<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<xs:schema version="1.0"
	targetNamespace="http://weblab-project.org/core/model/"
	xmlns:tns="http://weblab-project.org/core/model/"
	xmlns:xs="http://www.w3.org/2001/XMLSchema">

	<xs:annotation>
		<xs:documentation>
			Data Exchange Model for WebLab platform provided by EADS
			Core package - Version 1.0 - 2008/05
		</xs:documentation>
	</xs:annotation>

	<xs:complexType name="resource">
		<xs:annotation>
			<xs:documentation>
				A resource refers to any object that could be
				manipulated in the WebLab platform. It will be
				identified by a unique URI. It can hold some annotations
				that will describe the resource itself at a semantic
				level. It can also hold some low level descriptors that
				are describing itself at a lower level. It will be a
				common interface which will be inherited by almost all
				WebLab objects.

				Any reference to a resource will use its URI.

				Data Exchange Model for WebLab platform provided by EADS
				Core package - Version 1.0 - 2008/05
			</xs:documentation>
		</xs:annotation>
		<xs:sequence>
			<xs:element name="annotation" type="tns:annotation"
				minOccurs="0" maxOccurs="unbounded">
				<xs:annotation>
					<xs:documentation>
						A list of annotations describing the resource.
					</xs:documentation>
				</xs:annotation>
			</xs:element>
			<xs:element name="descriptor" type="tns:lowLevelDescriptor"
				minOccurs="0" maxOccurs="unbounded">
				<xs:annotation>
					<xs:documentation>
						A list of low level descriptors describing the
						resource.
					</xs:documentation>
				</xs:annotation>
			</xs:element>
		</xs:sequence>
		<xs:attribute name="uri" type="xs:anyURI">
			<xs:annotation>
				<xs:documentation>
					The unique identifier of the resource.
				</xs:documentation>
			</xs:annotation>
		</xs:attribute>
	</xs:complexType>


	<xs:complexType name="annotation">
		<xs:annotation>
			<xs:documentation>
				Annotation object should be understood as the definition
				provided by the W3C in its resource description
				framework. It will contain a set of annotations which
				refer to a specific resource known as the subject of the
				annotations. Thus an annotation object is fully
				dependant on the resource it describes. One can note
				that we involve the RDF methodology concepts and design
				formalism which should not be misunderstood as the
				RDF/XML serialisation format.

				Annotation is one of the major objects manipulated
				through the WebLab platform since it will allow adding
				any particular information on any type of WebLab
				resource. For example, many process services will add
				annotations in order to link the extracted information
				to the resource processed (i.e. a language recognition
				service will annotate a document in order to note the
				language identified, or perhaps that the language could
				not be recognised).

				Each annotation is composed of a set of statements
				composed of a set of triple: subject, property and
				object. Thus any description can be applied on any
				resource as soon as the property and object element
				refer to a consistent vocabulary in a certain domain.
				This vocabulary could be expressed in accordance to a
				specified ontology. However, one of the project's
				guidelines is extensibility, thus annotation should be
				adapted. The set of triple statements described a
				resource will be contained in the annotation object
				serialised in the RDF/XML format.

				Since an annotation is a resource, it can also contain
				annotations. The contained statements can be seen as
				meta-annotations describing, for example, how and when
				the first level of annotations has been created (which
				service with what resource or configuration).

				Data Exchange Model for WebLab platform provided by EADS
				Core package - Version 1.0 - 2008/05
			</xs:documentation>
		</xs:annotation>
		<xs:complexContent>
			<xs:extension base="tns:resource">
				<xs:sequence>
					<xs:element name="data" type="xs:anyType"
						minOccurs="1" maxOccurs="1">
						<xs:annotation>
							<xs:documentation>
								Should be RDF/XML content.
							</xs:documentation>
						</xs:annotation>
					</xs:element>
				</xs:sequence>
			</xs:extension>
		</xs:complexContent>
	</xs:complexType>


	<xs:complexType name="mediaUnit" abstract="true">
		<xs:annotation>
			<xs:documentation>
				This is the major object manipulated through the WebLab
				platform. It is mainly assumed that almost all
				processing services should accept the media unit as a
				common argument and provide enhanced media unit as a
				result.

