs:any namespace="##other" processContents="lax" minOccurs="0"
    maxOccurs="unbounded"/>
  </xs:sequence>
  <xs:anyAttribute namespace="##other" processContents="lax"/>
  </xs:extension>
 </xs:complexContent>
</xs:complexType>

]]>
</artwork>
</figure>
</t>
]]></sourcecode>
      <t>When defining new media capture types that are going to be described
by means of the &lt;otherMediaCapture&gt; element,
spatial properties of such new media capture types SHOULD <bcp14>SHOULD</bcp14> be defined
(e.g., whether or not they are spatially definable, definable and whether or not they
should be associated with an area of capture, capture or other properties
that may be defined).</t>
    </section>
    <section title="&lt;captureScene&gt;" anchor="sec-capture-scene"> anchor="sec-capture-scene" numbered="true" toc="default">
      <name>&lt;captureScene&gt;</name>
      <t>A Media Provider organizes the available captures
in capture scenes in order to help the receiver both
in both the rendering and in the selection of the group
of captures. Capture scenes are made of media captures and
capture scene views, that which are sets of
media captures of the same media type.
Each capture scene view is an alternative
to represent completely represent a capture scene for a fixed
media type.</t>
      <t>The XML Schema representation of a &lt;captureScene&gt; element
is the following:
</t>
<t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- CAPTURE SCENE TYPE -->
<xs:complexType name="captureSceneType">
 <xs:sequence>
  <xs:element ref="description" minOccurs="0" maxOccurs="unbounded"/>
  <xs:element name="sceneInformation" type="xcard:vcardType"
  minOccurs="0"/>
  <xs:element name="sceneViews" type="sceneViewsType" minOccurs="0"/>
  <xs:any namespace="##other" processContents="lax" minOccurs="0"
  maxOccurs="unbounded"/>
 </xs:sequence>
 <xs:attribute name="sceneID" type="xs:ID" use="required"/>
 <xs:attribute name="scale" type="scaleType" use="required"/>
 <xs:anyAttribute namespace="##other" processContents="lax"/>
</xs:complexType>
]]>
</artwork>
</figure>
</t>
]]></sourcecode>
      <t>
Each capture scene is identified by a "sceneID" attribute.
The &lt;captureScene&gt; element can contain zero or more
textual &lt;description&gt; elements, defined as defined in
<xref target="sec-description"/>. target="sec-description" format="default"/>.
Besides &lt;description&gt;, there is the optional
&lt;sceneInformation&gt;
element
(<xref target="sec-scene-info" />), format="default"/>),
 which contains structured
information about the scene in the vcard vCard format, and the optional
&lt;sceneViews&gt; element
(<xref target="sec-scene-views"/>), target="sec-scene-views" format="default"/>), which is the list of
the capture scene
views.
When no &lt;sceneViews&gt; is provided, the capture scene is assumed to
be made of all the media captures which that contain the value of its sceneID
attribute in their mandatory captureSceneIDREF attribute.
</t>
      <section title="&lt;sceneInformation&gt;" anchor="sec-scene-info"> anchor="sec-scene-info" numbered="true" toc="default">
        <name>&lt;sceneInformation&gt;</name>
        <t>
The &lt;sceneInformation&gt; element contains optional information about
 the
capture scene according to the vcard vCard format, as specified in the Xcard
RFC xCard
specification <xref target="RFC6351"/>. target="RFC6351" format="default"/>.
</t>
      </section>
      <section title="&lt;sceneViews&gt;"
anchor="sec-scene-views"> anchor="sec-scene-views" numbered="true" toc="default">
        <name>&lt;sceneViews&gt;</name>
        <t>
The &lt;sceneViews&gt; element is a mandatory
field of a capture scene containing the list
of scene views.
Each scene view is represented by a &lt;sceneView&gt;
element (<xref target="sec-scene-view"/>). target="sec-scene-view" format="default"/>).
</t>
<t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- SCENE VIEWS TYPE -->
<!-- envelope of scene views of a capture scene -->
<xs:complexType name="sceneViewsType">
 <xs:sequence>
  <xs:element name="sceneView" type="sceneViewType"
  maxOccurs="unbounded"/>
 </xs:sequence>
</xs:complexType>
]]>
</artwork>
</figure>
</t>
]]></sourcecode>
      </section>
      <section title="sceneID attribute" anchor="sec-sceneID"> anchor="sec-sceneID" numbered="true" toc="default">
        <name>sceneID Attribute</name>
        <t>The sceneID attribute is a mandatory attribute
containing the identifier of the capture scene.
</t>
      </section>
      <section title="scale attribute" anchor="sec-scale"> anchor="sec-scale" numbered="true" toc="default">
        <name>scale Attribute</name>
        <t>
The scale attribute is a mandatory attribute
that specifies the scale of the coordinates
provided in the spatial
information of the media capture belonging to
the considered capture scene.
The scale attribute can assume three different values:
</t>
<t>
<list style="empty">
<t>"mm" - the
        <ul empty="true" spacing="normal"><li>
        <dl newline="false" spacing="normal">
        <dt>"mm":</dt><dd>the scale is in millimeters.
Systems which that
know their physical dimensions
(for example example, professionally
installed telepresence room systems)
should always provide such
real-world measurements.
</t>
<t>"unknown" - the measurements.</dd>
          <dt>"unknown":</dt><dd>the scale is the same for every media capture
in the capture scene scene, but the unity of measure is undefined.
Systems which that are not aware of specific
physical dimensions yet still know
relative distances should select
"unknown" in the scale attribute of the
capture scene to be described.
</t>
<t>"noscale" - there described.</dd>
          <dt>"noscale":</dt><dd>there is no common physical scale
among the media captures of the capture scene.
That means the scale could be different for each
media capture. </t>
</list>
</t>
<t>
<figure>
<artwork>
<![CDATA[ capture.</dd></dl></li>
        </ul>
<sourcecode type="xml"><![CDATA[
<!-- SCALE TYPE -->
<xs:simpleType name="scaleType">
 <xs:restriction base="xs:string">
  <xs:enumeration value="mm"/>
  <xs:enumeration value="unknown"/>
  <xs:enumeration value="noscale"/>
 </xs:restriction>
</xs:simpleType>
]]>
</artwork>
</figure>
</t>
]]></sourcecode>
      </section>
    </section>
</section><!-- capture scene section -->

    <section title="&lt;sceneView&gt;"
anchor="sec-scene-view"> anchor="sec-scene-view" numbered="true" toc="default">
      <name>&lt;sceneView&gt;</name>
      <t>
A &lt;sceneView&gt; element represents a
capture scene view, which contains a set of media
captures of the same media type describing
a capture scene.
</t>
      <t>A &lt;sceneView&gt; element is characterized as follows.
</t>
<t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- SCENE VIEW TYPE -->
<xs:complexType name="sceneViewType">
 <xs:sequence>
  <xs:element ref="description" minOccurs="0" maxOccurs="unbounded"/>
  <xs:element name="mediaCaptureIDs" type="captureIDListType"/>
 </xs:sequence>
 <xs:attribute name="sceneViewID" type="xs:ID" use="required"/>
</xs:complexType>

]]>
</artwork>
</figure>
</t>
]]></sourcecode>
      <t>
One or more optional &lt;description&gt; elements
provide human-readable information about what the scene
view contains. &lt;description&gt; is defined as already
seen in <xref target="sec-description"/>. target="sec-description" format="default"/>.
</t>
      <t>The remaining child elements are described in the
following subsections.</t>
      <section title="&lt;mediaCaptureIDs&gt;"> numbered="true" toc="default">
        <name>&lt;mediaCaptureIDs&gt;</name>
        <t>
The
&lt;mediaCaptureIDs&gt; is the list of the
identifiers of the media captures included in the
scene view.
It is an element of the captureIDListType type, which is
defined as a sequence of &lt;mediaCaptureIDREF&gt;, each
containing the identifier of a media capture
listed within the &lt;mediaCaptures&gt; element:
</t>
<t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- CAPTURE ID LIST TYPE -->
<xs:complexType name="captureIDListType">
 <xs:sequence>
  <xs:element name="mediaCaptureIDREF" type="xs:IDREF"
  maxOccurs="unbounded"/>
 </xs:sequence>
</xs:complexType>
]]>
</artwork>
</figure>
</t>
]]></sourcecode>
      </section>
      <section title="sceneViewID attribute"> numbered="true" toc="default">
        <name>sceneViewID Attribute</name>
        <t>The sceneViewID attribute is a mandatory attribute
containing the identifier of the capture scene view
represented by the &lt;sceneView&gt; element.</t>
      </section>
</section><!-- scene view section -->
    </section>
    <section title="&lt;encodingGroup&gt;"
anchor="sec-encoding-group"> anchor="sec-encoding-group" numbered="true" toc="default">
      <name>&lt;encodingGroup&gt;</name>
      <t>
The &lt;encodingGroup&gt; element represents
an encoding group, which is made by a
 set of one or more individual
 encodings and some parameters that apply
 to the group as a whole.
 Encoding groups contain references to individual encodings
 that can be applied to media captures.
 The definition of the &lt;encodingGroup&gt; element
 is the following:
</t>
<t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- ENCODING GROUP TYPE -->
<xs:complexType name="encodingGroupType">
 <xs:sequence>
  <xs:element name="maxGroupBandwidth" type="xs:unsignedLong"/>
  <xs:element name="encodingIDList" type="encodingIDListType"/>
  <xs:any namespace="##other" processContents="lax" minOccurs="0"
  maxOccurs="unbounded"/>
 </xs:sequence>
 <xs:attribute name="encodingGroupID" type="xs:ID" use="required"/>
 <xs:anyAttribute namespace="##any" processContents="lax"/>
</xs:complexType>
]]>
</artwork>
</figure>
</t>
]]></sourcecode>
      <t>
In the following, following subsections, the contained elements are further described.
</t>
      <section title="&lt;maxGroupBandwidth&gt;"> numbered="true" toc="default">
        <name>&lt;maxGroupBandwidth&gt;</name>
        <t>&lt;maxGroupBandwidth&gt; is an optional field
containing the maximum bitrate expressed in bits per second that can be
shared by the individual encodings included in the encoding group.
</t>
      </section>
      <section title="&lt;encodingIDList&gt;" anchor="sec-encodingIDList"> anchor="sec-encodingIDList" numbered="true" toc="default">
        <name>&lt;encodingIDList&gt;</name>
        <t>&lt;encodingIDList&gt; is the list
of the individual encodings grouped together in the encoding group.
Each individual encoding is represented
through its identifier contained within
an &lt;encodingID&gt; element.
</t>
<t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- ENCODING ID LIST TYPE -->
<xs:complexType name="encodingIDListType">
 <xs:sequence>
  <xs:element name="encodingID" type="xs:string"
   maxOccurs="unbounded"/>
 </xs:sequence>
</xs:complexType>
]]>
</artwork>
</figure>
</t>
]]></sourcecode>
      </section>
      <section title="encodingGroupID attribute" anchor="sec-encodingGroupID"> anchor="sec-encodingGroupID" numbered="true" toc="default">
        <name>encodingGroupID Attribute</name>
        <t>The encodingGroupID attribute contains the
identifier of the encoding group.</t>
      </section>
</section><!-- encoding group -->
    </section>