				A media unit can be defined as the structural annotable
				representation of any multimedia content. It is a
				resource and thus can be retrieved by an URI and
				annotated by any kind of descriptive annotations or low
				level descriptors. As described in the following
				sections any particular type of media (i.e. picture,
				text, video segment, audio sample or video frame...)
				will inherit from this object.

				It could have a composed unit as a parent when it is
				contained in a group of units. Finally it could contain
				annotable segments which will allow describing sub-parts
				of its own content.

				Data Exchange Model for WebLab platform provided by EADS
				Core package - Version 1.0 - 2008/05
			</xs:documentation>
		</xs:annotation>
		<xs:complexContent>
			<xs:extension base="tns:resource">
				<xs:sequence>
					<xs:element name="segment" type="tns:segment"
						minOccurs="0" maxOccurs="unbounded">
						<xs:annotation>
							<xs:documentation>
								A list of segments.
							</xs:documentation>
						</xs:annotation>
					</xs:element>
				</xs:sequence>
			</xs:extension>
		</xs:complexContent>
	</xs:complexType>


	<xs:complexType name="composedUnit">
		<xs:annotation>
			<xs:documentation>
				A composed unit is a media unit which only contain a
				list of other units. Thus it can be viewed as a common
				container handling the global structure description of a
				multimedia document. The intern media unit can be
				organised sequentially (i.e. multiple text section) or
				in parallel and synchronised (i.e. audio speech of a
				video, speech transcription or multiple translation of
				the same text content). In order to reflect this
				capability a specific boolean attribute will mark if the
				unit are synchronised (i.e. "true" means synchronised
				units and "false" sequential units).

				As a resource, a composed unit could be annotated to
				provide, for example, meta-information on its content or
				on the relation which links the different unit composing
				its content.

				Data Exchange Model for WebLab platform provided by EADS
				Core package - Version 1.0 - 2008/05
			</xs:documentation>
		</xs:annotation>
		<xs:complexContent>
			<xs:extension base="tns:mediaUnit">
				<xs:sequence>
					<xs:element name="mediaUnit" type="tns:mediaUnit"
						minOccurs="0" maxOccurs="unbounded">
						<xs:annotation>
							<xs:documentation>
								A list of media units.
							</xs:documentation>
						</xs:annotation>
					</xs:element>
				</xs:sequence>
				<xs:attribute name="synchronised" type="xs:boolean"
					use="required">
					<xs:annotation>
						<xs:documentation>
							Whether or not media units are synchronised.
						</xs:documentation>
					</xs:annotation>
				</xs:attribute>
			</xs:extension>
		</xs:complexContent>
	</xs:complexType>


	<xs:complexType name="document">
		<xs:annotation>
			<xs:documentation>
				A document is assumed to be a composed unit which handle
				the references of all the unit which have been build on
				it through the multiple processes.

				As a resource, a document could be annotated to provide,
				for example, meta-information on the original document
				source, the author or the original creation date...

				Data Exchange Model for WebLab platform provided by EADS
				Core package - Version 1.0 - 2008/05
			</xs:documentation>
		</xs:annotation>
		<xs:complexContent>
			<xs:extension base="tns:composedUnit" />
		</xs:complexContent>
	</xs:complexType>


	<xs:complexType name="segment" abstract="true">
		<xs:annotation>
			<xs:documentation>
				A segment is a resource that should not have any content
				and which is linked to a media unit. It allows
				describing the content of a unit with at much finer
				level. The segment could be annotated as it inherits
				from resource. It provides a way to assign annotation on
				a very high level of structure description without
				adding weight to the model by transporting the data.

				The object will contain positioning information which
				allows localising itself in the parent unit. As media
				type are very different the position itself will be
				specialised to them and thus provide localisation
				adapted to the media.

				This object cannot be used itself (this is an abstract
				object). However, some implementations with real
				capabilities must be developed in order to match every
				media class. A class of media stands here for a list of
				segments which can be localised in the same manner. For
				example, a text section can be described in the same way
				as a video segment: both of them need a start and stop
				index, one referring to character index and the other to
				a temporal reference.