    <section title="&lt;simultaneousSet&gt;" anchor="sec-simultaneous-set"> anchor="sec-simultaneous-set" numbered="true" toc="default">
      <name>&lt;simultaneousSet&gt;</name>
      <t>&lt;simultaneousSet&gt; represents a simultaneous
transmission set, i.e., a list of captures of the same media type
that can be transmitted at the same time
by a Media Provider.
There are different simultaneous transmission sets
for each media type.
</t>
<t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- SIMULTANEOUS SET TYPE -->
<xs:complexType name="simultaneousSetType">
 <xs:sequence>
   <xs:element name="mediaCaptureIDREF" type="xs:IDREF"
   minOccurs="0" maxOccurs="unbounded"/>
   <xs:element name="sceneViewIDREF" type="xs:IDREF"
   minOccurs="0" maxOccurs="unbounded"/>
   <xs:element name="captureSceneIDREF" type="xs:IDREF"
   minOccurs="0" maxOccurs="unbounded"/>
   <xs:any namespace="##other" processContents="lax" minOccurs="0"
   maxOccurs="unbounded"/>
 </xs:sequence>
 <xs:attribute name="setID" type="xs:ID" use="required"/>
 <xs:attribute name="mediaType" type="xs:string"/>
 <xs:anyAttribute namespace="##any" processContents="lax"/>
</xs:complexType>
]]>
</artwork>
</figure>
</t>
]]></sourcecode>
      <t>
Besides the identifiers of the captures (&lt;mediaCaptureIDREF&gt;
elements), also the identifiers of capture scene views and of capture
scene
scenes can also be exploited as shortcuts
(&lt;sceneViewIDREF&gt; and &lt;captureSceneIDREF&gt; elements).
As an example, let's consider the situation where there are two capture
scene views (S1 and S7).
S1 contains captures AC11, AC12, and AC13. S7 contains captures AC71, AC71 and AC72.
Provided that AC11, AC12, AC13, AC71, and AC72 can be simultaneously sent to
the media consumer, instead of having 5 &lt;mediaCaptureIDREF&gt;
elements listed in the simultaneous set (i.e., one
&lt;mediaCaptureIDREF&gt; for AC11, one for AC12, and so on), there can
be just two &lt;sceneViewIDREF&gt; elements (one for S1 and one for S7).
</t>
      <section title="setID attribute"> numbered="true" toc="default">
        <name>setID Attribute</name>
        <t>
The "setID" attribute is a mandatory field containing the identifier of
the simultaneous set.
</t>
      </section>
      <section title="mediaType attribute"> numbered="true" toc="default">
        <name>mediaType Attribute</name>
        <t>
The "mediaType" attribute is an optional attribute containing the media
type of the
captures referenced by the simultaneous set.
</t>
        <t>When only capture scene identifiers are listed within a simultaneous
set, the media type attribute MUST <bcp14>MUST</bcp14> appear in the XML description in
order to determine which media captures can be simultaneously sent
together.
</t>
      </section>
      <section title="&lt;mediaCaptureIDREF&gt;"> numbered="true" toc="default">
        <name>&lt;mediaCaptureIDREF&gt;</name>
        <t>&lt;mediaCaptureIDREF&gt; contains the identifier of the media
capture that belongs to the simultaneous set.
</t>
      </section>
      <section title="&lt;sceneViewIDREF&gt;"> numbered="true" toc="default">
        <name>&lt;sceneViewIDREF&gt;</name>
        <t>&lt;sceneViewIDREF&gt; contains the identifier of the scene
view containing a group of captures
that are able to be sent simultaneously with the other
captures of the simultaneous set.
</t>
      </section>
      <section title="&lt;captureSceneIDREF&gt;"> numbered="true" toc="default">
        <name>&lt;captureSceneIDREF&gt;</name>
        <t>&lt;captureSceneIDREF&gt; contains the identifier of the capture
scene where all the included captures of a certain media type
are able to be sent together with the other captures of the simultaneous
set.
</t>
      </section>
</section><!-- simultaneous set section -->
    </section>

    <section title="&lt;globalView&gt;" anchor="sec-global-view"> anchor="sec-global-view" numbered="true" toc="default">
      <name>&lt;globalView&gt;</name>
      <t>&lt;globalView&gt; is a set of captures of the same media type
representing a summary of the complete Media Provider's offer.
The content of a global view is expressed
by leveraging only scene view identifiers, put within
&lt;sceneViewIDREF&gt; elements.
Each global view is identified by a unique identifier within the
"globalViewID" attribute.
</t>
<t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- GLOBAL VIEW TYPE -->
<xs:complexType name="globalViewType">
 <xs:sequence>
   <xs:element name="sceneViewIDREF" type="xs:IDREF"
    maxOccurs="unbounded"/>
   <xs:any namespace="##other" processContents="lax" minOccurs="0"
   maxOccurs="unbounded"/>
 </xs:sequence>
 <xs:attribute name="globalViewID" type="xs:ID"/>
 <xs:anyAttribute namespace="##any" processContents="lax"/>
</xs:complexType>
]]>
</artwork>
</figure>
</t>
]]></sourcecode>
    </section>
    <section title="&lt;people&gt;" anchor="sec-participants"> anchor="sec-participants" numbered="true" toc="default">
      <name>&lt;people&gt;</name>
      <t>
Information about the participants that are represented in the media
captures is conveyed via the &lt;people&gt; element.
As it can be seen from the XML Schema depicted below, for each
participant, a &lt;person&gt; element is provided.
</t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- PEOPLE TYPE -->
<xs:complexType name="peopleType">
<xs:sequence>
 <xs:element name="person" type="personType" maxOccurs="unbounded"/>
</xs:sequence>
</xs:complexType>

]]>
</artwork>
</figure>
]]></sourcecode>
      <section title="&lt;person&gt;" anchor="sub-sec-participantInfo"> anchor="sub-sec-participantInfo" numbered="true" toc="default">
        <name>&lt;person&gt;</name>
        <t>&lt;person&gt; includes all the metadata related to a person
represented within one or more media captures.
Such element provides the vcard vCard of the subject (via the
&lt;personInfo&gt; element, element; see <xref target="sub-sec-vcard"/>) target="sub-sec-vcard" format="default"/>)
and his its conference role(s) (via one or more &lt;personType&gt; elements, elements;
see <xref target="sub-sec-participantType"/>). target="sub-sec-participantType" format="default"/>).
Furthermore, it has a mandatory "personID" attribute
(<xref target="sub-sec-participantID"/>). target="sub-sec-participantID" format="default"/>).
</t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- PERSON TYPE -->
<xs:complexType name="personType">
 <xs:sequence>
  <xs:element name="personInfo" type="xcard:vcardType" maxOccurs="1"
   minOccurs="0"/>
  <xs:element ref="personType" minOccurs="0" maxOccurs="unbounded" />
  <xs:any namespace="##other" processContents="lax" minOccurs="0"
   maxOccurs="unbounded"/>
 </xs:sequence>
 <xs:attribute name="personID" type="xs:ID" use="required"/>
 <xs:anyAttribute namespace="##other" processContents="lax"/>
</xs:complexType>
]]>
</artwork>
</figure>
<section title="personID attribute" anchor="sub-sec-participantID">
]]></sourcecode>
        <section anchor="sub-sec-participantID" numbered="true" toc="default">
          <name>personID Attribute</name>
          <t>
The "personID" attribute carries the identifier of a represented person.
Such an identifier can be used to refer to the participant,
as in the &lt;capturedPeople&gt; element in the media captures
representation (<xref target="sec-participantIDs"/>). target="sec-participantIDs" format="default"/>).
</t>
        </section>
        <section title="&lt;personInfo&gt;" anchor="sub-sec-vcard"> anchor="sub-sec-vcard" numbered="true" toc="default">
          <name>&lt;personInfo&gt;</name>
          <t>The  &lt;personInfo&gt; element is the XML representation of all the
fields composing a vcard vCard as specified in the Xcard RFC xCard document
<xref target="RFC6351"/>. target="RFC6351" format="default"/>.
The vcardType is imported by the Xcard xCard XML Schema provided in Appendix
A of <xref target="I-D.ietf-ecrit-additional-data"/>. target="RFC7852" sectionFormat="of" section="A" format="default" derivedLink="https://rfc-editor.org/rfc/rfc7852#appendix-A" derivedContent="RFC7852"/>.
As such schema specifies, the &lt;fn&gt; element within &lt;vcard&gt;
is mandatory.
</t>
        </section>
        <section title="&lt;personType&gt;" anchor="sub-sec-participantType"> anchor="sub-sec-participantType" numbered="true" toc="default">
          <name>&lt;personType&gt;</name>
          <t>The value of the &lt;personType&gt; element determines the role of
the represented participant within the telepresence session
organization. It has been specified as a simple string with an
annotation pointing to an ad hoc defined IANA registry:

</t>
<figure>
<artwork>
<![CDATA[
<!-- registry that is defined ad hoc:
</t>
<sourcecode type="xml"><![CDATA[
<!-- PERSON TYPE ELEMENT -->
<xs:element name="personType" type="xs:string">
 <xs:annotation>
  <xs:documentation>
   Acceptable values (enumerations) for this type are managed
   by IANA in the "CLUE Schema <personType> registry",
   accessible at TBD-IANA. https://www.iana.org/assignments/clue.
  </xs:documentation>
 </xs:annotation>
</xs:element>

]]>
</artwork>
</figure>
]]></sourcecode>
          <t>
The current possible values, as per the CLUE framework document
<xref target="I-D.ietf-clue-framework"/>, target="RFC8845" format="default"/>, are: "presenter",
"timekeeper", "attendee", "minute taker", "translator", "chairman",
"vice-chairman", and "observer".</t>
          <t>
A participant can play more than one conference role. In that case, more
than one &lt;personType&gt; element will appear in his its description.
</t>
        </section>
      </section>
    </section>
<!-- </section>  -->

    <section title="&lt;captureEncoding&gt;" anchor="sec-capture-encoding"> anchor="sec-capture-encoding" numbered="true" toc="default">
      <name>&lt;captureEncoding&gt;</name>
      <t>A capture encoding is given from
the association of a media capture
with an individual encoding, to form a capture stream as defined in
<xref target="I-D.ietf-clue-framework"/>. target="RFC8845" format="default"/>.
Capture encodings are used within CONFIGURE messages from a Media
Consumer to a Media Provider for representing the streams desired by the
Media Consumer.
For each desired stream, the Media Consumer needs to be allowed to
specify: (i) the capture identifier of the desired capture that has been
advertised by the Media Provider; (ii) the encoding identifier of the
encoding to use, among those advertised by the Media Provider;
and (iii) optionally, in case of multi-content multicontent captures, the list of the
capture identifiers of the desired captures.
All the mentioned identifiers are intended to be included in the
ADVERTISEMENT message that the CONFIGURE message refers to.
The XML model of &lt;captureEncoding&gt; is provided in the following.
</t>
<t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- CAPTURE ENCODING TYPE -->
<xs:complexType name="captureEncodingType">
 <xs:sequence>
  <xs:element name="captureID" type="xs:string"/>
  <xs:element name="encodingID" type="xs:string"/>
  <xs:element name="configuredContent" type="contentType"
   minOccurs="0"/>
  <xs:any namespace="##other" processContents="lax" minOccurs="0"
   maxOccurs="unbounded"/>
 </xs:sequence>
 <xs:attribute name="ID" type="xs:ID" use="required"/>
 <xs:anyAttribute namespace="##any" processContents="lax"/>
</xs:complexType>

]]>
</artwork>
</figure>
</t>
]]></sourcecode>
      <section title="&lt;captureID&gt;"> numbered="true" toc="default">
        <name>&lt;captureID&gt;</name>
        <t>&lt;captureID&gt; is the mandatory element containing the identifier
of the media capture that has been encoded to
form the capture encoding.</t>
      </section>
      <section title="&lt;encodingID&gt;"> numbered="true" toc="default">
        <name>&lt;encodingID&gt;</name>
        <t>&lt;encodingID&gt; is the mandatory element containing the identifier
of the applied individual encoding.
</t>
      </section>
      <section title="&lt;configuredContent&gt;"> numbered="true" toc="default">
        <name>&lt;configuredContent&gt;</name>
        <t>&lt;configuredContent&gt; is an optional element to be used in case
of the configuration of MCC.
It contains the list of capture identifiers and capture scene view
identifiers the Media Consumer wants within the MCC.
That element is structured  as the &lt;content&gt; element used to
describe the content of an MCC.
The total number of media captures listed in the
&lt;configuredContent&gt; MUST <bcp14>MUST</bcp14> be lower than or equal to the value
carried within the &lt;maxCaptures&gt; attribute of the MCC.
</t>
      </section>
</section><!-- capture encoding section -->
    </section>

    <section title="&lt;clueInfo&gt;"> numbered="true" toc="default">
      <name>&lt;clueInfo&gt;</name>
      <t>The &lt;clueInfo&gt; element includes all the
information needed to represent the Media Provider's description of
its telepresence capabilities according to the
CLUE framework.
Indeed, it is made by:</t>
<list>
  <t>the
      <ul empty="false" spacing="normal">
        <li>the list of the available media captures
  (<xref target="sec-media-captures">&lt;mediaCaptures&gt;</xref>)</t>
  <t>the
 (see "&lt;mediaCaptures&gt;", <xref target="sec-media-captures" format="default"/>)</li>
        <li>the list of encoding groups
  (<xref target="sec-encoding-groups">&lt;encodingGroups&gt;</xref>)</t>
  <t>the
  (see "&lt;encodingGroups&gt;", <xref target="sec-encoding-groups" format="default"/>)</li>
        <li>the list of capture scenes
  (<xref target="sec-capture-scenes">&lt;captureScenes&gt;</xref>)</t>
  <t>the
  (see "&lt;captureScenes&gt;", <xref target="sec-capture-scenes" format="default"/>)</li>
        <li>the list of simultaneous transmission sets
  (<xref target="sec-simultaneous-sets">&lt;simultaneousSets&gt;</xref>)
  </t>
  <t>the
  (see "&lt;simultaneousSets&gt;", <xref target="sec-simultaneous-sets" format="default"/>)</li>
        <li>the list of global views sets
  (<xref target="sec-global-views">&lt;globalViews&gt;</xref>)</t>
  <t>meta data
  (see "&lt;globalViews&gt;", <xref target="sec-global-views" format="default"/>)</li>
        <li>metadata about the participants represented in the telepresence
  session (<xref target="sec-participants">&lt;people&gt; </xref>)</t>
</list> (see "&lt;people&gt;", <xref target="sec-participants" format="default"/>)</li>
      </ul>
      <t>
It has been conceived only for data model testing purposes and, purposes, and though
it resembles the body of an ADVERTISEMENT message, it is not actually
used in the CLUE protocol message definitions.
The telepresence capabilities descriptions compliant to
this data model specification that can be found in Sections
<xref target="sec-XML-sample"/> target="sec-XML-sample" format="counter"/> and <xref target="sec-MCC-sample"/> target="sec-MCC-sample" format="counter"/>
are provided by using the &lt;clueInfo&gt; element.
</t>
<t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<!-- CLUE INFO TYPE -->
<xs:complexType name="clueInfoType">
  <xs:sequence>
   <xs:element ref="mediaCaptures"/>
   <xs:element ref="encodingGroups"/>
   <xs:element ref="captureScenes"/>
   <xs:element ref="simultaneousSets" minOccurs="0"/>
   <xs:element ref="globalViews" minOccurs="0"/>
   <xs:element ref="people" minOccurs="0"/>
   <xs:any namespace="##other" processContents="lax" minOccurs="0"
   maxOccurs="unbounded"/>
  </xs:sequence>
  <xs:attribute name="clueInfoID" type="xs:ID" use="required"/>
  <xs:anyAttribute namespace="##other" processContents="lax"/>
</xs:complexType>

]]>
</artwork>
</figure>
</t>
]]></sourcecode>
    </section>
    <section title="XML anchor="sec-extension" numbered="true" toc="default">
      <name>XML Schema extensibility" anchor="sec-extension"> Extensibility</name>
      <t>
The telepresence data model defined in this document is
   meant to be extensible.  Extensions are accomplished by defining
   elements or attributes qualified by namespaces other than
   "urn:ietf:params:xml:ns:clue-info" and
   "urn:ietf:params:xml:ns:vcard-4.0" for use wherever the
   schema allows such extensions (i.e., where the XML Schema definition
   specifies "anyAttribute" or "anyElement").
   Elements or attributes from unknown namespaces MUST <bcp14>MUST</bcp14> be ignored.

   Extensibility was purposefully favored as much as possible based on
   expectations about custom implementations. Hence, the schema offers
   people enough flexibility as to define custom extensions, without
   losing compliance with the standard. This is achieved by leveraging
   &lt;xs:any&gt; elements and &lt;xs:anyAttribute&gt; attributes, which
   is a common approach with schemas, while still matching the UPA
   (Unique
   Unique Particle Attribution) Attribution (UPA) constraint.
</t>
      <section title="Example numbered="true" toc="default">
        <name>Example of extension"> Extension</name>
        <t>When extending the CLUE data model, a new schema
with a new namespace associated with it
needs to be specified.
</t>
        <t>
In the following, an example of extension is provided. The extension
defines a new audio capture attribute ("newAudioFeature") and
an attribute for characterizing the captures belonging to an
"otherCaptureType" defined by the user.
An XML document compliant with the extension is also included.
The XML file results are validated against the current CLUE data model
schema.
</t>
<t>
<figure>
<artwork>
<![CDATA[
<sourcecode type="xml"><![CDATA[
<?xml version="1.0" encoding="UTF-8" ?>
<xs:schema
   targetNamespace="urn:ietf:params:xml:ns:clue-info-ext"
   xmlns:tns="urn:ietf:params:xml:ns:clue-info-ext"
   xmlns:clue-ext="urn:ietf:params:xml:ns:clue-info-ext"
   xmlns:xs="http://www.w3.org/2001/XMLSchema"
   xmlns="urn:ietf:params:xml:ns:clue-info-ext"
   xmlns:xcard="urn:ietf:params:xml:ns:vcard-4.0"
   xmlns:info="urn:ietf:params:xml:ns:clue-info"
   elementFormDefault="qualified"
   attributeFormDefault="unqualified">

<!-- Import xcard xCard XML schema -->
<xs:import namespace="urn:ietf:params:xml:ns:vcard-4.0"
schemaLocation=
 "http://www.iana.org/assignments/xml-registry/schema/vcard-4.0.xsd"/>
  "https://www.iana.org/assignments/xml-registry/schema/
   vcard-4.0.xsd"/>

<!-- Import CLUE XML schema -->
<xs:import namespace="urn:ietf:params:xml:ns:clue-info"
schemaLocation="clue-data-model-schema.xsd"/>

<!-- ELEMENT DEFINITIONS -->
<xs:element name="newAudioFeature" type="xs:string"/>
<xs:element name="otherMediaCaptureTypeFeature" type="xs:string"/>

</xs:schema>
]]>
</artwork>
</figure>
</t>
<t>
<figure>
<artwork>
<![CDATA[
]]></sourcecode>

<sourcecode type="xml"><![CDATA[
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<clueInfo xmlns="urn:ietf:params:xml:ns:clue-info"
xmlns:ns2="urn:ietf:params:xml:ns:vcard-4.0"
xmlns:ns3="urn:ietf:params:xml:ns:clue-info-ext"
clueInfoID="NapoliRoom">
    <mediaCaptures>
        <mediaCapture
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:type="audioCaptureType"
        captureID="AC0"
        mediaType="audio">
            <captureSceneIDREF>CS1</captureSceneIDREF>
            <nonSpatiallyDefinable>true</nonSpatiallyDefinable>
            <individual>true</individual>
            <encGroupIDREF>EG1</encGroupIDREF>
            <ns3:newAudioFeature>newAudioFeatureValue
            </ns3:newAudioFeature>
        </mediaCapture>
        <mediaCapture
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:type="otherCaptureType"
        captureID="OMC0"
        mediaType="other media type">
            <captureSceneIDREF>CS1</captureSceneIDREF>
            <nonSpatiallyDefinable>true</nonSpatiallyDefinable>
            <encGroupIDREF>EG1</encGroupIDREF>
            <ns3:otherMediaCaptureTypeFeature>OtherValue
            </ns3:otherMediaCaptureTypeFeature>
        </mediaCapture>
    </mediaCaptures>
    <encodingGroups>
        <encodingGroup encodingGroupID="EG1">
            <maxGroupBandwidth>300000</maxGroupBandwidth>
            <encodingIDList>
                <encodingID>ENC4</encodingID>
                <encodingID>ENC5</encodingID>
            </encodingIDList>
        </encodingGroup>
    </encodingGroups>
    <captureScenes>
        <captureScene scale="unknown" sceneID="CS1"/>
    </captureScenes>
</clueInfo>
]]>
</artwork>
</figure>
</t>
]]></sourcecode>
      </section>
    </section>
    <section title="Security considerations" anchor="sec:security"> anchor="sec_security" numbered="true" toc="default">
      <name>Security Considerations</name>
      <t>
 This document defines an XML Schema data model for telepresence
 scenarios.
 The modeled information is identified in the CLUE framework
 as necessary in order to enable a full-fledged
 media stream negotiation and rendering.
 Indeed, the XML elements herein defined are used within
 CLUE protocol messages to describe
 both the media streams representing the Media Provider's telepresence
 offer and the desired selection requested by the Media Consumer.
 Security concerns described in
 <xref target="I-D.ietf-clue-framework"/>, Section 15, target="RFC8845" sectionFormat="comma" section="15"/> apply to this
 document.
</t>
      <t>

Data model information carried within CLUE messages SHOULD <bcp14>SHOULD</bcp14>
be accessed only by authenticated endpoints.
Indeed, authenticated access is strongly advisable, especially if you
convey information about individuals (&lt;personalInfo&gt;) and/or
scenes (&lt;sceneInformation&gt;).
There might be more exceptions, depending on the level of criticality
that is associated with the setup and configuration of a specific
session. In principle, one might even decide that no protection at all
is needed for a particular session; here is why authentication
has not been identified as a mandatory requirement.