				Data Exchange Model for WebLab platform provided by EADS
				Core package - Version 1.0 - 2008/05
			</xs:documentation>
		</xs:annotation>
		<xs:complexContent>
			<xs:extension base="tns:resource" />
		</xs:complexContent>
	</xs:complexType>


	<xs:complexType name="resourceCollection">
		<xs:annotation>
			<xs:documentation>
				A resource collection defines a simple list of resources
				and allows to regroup them with a common meaning or
				utility. Since a multimedia document is a resource, the
				simplest resource collection will be a corpus of
				documents such as the video about the same program
				during one year. It could also be a set of useful
				resource needed by a service such as a set of
				annotations.

				As a common design principle, a resource collection
				should not refer to a heterogeneous set of resources
				(i.e. a document and a query). However, such specific
				case could be tackled by a collection of collection
				which will themselves be consistent (same resource
				type).

				As a resource, a resource collection could be annotated
				to provide, for example, meta-information on its content
				or the reasons of the collection.

				Data Exchange Model for WebLab platform provided by EADS
				Core package - Version 1.0 - 2008/05
			</xs:documentation>
		</xs:annotation>
		<xs:complexContent>
			<xs:extension base="tns:resource">
				<xs:sequence>
					<xs:element name="resource" type="tns:resource"
						minOccurs="1" maxOccurs="unbounded">
						<xs:annotation>
							<xs:documentation>
								A list of resources.
							</xs:documentation>
						</xs:annotation>
					</xs:element>
				</xs:sequence>
			</xs:extension>
		</xs:complexContent>
	</xs:complexType>


	<xs:complexType name="lowLevelDescriptor">
		<xs:annotation>
			<xs:documentation>
				A low level descriptor is composed of a set features
				that have been extracted from a document or a part of
				document.

				It aims at representing low level annotation (not at a
				semantic level but at a numerical level) mainly for
				computing similarity between objects For instance, Text
				could use lowLevelDescriuptor to store TFIDF values,
				Image could use lowLevelDescriuptor to handle color
				histograms.

				A low level descriptor may be composed of a set of
				features for instance, an image may contains edge
				feature Vector as well as red color histogram vector

				As a resource, a low level descriptor could be annotated
				to provide, for example, meta information on its
				creation date, its version or its application domain.

				Data Exchange Model for WebLab platform provided by EADS
				Core package - Version 1.0 - 2008/05
			</xs:documentation>
		</xs:annotation>
		<xs:complexContent>
			<xs:extension base="tns:resource">
				<xs:sequence>
					<xs:element name="feature" type="tns:feature"
						minOccurs="1" maxOccurs="unbounded">
						<xs:annotation>
							<xs:documentation>
								A list of features.
							</xs:documentation>
						</xs:annotation>
					</xs:element>
				</xs:sequence>
				<xs:attribute name="key" type="xs:string"
					use="required">
					<xs:annotation>
						<xs:documentation>
							A key for the low level descriptor. Ex.
							"ImageFeatures"
						</xs:documentation>
					</xs:annotation>
				</xs:attribute>
			</xs:extension>
		</xs:complexContent>
	</xs:complexType>


	<xs:complexType name="feature">
		<xs:annotation>
			<xs:documentation>
				A low level feature vector, for instance a TFIDF vector,
				a Red histogram vector etc.

				Data Exchange Model for WebLab platform provided by EADS
				Core package - Version 1.0 - 2008/05
			</xs:documentation>
		</xs:annotation>
		<xs:sequence>
			<xs:element name="value" minOccurs="1" maxOccurs="1">
				<xs:simpleType>
					<xs:list itemType="xs:anySimpleType">
						<xs:annotation>
							<xs:documentation>
								A list of value that are simple types.
								(i.e. numbers, boolean or string for
								instance).
							</xs:documentation>
						</xs:annotation>
					</xs:list>
				</xs:simpleType>
			</xs:element>
		</xs:sequence>
		<xs:attribute name="label" use="optional">
			<xs:annotation>
				<xs:documentation>
					A non-compulsory identifier for this feature.
				</xs:documentation>
			</xs:annotation>
		</xs:attribute>
	</xs:complexType>

</xs:schema>