</t>
      <t>
Going deeper into details, some information published by the Media
Provider might reveal sensitive data about who and what is represented
in the transmitted streams.
The vCard included in the &lt;personInfo&gt;
elements (<xref target="sub-sec-participantInfo"/>) target="sub-sec-participantInfo" format="default"/>)
mandatorily contains the identity of the represented person.
Optionally
Optionally, vCards can also carry the person's contact addresses,
together with his/her their photo and other personal data. Similar
privacy-critical information can be conveyed by means of
&lt;sceneInformation&gt; elements (<xref target="sec-scene-info"/>) target="sec-scene-info" format="default"/>)
describing the capture scenes.
The &lt;description&gt; elements (<xref target="sec-description"/>) target="sec-description" format="default"/>) also
can specify details about the content of media captures, capture scenes scenes,
and scene views that should be protected.
</t>
      <t>
Integrity attacks to the data model information encapsulated
in CLUE messages can  invalidate the success of the telepresence
session's setup by misleading the Media Consumer's and Media Provider's
interpretation of the offered and desired media streams.
</t><t>
</t>
      <t>
The assurance of the authenticated access and of the integrity of the
data model information is up to the involved transport mechanisms,
namely the CLUE protocol
<xref target="I-D.ietf-clue-protocol"/> target="RFC8847" format="default"/>
and the CLUE data channel <xref target="I-D.ietf-clue-datachannel"/>. target="RFC8850" format="default"/>.
</t>
      <t>
XML parsers need to be robust with respect to malformed documents.
Reading malformed documents from unknown or untrusted sources could
result in an attacker gaining privileges of the user running the XML
parser. In an extreme situation, the entire machine could be
compromised.
</t>
    </section>
    <section title="IANA considerations">
 <t> numbered="true" toc="default">
      <name>IANA Considerations</name>

<!--[rfced] Fyi, we removed 'MIME' from the IANA section per guidance
on the IANA website, which indicates that 'MIME' is now
obsolete. If you have any concerns or objections, please let us
know.

One example

Original:
   This document registers a new XML namespace, a new XML schema, the
   MIME type for the schema and four new registries associated,
   respectively, with acceptable &lt;view&gt;, &lt;presentation&gt;,
 &lt;sensitivityPattern&gt; <view>, <presentation>,
   <sensitivityPattern> and &lt;personType&gt; <personType> values.
 </t>

<section title="XML namespace registration">
<t>
</t>

Current:
   This section document registers a new XML namespace:
<t> namespace, a new XML schema, the
   media type for the schema, and four new registries associated,
   respectively, with acceptable <view>, <presentation>,
   <sensitivityPattern>, and <personType> values.
-->
      <t>
URI: urn:ietf:params:xml:ns:clue-info
 This document registers a new XML namespace, a new XML schema, the media
 type for the schema, and four new registries associated, respectively,
 with acceptable &lt;view&gt;, &lt;presentation&gt;,
 &lt;sensitivityPattern&gt;, and &lt;personType&gt; values.
      </t>
<t>
Registrant Contact: IETF
      <section numbered="true" toc="default">
        <name>XML Namespace Registration</name>

<dl newline="false" spacing="normal">
<dt>URI:</dt><dd>urn:ietf:params:xml:ns:clue-info</dd>
<dt>Registrant Contact:</dt><dd>IETF CLUE Working Group &lt;clue@ietf.org&gt;,
Roberta Presta &lt;roberta.presta@unina.it&gt;
</t>
<t>XML:</t>
<figure>
<artwork>
<![CDATA[
BEGIN &lt;roberta.presta@unina.it&gt;</dd>
   <dt>XML:</dt><dd></dd>
</dl>
<sourcecode type="xml" markers="true"><![CDATA[
<?xml version="1.0"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML Basic 1.0//EN"
 "http://www.w3.org/TR/xhtml-basic/xhtml-basic10.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
 <head>
  <meta http-equiv="content-type"
        content="text/html;charset=iso-8859-1"/>
  <title> CLUE
  <title>CLUE Data Model Namespace</title>
 </head>
 <body>
  <h1>Namespace for CLUE Data Model</h1>
  <h2>urn:ietf:params:xml:ns:clue-info</h2>
  <p>See
   <a href="http://www.rfc-editor.org/rfc/rfcXXXX.txt"> RFC XXXX</a>.
   <!--[[NOTE TO IANA/RFC-EDITOR: Please update RFC URL
    and replace XXXX with the RFC number for this specification.]]--> href="https://www.rfc-editor.org/rfc/rfc8846.txt">RFC 8846</a>.
  </p>
 </body>
</html>

END
]]>
</artwork>
</figure>
 </t>
]]></sourcecode>

      </section>
      <section title="XML numbered="true" toc="default">
        <name>XML Schema registration"> Registration</name>
        <t>
This section registers an XML schema per the guidelines in
<xref target="RFC3688"/>. target="RFC3688" format="default"/>.
</t>

<t>
URI:
urn:ietf:params:xml:schema:clue-info
</t>
<t>
Registrant Contact:
CLUE working group
<dl newline="false" spacing="normal">
<dt>URI:</dt><dd>urn:ietf:params:xml:schema:clue-info</dd>

<dt>Registrant Contact:</dt>
<dd>CLUE Working Group (clue@ietf.org),
Roberta Presta (roberta.presta@unina.it).
</t>
<t>
Schema:
The (roberta.presta@unina.it).</dd>

<dt>Schema:</dt>
<dd>The XML for this schema can be found as the in its entirety of in
<xref target="sec-schema"/> target="sec-schema" format="default"/> of this document.
</t> document.</dd>
</dl>
      </section>
      <section title='MIME Media numbered="true" toc="default">
        <name>Media Type Registration for
	"application/clue_info+xml"'> "application/clue_info+xml"</name>
        <t>This section registers the
<spanx style="verb">application/clue_info+xml</spanx> MIME "application/clue_info+xml" media type.
</t>

<t>To:  ietf-types@iana.org</t>
<t>Subject:
Registration
<dl newline="false" spacing="normal">
        <dt>To:</dt><dd>ietf-types@iana.org</dd>
        <dt>Subject:</dt><dd>Registration of MIME media type application/clue_info+xml
</t>
<t>MIME media type name:
application</t>
<t>MIME subtype name:  clue_info+xml</t>
<t>Required parameters:  (none)</t>
<t>Optional parameters:  charset <vspace/> application/clue_info+xml</dd>
        <dt>Type name:</dt><dd>application</dd>
        <dt>Subtype name:</dt><dd>clue_info+xml</dd>
        <dt>Required parameters:</dt><dd>(none)</dd>
        <dt>Optional parameters:</dt><dd>charset
Same as the charset parameter of "application/xml" as specified in
<xref target="RFC7303"/>, Section 3.2.
</t>
<t>Encoding considerations:
Same target="RFC7303" sectionFormat="comma" section="3.2"/>.</dd>
        <dt>Encoding considerations:</dt><dd>Same as the encoding considerations of
"application/xml" as specified in <xref target="RFC7303"/>, Section 3.2.
</t>
<t>Security considerations:
This target="RFC7303" sectionFormat="comma" section="3.2"/>.
</dd>
        <dt>Security considerations:</dt><dd>This content type is designed to carry
 data related to telepresence information.  Some of the data
could be considered private.  This media type does not provide any
protection and thus other mechanisms such as those described in
<xref target="sec:security"/> target="sec_security" format="default"/>
are required to protect the data.  This media type does
not contain executable content.
</t>
<t>Interoperability considerations:  None.
</t>
<t>Published specification:
RFC XXXX
[[NOTE TO IANA/RFC-EDITOR:
Please replace XXXX with the RFC number for this specification.]]
</t>
<t>Applications
</dd>
        <dt>Interoperability considerations:</dt><dd>None.</dd>
        <dt>Published specification:</dt><dd>RFC 8846</dd>
        <dt>Applications that use this media type:  CLUE-capable type:</dt><dd>CLUE-capable telepresence
systems.
</t>
<t>Additional Information:
Magic Number(s): (none), <vspace/>
File extension(s): .clue, <vspace/>
Macintosh
systems.</dd>

<dt>Additional Information:</dt>
<dd>
<t><br/></t>
<dl newline="false" spacing="compact">
<dt>Magic Number(s):</dt><dd>none</dd>
<dt>File extension(s):</dt><dd>.clue</dd>
<dt>Macintosh File Type Code(s): TEXT. <vspace/>
</t>
<t>Person Code(s):</dt><dd>TEXT</dd>
</dl>
</dd>

        <dt>Person &amp; email address to contact for further information:
Roberta
	information:</dt><dd>Roberta Presta (roberta.presta@unina.it).
</t>
<t>Intended usage:
LIMITED USE
</t>
<t>Author/Change controller:
The IETF
</t>
<t>Other information:
This (roberta.presta@unina.it).</dd>
        <dt>Intended usage:</dt><dd>LIMITED USE</dd>
        <dt>Author/Change controller:</dt><dd>The IETF</dd>
        <dt>Other information:</dt><dd>This media type is a specialization of
application/xml
"application/xml" <xref target="RFC7303"/>, target="RFC7303" format="default"/>, and many of the considerations
described there also apply to application/clue_info+xml.
</t> "application/clue_info+xml".
</dd></dl>
      </section>
      <section title="Registry numbered="true" toc="default">
        <name>Registry for acceptable Acceptable &lt;view&gt; values"> Values</name>
        <t>
IANA is requested to create has created a registry of acceptable values for the the
&lt;view&gt; tag as defined in <xref target="sec-view"/>. target="sec-view" format="default"/>.
The initial values for this registry are "room", "table", "lectern",
"individual", and "audience".
</t>
        <t>

<!-- [rfced] RFC 5226 has been obsoleted by RFC 8126.  We have replaced RFC
5226 with RFC 8126 accordingly. Please let us know any objections.
-->

New values are assigned by Expert Review per <xref target="RFC5226"/>. target="RFC8126" format="default"/>.
This reviewer will ensure that the requested registry entry conforms to
the prescribed formatting.
</t>

<t>
IANA is further requested to update this draft with the URL to the new
registry in <xref target="sec-view"/>, marked as "TBD-IANA".
</t>
      </section>
      <section title="Registry numbered="true" toc="default">
        <name>Registry for acceptable Acceptable &lt;presentation&gt; values"> Values</name>
        <t>
IANA is requested to create has created a registry of acceptable values for the the
&lt;presentation&gt; tag as defined in
<xref target="sec-presentation"/>. target="sec-presentation" format="default"/>.
The initial values for this registry are "slides" and "images".
</t>
        <t>
New values are assigned by Expert Review per <xref target="RFC5226"/>. target="RFC8126" format="default"/>.
This reviewer will ensure that the requested registry entry conforms to
the prescribed formatting.
</t>

<t>
IANA is further requested to update this draft with the URL to the new
registry in <xref target="sec-presentation"/>, marked as "TBD-IANA".
</t>
      </section>
      <section title="Registry numbered="true" toc="default">
        <name>Registry for acceptable Acceptable &lt;sensitivityPattern&gt;
	values"> Values</name>
        <t>
IANA is requested to create has created a registry of acceptable values for the the
&lt;sensitivityPattern&gt; tag as defined in
<xref target="sec-sensitivity-pattern"/>. target="sec-sensitivity-pattern" format="default"/>.
The initial values for this registry are "uni", "shotgun", "omni",
"figure8", "cardioid" "cardioid", and "hyper-cardioid".
</t>
        <t>
New values are assigned by Expert Review per <xref target="RFC5226"/>. target="RFC8126" format="default"/>.
This reviewer will ensure that the requested registry entry conforms to
the prescribed formatting.
</t>

<t>
IANA is further requested to update this draft with the URL to the new
registry in <xref target="sec-sensitivity-pattern"/>, marked as "TBD-IANA".
</t>
      </section>
      <section title="Registry numbered="true" toc="default">
        <name>Registry for acceptable Acceptable &lt;personType&gt; values"> Values</name>
        <t>
IANA is requested to create has created a registry of acceptable values for the the
&lt;personType&gt; tag as defined in
<xref target="sub-sec-participantType"/>. target="sub-sec-participantType" format="default"/>.
The initial values for this registry are "presenter",
"timekeeper", "attendee", "minute taker", "translator", "chairman",
"vice-chairman", and "observer".
</t>
        <t>
New values are assigned by Expert Review per <xref target="RFC5226"/>. target="RFC8126" format="default"/>.
This reviewer will ensure that the requested registry entry conforms to
the prescribed formatting.
</t>

<t>
IANA is further requested to update this draft with the URL to the new
registry in <xref target="sub-sec-participantType"/>, marked as
"TBD-IANA".
</t>
      </section>
    </section>
    <section title="Sample anchor="sec-XML-sample" numbered="true" toc="default">
      <name>Sample XML file" anchor="sec-XML-sample"> File</name>
      <t>The following XML document represents a schema compliant schema-compliant example
  of a CLUE telepresence scenario.
  Taking inspiration from the examples described in
  the framework draft (<xref target="I-D.ietf-clue-framework"/>),
  it is provided specification <xref target="RFC8845" format="default"/>,
  the XML representation of an endpoint-style Media
  Provider's ADVERTISEMENT.
  </t><t> ADVERTISEMENT is provided.
      </t>
      <t>
  There are three cameras, where the central one is also capable of
  capturing a zoomed-out
  view of the overall telepresence room.
  Besides the three video captures coming from the cameras,
  the Media Provider makes available a further multi-content multicontent capture of
  the loudest
  segment of the room,
  obtained by switching the video source across the three cameras.
  For the sake of simplicity, only one audio capture is advertised for
  the audio of the whole room.</t>
      <t>
  The three cameras are placed in front of three participants
  (Alice, Bob Bob, and Ciccio),
  whose vcard vCard and conference role details are also provided.
      </t>
      <t>
  Media captures are arranged into four capture scene views:
      </t>
 <t>
   <list style="numbers">
   <t>(VC0,
      <ol spacing="normal" type="1">
        <li>(VC0, VC1, VC2) - left, center center, and right camera video captures
   </t>
   <t>(VC3)
   </li>
        <li>(VC3) - video capture associated with loudest room segment</t>
   <t>(VC4) segment</li>
        <li>(VC4) - video capture zoomed out zoomed-out view of all people in the room
   </t>
   <t>(AC0)
   </li>
        <li>(AC0) - main audio</t>
   </list>
</t> audio</li>
      </ol>
      <t>
  There are two encoding groups: (i) EG0, for video encodings, and (ii)
  EG1, for audio encodings.
      </t>
      <t>As to the simultaneous sets, VC1 and VC4 cannot be transmitted
    simultaneously
  since they are captured by the same device, i.e., the central camera
   (VC4 is a zoomed-out view while
  VC1 is a focused view of the front participant).
  On the other hand, VC3 and VC4 cannot be simultaneous either,
  since VC3, the loudest segment of the room,
  might be at a certain point in time focusing on the central
  part of the room, i.e., the same as VC1.
  The simultaneous sets would then be the following:
  <list style="hanging">
  <t hangText="SS1">
  	made
      </t>
      <ul empty="true">
	<li>
	  <dl newline="false" spacing="normal">
            <dt>SS1:</dt>
            <dd>made by VC3 and all the captures in the first capture scene view
  	(VC0,VC1,VC2);
  </t>
  <t hangText="SS2">
    made (VC0,VC1,and VC2)
	    </dd>

            <dt>SS2:</dt>
            <dd>made by  VC0, VC2, and VC4
  </t>
  </list>
  </t>

<figure>
	<artwork>

		<![CDATA[
	    </dd>
	  </dl>
	</li>
      </ul>

<sourcecode type="xml"><![CDATA[
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<clueInfo xmlns="urn:ietf:params:xml:ns:clue-info"
          xmlns:ns2="urn:ietf:params:xml:ns:vcard-4.0"
          clueInfoID="NapoliRoom">
    <mediaCaptures>
        <mediaCapture
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:type="audioCaptureType" captureID="AC0"
              mediaType="audio">
            <captureSceneIDREF>CS1</captureSceneIDREF>
            <spatialInformation>
                <captureOrigin>
                        <capturePoint>
                        <x>0.0</x>
                        <y>0.0</y>
                        <z>10.0</z>
                    </capturePoint>
                    <lineOfCapturePoint>
                        <x>0.0</x>
                        <y>1.0</y>
                        <z>10.0</z>
                    </lineOfCapturePoint>
                </captureOrigin>
            </spatialInformation>
            <individual>true</individual>
            <encGroupIDREF>EG1</encGroupIDREF>
            <description lang="en">main audio from the room
            </description>
            <priority>1</priority>
            <lang>it</lang>
            <mobility>static</mobility>
            <view>room</view>
            <capturedPeople>
                <personIDREF>alice</personIDREF>
                <personIDREF>bob</personIDREF>
                <personIDREF>ciccio</personIDREF>
            </capturedPeople>
        </mediaCapture>
        <mediaCapture
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:type="videoCaptureType" captureID="VC0"
              mediaType="video">
            <captureSceneIDREF>CS1</captureSceneIDREF>
            <spatialInformation>
                <captureOrigin>
                        <capturePoint>
                        <x>-2.0</x>
                        <y>0.0</y>
                        <z>10.0</z>
                    </capturePoint>
                </captureOrigin>
                <captureArea>
                        <bottomLeft>
                                <x>-3.0</x>
                        <y>20.0</y>
                        <z>9.0</z>
                        </bottomLeft>
                        <bottomRight>
                                <x>-1.0</x>
                        <y>20.0</y>
                        <z>9.0</z>
                        </bottomRight>
                        <topLeft>
                                <x>-3.0</x>
                        <y>20.0</y>
                        <z>11.0</z>
                        </topLeft>
                        <topRight>
                                <x>-1.0</x>
                        <y>20.0</y>
                        <z>11.0</z>
                        </topRight>
                </captureArea>
            </spatialInformation>
            <individual>true</individual>
            <encGroupIDREF>EG0</encGroupIDREF>
            <description lang="en">left camera video capture
            </description>
            <priority>1</priority>
            <lang>it</lang>
            <mobility>static</mobility>
            <view>individual</view>
            <capturedPeople>
                <personIDREF>ciccio</personIDREF>
            </capturedPeople>
        </mediaCapture>
        <mediaCapture
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:type="videoCaptureType" captureID="VC1"
              mediaType="video">
            <captureSceneIDREF>CS1</captureSceneIDREF>
            <spatialInformation>
                <captureOrigin>
                        <capturePoint>
                        <x>0.0</x>
                        <y>0.0</y>
                        <z>10.0</z>
                    </capturePoint>
                </captureOrigin>
                <captureArea>
                        <bottomLeft>
                                <x>-1.0</x>
                        <y>20.0</y>
                        <z>9.0</z>
                        </bottomLeft>
                        <bottomRight>
                                <x>1.0</x>
                        <y>20.0</y>
                        <z>9.0</z>
                        </bottomRight>
                        <topLeft>
                                <x>-1.0</x>
                        <y>20.0</y>
                        <z>11.0</z>
                        </topLeft>
                        <topRight>
                                <x>1.0</x>
                        <y>20.0</y>
                        <z>11.0</z>
                        </topRight>
                </captureArea>
            </spatialInformation>
            <individual>true</individual>
            <encGroupIDREF>EG0</encGroupIDREF>
            <description lang="en">central camera video capture
            </description>
            <priority>1</priority>
            <lang>it</lang>
            <mobility>static</mobility>
            <view>individual</view>
            <capturedPeople>
                <personIDREF>alice</personIDREF>
            </capturedPeople>
        </mediaCapture>
        <mediaCapture
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:type="videoCaptureType" captureID="VC2"
              mediaType="video">
            <captureSceneIDREF>CS1</captureSceneIDREF>
            <spatialInformation>
                <captureOrigin>
                        <capturePoint>
                        <x>2.0</x>
                        <y>0.0</y>
                        <z>10.0</z>
                    </capturePoint>
                </captureOrigin>
                <captureArea>
                        <bottomLeft>
                                <x>1.0</x>
                        <y>20.0</y>
                        <z>9.0</z>
                        </bottomLeft>
                        <bottomRight>
                                <x>3.0</x>
                        <y>20.0</y>
                        <z>9.0</z>
                        </bottomRight>
                        <topLeft>
                                <x>1.0</x>
                        <y>20.0</y>
                        <z>11.0</z>
                        </topLeft>
                        <topRight>
                                <x>3.0</x>
                        <y>20.0</y>
                        <z>11.0</z>
                        </topRight>
                </captureArea>
            </spatialInformation>
            <individual>true</individual>
            <encGroupIDREF>EG0</encGroupIDREF>
            <description lang="en">right camera video capture
            </description>
            <priority>1</priority>
            <lang>it</lang>
            <mobility>static</mobility>
            <view>individual</view>
            <capturedPeople>
                <personIDREF>bob</personIDREF>
            </capturedPeople>
        </mediaCapture>
        <mediaCapture
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:type="videoCaptureType" captureID="VC3"
              mediaType="video">
            <captureSceneIDREF>CS1</captureSceneIDREF>
            <spatialInformation>
                <captureArea>
                        <bottomLeft>
                                <x>-3.0</x>
                        <y>20.0</y>
                        <z>9.0</z>
                        </bottomLeft>
                        <bottomRight>
                                <x>3.0</x>
                        <y>20.0</y>
                        <z>9.0</z>
                        </bottomRight>
                        <topLeft>
                                <x>-3.0</x>
                        <y>20.0</y>
                        <z>11.0</z>
                        </topLeft>
                        <topRight>
                                <x>3.0</x>
                        <y>20.0</y>
                        <z>11.0</z>
                        </topRight>
                </captureArea>
            </spatialInformation>
            <content>
                <sceneViewIDREF>SE1</sceneViewIDREF>
            </content>
            <policy>SoundLevel:0</policy>
            <encGroupIDREF>EG0</encGroupIDREF>
            <description lang="en">loudest room segment</description>
            <priority>2</priority>
            <lang>it</lang>
            <mobility>static</mobility>
            <view>individual</view>
        </mediaCapture>
        <mediaCapture
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:type="videoCaptureType" captureID="VC4"
              mediaType="video">
            <captureSceneIDREF>CS1</captureSceneIDREF>
            <spatialInformation>
                <captureOrigin>
                        <capturePoint>
                        <x>0.0</x>
                        <y>0.0</y>
                        <z>10.0</z>
                    </capturePoint>
                </captureOrigin>
                <captureArea>
                        <bottomLeft>
                                <x>-3.0</x>
                        <y>20.0</y>
                        <z>7.0</z>
                        </bottomLeft>
                        <bottomRight>
                                <x>3.0</x>
                        <y>20.0</y>
                        <z>7.0</z>
                        </bottomRight>
                        <topLeft>
                                <x>-3.0</x>
                        <y>20.0</y>
                        <z>13.0</z>
                        </topLeft>
                        <topRight>
                                <x>3.0</x>
                        <y>20.0</y>
                        <z>13.0</z>
                        </topRight>
                </captureArea>
            </spatialInformation>
            <individual>true</individual>
            <encGroupIDREF>EG0</encGroupIDREF>
            <description lang="en">zoomed out lang="en">zoomed-out view of all people
            in the room</description>
            <priority>2</priority>
            <lang>it</lang>
            <mobility>static</mobility>
            <view>room</view>
            <capturedPeople>
                <personIDREF>alice</personIDREF>
                <personIDREF>bob</personIDREF>
                <personIDREF>ciccio</personIDREF>
            </capturedPeople>
        </mediaCapture>
    </mediaCaptures>
    <encodingGroups>
        <encodingGroup encodingGroupID="EG0">
            <maxGroupBandwidth>600000</maxGroupBandwidth>
            <encodingIDList>
                <encodingID>ENC1</encodingID>
                <encodingID>ENC2</encodingID>
                <encodingID>ENC3</encodingID>
            </encodingIDList>
        </encodingGroup>
        <encodingGroup encodingGroupID="EG1">
            <maxGroupBandwidth>300000</maxGroupBandwidth>
            <encodingIDList>
                <encodingID>ENC4</encodingID>
                <encodingID>ENC5</encodingID>
            </encodingIDList>
        </encodingGroup>
    </encodingGroups>
    <captureScenes>
        <captureScene scale="unknown" sceneID="CS1">
            <sceneViews>
                <sceneView sceneViewID="SE1">
                    <mediaCaptureIDs>
                        <mediaCaptureIDREF>VC0</mediaCaptureIDREF>
                        <mediaCaptureIDREF>VC1</mediaCaptureIDREF>
                        <mediaCaptureIDREF>VC2</mediaCaptureIDREF>
                    </mediaCaptureIDs>
                </sceneView>
                <sceneView sceneViewID="SE2">
                    <mediaCaptureIDs>
                        <mediaCaptureIDREF>VC3</mediaCaptureIDREF>
                    </mediaCaptureIDs>
                </sceneView>
                <sceneView sceneViewID="SE3">
                    <mediaCaptureIDs>
                        <mediaCaptureIDREF>VC4</mediaCaptureIDREF>
                    </mediaCaptureIDs>
                </sceneView>
                <sceneView sceneViewID="SE4">
                    <mediaCaptureIDs>
                        <mediaCaptureIDREF>AC0</mediaCaptureIDREF>
                    </mediaCaptureIDs>
                </sceneView>
            </sceneViews>
        </captureScene>
    </captureScenes>
    <simultaneousSets>
        <simultaneousSet setID="SS1">
            <mediaCaptureIDREF>VC3</mediaCaptureIDREF>
            <sceneViewIDREF>SE1</sceneViewIDREF>
        </simultaneousSet>
        <simultaneousSet setID="SS2">
            <mediaCaptureIDREF>VC0</mediaCaptureIDREF>
            <mediaCaptureIDREF>VC2</mediaCaptureIDREF>
            <mediaCaptureIDREF>VC4</mediaCaptureIDREF>
        </simultaneousSet>
    </simultaneousSets>
    <people>
        <person personID="bob">
            <personInfo>
                <ns2:fn>
                    <ns2:text>Bob</ns2:text>
                </ns2:fn>
            </personInfo>
            <personType>minute taker</personType>
        </person>
        <person personID="alice">
            <personInfo>
                <ns2:fn>
                    <ns2:text>Alice</ns2:text>
                </ns2:fn>
            </personInfo>
            <personType>presenter</personType>
        </person>
        <person personID="ciccio">
            <personInfo>
                <ns2:fn>
                    <ns2:text>Ciccio</ns2:text>
                </ns2:fn>
            </personInfo>
            <personType>chairman</personType>
            <personType>timekeeper</personType>
        </person>
    </people>
</clueInfo>

]]>
</artwork>
</figure>
]]></sourcecode>
    </section>
    <section title="MCC example" anchor="sec-MCC-sample"> anchor="sec-MCC-sample" numbered="true" toc="default">
      <name>MCC Example</name>
      <t>

Enhancing the scenario presented in the previous example, the Media
Provider is able to advertise a composed capture VC7 made by a big
picture representing the current speaker (VC3) and two
picture-in-picture boxes representing the previous speakers (the
previous one -VC5- one, VC5, and the oldest one -VC6). one, VC6).
The provider does not want to instantiate and send VC5 and VC6, so it
does not associate any encoding group with them. Their XML
representations are provided for enabling the description of VC7.
</t>

<!-- [rfced] Section 10.6:  We find "penultimate loudest room segment"
and "last but two loudest room segment" difficult to follow.  If
the suggested text is not correct, please clarify.
This pertains to RFC-to-be 8847 (draft-ietf-clue-protocol) as well.

Original:
<policy>SoundLevel:1</policy>
<description lang="en">penultimate loudest room segment
</description>
...
<policy>SoundLevel:2</policy>
<description lang="en">last but two loudest room segment
</description>

Perhaps:
<policy>SoundLevel:1</policy>
<description lang="en">previous loudest room segment per the
most recent iteration of the sound level detection algorithm
</description>
...
<policy>SoundLevel:2</policy>
<description lang="en">previous loudest room segment per the
second most recent iteration of the sound level detection
algorithm
</description> -->

      <t>A possible description for that scenario could be the following:</t>
<figure>
	<artwork>

		<![CDATA[
<sourcecode type="xml"><![CDATA[
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<clueInfo xmlns="urn:ietf:params:xml:ns:clue-info"
xmlns:ns2="urn:ietf:params:xml:ns:vcard-4.0" clueInfoID="NapoliRoom">
    <mediaCaptures>
        <mediaCapture
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:type="audioCaptureType" captureID="AC0"
              mediaType="audio">
            <captureSceneIDREF>CS1</captureSceneIDREF>
            <spatialInformation>
                <captureOrigin>
                        <capturePoint>
                        <x>0.0</x>
                        <y>0.0</y>
                        <z>10.0</z>
                    </capturePoint>
                    <lineOfCapturePoint>
                        <x>0.0</x>
                        <y>1.0</y>
                        <z>10.0</z>
                    </lineOfCapturePoint>
                </captureOrigin>
            </spatialInformation>
            <individual>true</individual>
            <encGroupIDREF>EG1</encGroupIDREF>
            <description lang="en">main audio from the room
            </description>
            <priority>1</priority>
            <lang>it</lang>
            <mobility>static</mobility>
            <view>room</view>
            <capturedPeople>
                <personIDREF>alice</personIDREF>
                <personIDREF>bob</personIDREF>
                <personIDREF>ciccio</personIDREF>
            </capturedPeople>
        </mediaCapture>
        <mediaCapture
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:type="videoCaptureType" captureID="VC0"
              mediaType="video">
            <captureSceneIDREF>CS1</captureSceneIDREF>
            <spatialInformation>
                <captureOrigin>
                        <capturePoint>
                        <x>0.5</x>
                        <y>1.0</y>
                        <z>0.5</z>
                    </capturePoint>
                    <lineOfCapturePoint>
                        <x>0.5</x>
                        <y>0.0</y>
                        <z>0.5</z>
                    </lineOfCapturePoint>
                </captureOrigin>
            </spatialInformation>
            <individual>true</individual>
            <encGroupIDREF>EG0</encGroupIDREF>
            <description lang="en">left camera video capture
            </description>
            <priority>1</priority>
            <lang>it</lang>
            <mobility>static</mobility>
            <view>individual</view>
            <capturedPeople>
                <personIDREF>ciccio</personIDREF>
            </capturedPeople>
        </mediaCapture>
        <mediaCapture
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:type="videoCaptureType" captureID="VC1"
              mediaType="video">
            <captureSceneIDREF>CS1</captureSceneIDREF>
            <spatialInformation>
                <captureOrigin>
                        <capturePoint>
                        <x>0.0</x>
                        <y>0.0</y>
                        <z>10.0</z>
                    </capturePoint>
                </captureOrigin>
                <captureArea>
                        <bottomLeft>
                                <x>-1.0</x>
                        <y>20.0</y>
                        <z>9.0</z>
                        </bottomLeft>
                        <bottomRight>
                                <x>1.0</x>
                        <y>20.0</y>
                        <z>9.0</z>
                        </bottomRight>
                        <topLeft>
                                <x>-1.0</x>
                        <y>20.0</y>
                        <z>11.0</z>
                        </topLeft>
                        <topRight>
                                <x>1.0</x>
                        <y>20.0</y>
                        <z>11.0</z>
                        </topRight>
                </captureArea>
            </spatialInformation>
            <individual>true</individual>
            <encGroupIDREF>EG0</encGroupIDREF>
            <description lang="en">central camera video capture
            </description>
            <priority>1</priority>
            <lang>it</lang>
            <mobility>static</mobility>
            <view>individual</view>
            <capturedPeople>
                <personIDREF>alice</personIDREF>
            </capturedPeople>
        </mediaCapture>
        <mediaCapture
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:type="videoCaptureType" captureID="VC2"
              mediaType="video">
            <captureSceneIDREF>CS1</captureSceneIDREF>
            <spatialInformation>
                <captureOrigin>
                        <capturePoint>
                        <x>2.0</x>
                        <y>0.0</y>
                        <z>10.0</z>
                    </capturePoint>
                </captureOrigin>
                <captureArea>
                        <bottomLeft>
                                <x>1.0</x>
                        <y>20.0</y>
                        <z>9.0</z>
                        </bottomLeft>
                        <bottomRight>
                                <x>3.0</x>
                        <y>20.0</y>
                        <z>9.0</z>
                        </bottomRight>
                        <topLeft>
                                <x>1.0</x>
                        <y>20.0</y>
                        <z>11.0</z>
                        </topLeft>
                        <topRight>
                                <x>3.0</x>
                        <y>20.0</y>
                        <z>11.0</z>
                        </topRight>
                </captureArea>
            </spatialInformation>
            <individual>true</individual>
            <encGroupIDREF>EG0</encGroupIDREF>
            <description lang="en">right camera video capture
            </description>
            <priority>1</priority>
            <lang>it</lang>
            <mobility>static</mobility>
            <view>individual</view>
            <capturedPeople>
                <personIDREF>bob</personIDREF>
            </capturedPeople>
        </mediaCapture>
        <mediaCapture
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:type="videoCaptureType" captureID="VC3"
              mediaType="video">
            <captureSceneIDREF>CS1</captureSceneIDREF>
            <spatialInformation>
                <captureArea>
                        <bottomLeft>
                                <x>-3.0</x>
                        <y>20.0</y>
                        <z>9.0</z>
                        </bottomLeft>
                        <bottomRight>
                                <x>3.0</x>
                        <y>20.0</y>
                        <z>9.0</z>
                        </bottomRight>
                        <topLeft>
                                <x>-3.0</x>
                        <y>20.0</y>
                        <z>11.0</z>
                        </topLeft>
                        <topRight>
                                <x>3.0</x>
                        <y>20.0</y>
                        <z>11.0</z>
                        </topRight>
                </captureArea>
            </spatialInformation>
            <content>
                <sceneViewIDREF>SE1</sceneViewIDREF>
            </content>
            <policy>SoundLevel:0</policy>
            <encGroupIDREF>EG0</encGroupIDREF>
            <description lang="en">loudest room segment</description>
            <priority>2</priority>
            <lang>it</lang>
            <mobility>static</mobility>
            <view>individual</view>
        </mediaCapture>
        <mediaCapture
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:type="videoCaptureType" captureID="VC4"
              mediaType="video">
            <captureSceneIDREF>CS1</captureSceneIDREF>
            <spatialInformation>
                <captureOrigin>
                        <capturePoint>
                        <x>0.0</x>
                        <y>0.0</y>
                        <z>10.0</z>
                    </capturePoint>
                </captureOrigin>
                <captureArea>
                        <bottomLeft>
                                <x>-3.0</x>
                        <y>20.0</y>
                        <z>7.0</z>
                        </bottomLeft>
                        <bottomRight>
                                <x>3.0</x>
                        <y>20.0</y>
                        <z>7.0</z>
                        </bottomRight>
                        <topLeft>
                                <x>-3.0</x>
                        <y>20.0</y>
                        <z>13.0</z>
                        </topLeft>
                        <topRight>
                                <x>3.0</x>
                        <y>20.0</y>
                        <z>13.0</z>
                        </topRight>
                </captureArea>
            </spatialInformation>
            <individual>true</individual>
            <encGroupIDREF>EG0</encGroupIDREF>
            <description lang="en">
              zoomed out
              zoomed-out view of all people in the room
            </description>
            <priority>2</priority>
            <lang>it</lang>
            <mobility>static</mobility>
            <view>room</view>
            <capturedPeople>
                <personIDREF>alice</personIDREF>
                <personIDREF>bob</personIDREF>
                <personIDREF>ciccio</personIDREF>
            </capturedPeople>
        </mediaCapture>
        <mediaCapture
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:type="videoCaptureType" captureID="VC5"
              mediaType="video">
            <captureSceneIDREF>CS1</captureSceneIDREF>
            <spatialInformation>
                <captureArea>
                        <bottomLeft>
                                <x>-3.0</x>
                        <y>20.0</y>
                        <z>9.0</z>
                        </bottomLeft>
                        <bottomRight>
                                <x>3.0</x>
                        <y>20.0</y>
                        <z>9.0</z>
                        </bottomRight>
                        <topLeft>
                                <x>-3.0</x>
                        <y>20.0</y>
                        <z>11.0</z>
                        </topLeft>
                        <topRight>
                                <x>3.0</x>
                        <y>20.0</y>
                        <z>11.0</z>
                        </topRight>
                </captureArea>
            </spatialInformation>
            <content>
                <sceneViewIDREF>SE1</sceneViewIDREF>
            </content>
            <policy>SoundLevel:1</policy>
            <description lang="en">penultimate loudest room segment
            </description>
            <lang>it</lang>
            <mobility>static</mobility>
            <view>individual</view>
        </mediaCapture>
        <mediaCapture
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:type="videoCaptureType" captureID="VC6"
              mediaType="video">
            <captureSceneIDREF>CS1</captureSceneIDREF>
            <spatialInformation>
                <captureArea>
                        <bottomLeft>
                                <x>-3.0</x>
                        <y>20.0</y>
                        <z>9.0</z>
                        </bottomLeft>
                        <bottomRight>
                                <x>3.0</x>
                        <y>20.0</y>
                        <z>9.0</z>
                        </bottomRight>
                        <topLeft>
                                <x>-3.0</x>
                        <y>20.0</y>
                        <z>11.0</z>
                        </topLeft>
                        <topRight>
                                <x>3.0</x>
                        <y>20.0</y>
                        <z>11.0</z>
                        </topRight>
                </captureArea>
            </spatialInformation>
            <content>
                <sceneViewIDREF>SE1</sceneViewIDREF>
            </content>
            <policy>SoundLevel:2</policy>
            <description lang="en">last but two loudest room segment
            </description>
            <lang>it</lang>
            <mobility>static</mobility>
            <view>individual</view>
        </mediaCapture>
        <mediaCapture
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:type="videoCaptureType" captureID="VC7"
              mediaType="video">
            <captureSceneIDREF>CS1</captureSceneIDREF>
            <spatialInformation>
                <captureArea>
                        <bottomLeft>
                                <x>-3.0</x>
                        <y>20.0</y>
                        <z>9.0</z>
                        </bottomLeft>
                        <bottomRight>
                                <x>3.0</x>
                        <y>20.0</y>
                        <z>9.0</z>
                        </bottomRight>
                        <topLeft>
                                <x>-3.0</x>
                        <y>20.0</y>
                        <z>11.0</z>
                        </topLeft>
                        <topRight>
                                <x>3.0</x>
                        <y>20.0</y>
                        <z>11.0</z>
                        </topRight>
                </captureArea>
            </spatialInformation>
            <content>
                <mediaCaptureIDREF>VC3</mediaCaptureIDREF>
                <mediaCaptureIDREF>VC5</mediaCaptureIDREF>
                <mediaCaptureIDREF>VC6</mediaCaptureIDREF>
            </content>
            <maxCaptures exactNumber="true">3</maxCaptures>
            <encGroupIDREF>EG0</encGroupIDREF>
            <description lang="en">big picture of the current
            speaker + pips about previous speakers</description>
            <priority>3</priority>
            <lang>it</lang>
            <mobility>static</mobility>
            <view>individual</view>
        </mediaCapture>
    </mediaCaptures>
    <encodingGroups>
        <encodingGroup encodingGroupID="EG0">
            <maxGroupBandwidth>600000</maxGroupBandwidth>
            <encodingIDList>
                <encodingID>ENC1</encodingID>
                <encodingID>ENC2</encodingID>
                <encodingID>ENC3</encodingID>
            </encodingIDList>
        </encodingGroup>
        <encodingGroup encodingGroupID="EG1">
            <maxGroupBandwidth>300000</maxGroupBandwidth>
            <encodingIDList>
                <encodingID>ENC4</encodingID>
                <encodingID>ENC5</encodingID>
            </encodingIDList>
        </encodingGroup>
    </encodingGroups>
    <captureScenes>
        <captureScene scale="unknown" sceneID="CS1">
            <sceneViews>
                <sceneView sceneViewID="SE1">
                    <description lang="en">participants' individual
                    videos</description>
                    <mediaCaptureIDs>
                        <mediaCaptureIDREF>VC0</mediaCaptureIDREF>
                        <mediaCaptureIDREF>VC1</mediaCaptureIDREF>
                        <mediaCaptureIDREF>VC2</mediaCaptureIDREF>
                    </mediaCaptureIDs>
                </sceneView>
                <sceneView sceneViewID="SE2">
                    <description lang="en">loudest segment of the
                    room</description>
                    <mediaCaptureIDs>
                        <mediaCaptureIDREF>VC3</mediaCaptureIDREF>
                    </mediaCaptureIDs>
                </sceneView>
                <sceneView sceneViewID="SE5">
                    <description lang="en">loudest segment of the
                    room + pips</description>
                    <mediaCaptureIDs>
                        <mediaCaptureIDREF>VC7</mediaCaptureIDREF>
                    </mediaCaptureIDs>
                </sceneView>
                <sceneView sceneViewID="SE4">
                    <description lang="en">room audio</description>
                    <mediaCaptureIDs>
                        <mediaCaptureIDREF>AC0</mediaCaptureIDREF>
                    </mediaCaptureIDs>
                </sceneView>
                <sceneView sceneViewID="SE3">
                    <description lang="en">room video</description>
                    <mediaCaptureIDs>
                        <mediaCaptureIDREF>VC4</mediaCaptureIDREF>
                    </mediaCaptureIDs>
                </sceneView>
            </sceneViews>
        </captureScene>
    </captureScenes>
    <simultaneousSets>
        <simultaneousSet setID="SS1">
            <mediaCaptureIDREF>VC3</mediaCaptureIDREF>
            <mediaCaptureIDREF>VC7</mediaCaptureIDREF>
            <sceneViewIDREF>SE1</sceneViewIDREF>
        </simultaneousSet>
        <simultaneousSet setID="SS2">
            <mediaCaptureIDREF>VC0</mediaCaptureIDREF>
            <mediaCaptureIDREF>VC2</mediaCaptureIDREF>
            <mediaCaptureIDREF>VC4</mediaCaptureIDREF>
        </simultaneousSet>
    </simultaneousSets>
    <people>
        <person personID="bob">
            <personInfo>
                <ns2:fn>
                    <ns2:text>Bob</ns2:text>
                </ns2:fn>
            </personInfo>
            <personType>minute taker</personType>
        </person>
        <person personID="alice">
            <personInfo>
                <ns2:fn>
                    <ns2:text>Alice</ns2:text>
                </ns2:fn>
            </personInfo>
            <personType>presenter</personType>
        </person>
        <person personID="ciccio">
            <personInfo>
                <ns2:fn>
                    <ns2:text>Ciccio</ns2:text>
                </ns2:fn>
            </personInfo>
            <personType>chairman</personType>
            <personType>timekeeper</personType>
        </person>
    </people>
</clueInfo>

]]>
</artwork>
</figure>
]]></sourcecode>
    </section>

<section title="Diff with draft-ietf-clue-data-model-schema-16 version">
<t>
As per Alexey Melnikov's and Stefan Winter's comments: replaced wrong
references to RFC2119 in section 11.3 and section 11.5.
The updated reference

  </middle>
  <back>
    <references>
      <name>References</name>
      <references>
        <name>Normative References</name>

<!--draft-ietf-clue-framework-25 is 8845 -->
<reference anchor='RFC8845' target='https://www.rfc-editor.org/info/rfc8845'>
<front>
<title>Framework for Telepresence Multi-Streams</title>
<seriesInfo name='RFC' value='8845' />
<seriesInfo name='DOI' value='10.17487/RFC8845' />
<author initials='M' surname='Duckworth' fullname='Mark Duckworth' role='editor'>
    <organization />
</author>
<author initials='A' surname='Pepperell' fullname='Andrew Pepperell'>
    <organization />
</author>
<author initials='S' surname='Wenger' fullname='Stephan Wenger'>
    <organization />
</author>
<date month='June' year='2020' />
</front>
</reference>

<!--draft-ietf-clue-datachannel-18 is to RFC5646.
</t>
</section>

<section title="Diff with draft-ietf-clue-data-model-schema-15 version">
<t>
Applied modifications as per the following reviews: (i) Alexey
Melnikov's discuss and comments (abstract amendments, typo corrections,
insertion of references, etc.); (ii) Kathleen Moriarty's discuss and
comments (amendments to the Security Considerations section); (iii)
Stefan Winter's OPS-DIR review (use of enumerated types in the schema).
</t>
</section>

<section title="Diff with draft-ietf-clue-data-model-schema-14 version">
<t>
Applied modifications as per the following reviews: (i) Henry S.
Thompson's APPS-DIR review; (ii) Stefan Winter's OPS-DIR review; (iii)
Francis Dupont's GEN-ART review; (iv) Rich Salz's review (as part of
the security directorate's  ongoing effort to review all IETF documents
being processed by the IESG.)
</t>
</section>

<section title="Diff with draft-ietf-clue-data-model-schema-13 version">
<t>
Applied modifications as per the latest Area Director (Alissa Cooper's)
review comments.
</t>
</section>

<section title="Diff with draft-ietf-clue-data-model-schema-12 version">
<t>
Removed some typos and inconsistencies.
Applied modifications as per Alissa Cooper's review comments.
</t>
</section>

<section title="Diff with draft-ietf-clue-data-model-schema-11 version">
<t>
Applied modifications as per Mark Duckworth's review
(example corrections and maxCapturesType modification)</t>
<t>
maxCapturesType has been changed from positiveInteger to
unsignedShort excluding value 0.</t>
</section>

<section title="Diff with draft-ietf-clue-data-model-schema-10 version">
<t>
Minor modifications have been applied to address nits at page
https://www.ietf.org/tools/idnits?url=https://www.ietf.org/archive/id/
draft-ietf-clue-data-model-schema-10.txt.
</t>
</section>

<section title="Diff with draft-ietf-clue-data-model-schema-09 version">
<list style="symbols">
<t>We have introduced a &lt;captureOrigin&gt; element containing
a mandatory &lt;capturePoint&gt; and an optional
&lt;lineOfCapturePoint&gt; in the definition of
&lt;spatialInformation&gt; as per Paul's review
</t>
<t>A new type definition for switching policies (resembled by
&lt;policy&gt; element) has been provided in order to have acceptable
values in the form of "token:index".
</t>
<t>Minor modifications suggested in WGLC reviews have been applied.</t>
</list>
</section>

<section title="Diff with draft-ietf-clue-data-model-schema-08 version">
<list style="symbols">
<t>Typos correction</t>
</list>
</section>

<section title="Diff with draft-ietf-clue-data-model-schema-07 version">
<list style="symbols">
<t>IANA Considerations: text added</t>
<t>maxCaptureEncodings removed</t>
<t>personTypeType values aligned with CLUE framework</t>
<t>allowSubsetChoice added 8850 -->
<reference anchor='RFC8850' target='https://www.rfc-editor.org/info/rfc8850'>
<front>
<title>Controlling Multiple Streams for multiple content captures</t>
<t>embeddedText moved from videoCaptureType definition to
mediaCaptureType definition
</t>
<t>typos removed from section Terminology</t>
</list>
</section>
<section title="Diff with draft-ietf-clue-data-model-schema-06 version">
<list style="symbols">
<t>
Capture Scene Entry/Entries renamed as Capture Scene View/Views in the
text, &lt;sceneEntry&gt;/&lt;sceneEntries&gt; renamed as
&lt;sceneView&gt;/&lt;sceneViews&gt; in the XML schema.
</t>
<t>
Global Scene Entry/Entries renamed as Global View/Views in the text,
&lt;globalSceneEntry&gt;/&lt;globalSceneEntries&gt; renamed as
&lt;globalView&gt;/&lt;globalViews&gt;
</t>
<t>
Security section added.
</t>
<t>
Extensibility: a new type is introduced to describe other types of
 media capture (otherCaptureType), text
and example added.
</t>
<t>
Spatial information section updated: capture point optional, text now is
coherent with the framework one.
</t>
<t>
Audio capture description: &lt;sensitivityPattern&gt; added,
&lt;audioChannelFormat&gt; removed, &lt;captureArea&gt; disallowed.
</t>
<t>Simultaneous set definition: added &lt;captureSceneIDREF&gt; to refer
to capture scene identifiers as shortcuts and an optional mediaType
attribute which Telepresence (CLUE) Protocol Data Channel</title>
<seriesInfo name='RFC' value='8850' />
<seriesInfo name='DOI' value='10.17487/RFC8850' />
<author initials='C' surname='Holmberg' fullname='Christer Holmberg'>
    <organization />
</author>
<date month='June' year='2020' />
</front>
</reference>

<!--draft-ietf-clue-protocol-19 is mandatory to use when only capture scene identifiers
are listed.
</t>
<t>
Encoding groups: removed the constraint of the same media type.
</t>
<t>Updated text about media captures without &lt;encodingGroupIDREF&gt;
(optional in the XML schema).</t>
<t>
"mediaType" attribute removed from homogeneous groups of capture
(scene views and globlal views)
</t>
<t>
"mediaType" attribute removed from the global view textual description.
</t>
<t>"millimeters" scale value changed in "mm"</t>
</list>
</section>

<section title="Diff 8847 -->
<reference anchor='RFC8847' target='https://www.rfc-editor.org/info/rfc8847'>
<front>
<title>Protocol for Controlling Multiple Streams for Telepresence (CLUE)</title>
<seriesInfo name='RFC' value='8847' />
<seriesInfo name='DOI' value='10.17487/RFC8847' />
<author initials='R' surname='Presta' fullname='Roberta Presta'>
    <organization />
</author>
<author initials='S P' surname='Romano' fullname='Simon Pietro Romano'>
    <organization />
</author>
<date month='June' year='2020' />
</front>
</reference>

        <xi:include href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.2119.xml"/>

        <xi:include href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.6351.xml"/>

        <xi:include href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.5646.xml"/>

        <xi:include href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.7303.xml"/>

        <!--draft-ietf-ecrit-additional-data-38 is now RFC 7852-->
        <xi:include href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.7852.xml"/>

        <!--RFC 5226 was replaced with draft-ietf-clue-data-model-schema-04 version"> RFC 8126-->
        <xi:include href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.8126.xml"/>

        <xi:include href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.8174.xml"/>

      </references>
      <references>
        <name>Informative References</name>

        <xi:include href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.3688.xml"/>

        <xi:include href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.4353.xml"/>

        <xi:include href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.3550.xml"/>

        <xi:include href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.6838.xml"/>

        <xi:include href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.7667.xml"/>
      </references>
    </references>

 <section numbered="false" toc="default">
      <name>Acknowledgements</name>
      <t>
 <list syle="symbols">
  <t>globalCaptureEntries/Entry renamed as globalSceneEntries/Entry;</t>
  <t>sceneInformation added;</t>
 <t>Only capture scene entry identifiers listed within global scene
 entries (media capture identifiers removed);</t>
 <t>&lt;participants&gt; renamed as &lt;people&gt; in the
 &gt;clueInfo&lt; template</t>
 <t>&lt;vcard&gt; renamed as &lt;personInfo&gt; to synch
 with the framework terminology</t>
 <t>&lt;participantType&gt; renamed as &lt;personType&gt;
 to synch
<!--[rfced] We replaced "precious" with the framework terminology</t>
 <t>&lt;participantIDs&gt; renamed as &lt;capturedPeople&gt; "valuable" in the
 media capture type definition to remove ambiguity</t>
 <t>Examples have been updated with the new definitions of
 &lt;globalSceneEntries&gt; and of &lt;people&gt;.</t>
 </list>
 </t>
</section>

<section title="Diff with draft-ietf-clue-data-model-schema-03 version">
 <t>
 <list syle="symbols">
 <t>encodings section has been removed</t>
 <t>global capture entries have been introduced</t>
 <t>capture scene entry identifiers are used following
sentence as shortcuts in
 listing we thought it was a better word choice per the content of
 MCC (similarly to simultaneous set and global capture entries)</t>
 <t>Examples have been updated. A new example with global capture
 entries has been added.</t>
 <t>&lt;encGroupIDREF&gt; has been made optional.</t>
 <t>&lt;single&gt; has been renamed into &lt;individual&gt;</t>
 <t>Obsolete comments have been removed.</t>
 <t>participants information has been added.</t>
 </list>
 </t>
</section>

<section title="Diff with draft-ietf-clue-data-model-schema-02 version">
 <t>
 <list syle="symbols">
 <t>captureParameters and encodingParameters have been removed from
context.  Please let us know if you prefer otherwise.

Original:
   The authors thank all the
 captureEncodingType</t>
 <t>data model example has been updated CLUErs for their precious feedbacks and validated
 according to the new schema. Further description of support.

Current:
   The authors thank all the
 represented scenario has been provided.</t>
 <t>A multiple content capture example has been added.</t>
 <t>Obsolete comments CLUErs for their valuable feedback and  references have been removed.</t>
 </list>
 </t>
 </section>

<section title="Acknowledgments">
<t> support.
-->

The authors thank all the CLUErs for their precious feedbacks valuable feedback and
support. Thanks also to Alissa Cooper, <contact fullname="Alissa Cooper"/>, whose AD reviews review
helped us improve the quality of the document.
</t>
    </section>

</middle>

<back>

  <references title="Normative References">

    <!-- clue framework -->
    <?rfc include="reference.I-D.ietf-clue-framework"?>

<!-- clue [rfced] Throughout the text, the following terminology appears to
be used inconsistently. Please review these occurrences and let
us know if/how they may be made consistent (and if 'XML Schema'
is the same as 'XML Schema data channel -->
    <?rfc include="reference.I-D.ietf-clue-datachannel"?>

	<!-- RFC7303 -->
  	<?rfc include="reference.RFC.7303"?>

	<!-- clue protocol -->
    <?rfc include="reference.I-D.ietf-clue-protocol"?>

	<!-- ecrit -->
	<?rfc include="reference.I-D.ietf-ecrit-additional-data"?>

		<!-- RFC2119 -->
	<?rfc include="reference.RFC.2119"?>

	<!-- RFC6351 -->
	<?rfc include="reference.RFC.6351"?>

	<!-- RFC5646 -->
	<?rfc include="reference.RFC.5646"?>

	<!-- RFC5646 -->
	<?rfc include="reference.RFC.5226"?>
  </references>

  <references title="Informative References">

 	<!-- RFC3688 -->
	<?rfc include="reference.RFC.3688"?>

 	<!-- RFC4353 -->
	<?rfc include="reference.RFC.4353"?>

	<!-- RFC3550 -->
	<?rfc include="reference.RFC.3550"?>

		<!-- RFC6838 -->
	<?rfc include="reference.RFC.6838"?>

	<!-- RFC7667 model').

   XML Schema vs. XML schema

   XML Schema data model
   CLUE data model schema
   telepresence data model
-->
  	<?rfc include="reference.RFC.7667"?>

  </references>

  </back>
</rfc>