XML Schema Documentation

Schema Document Properties

Properties

Target Namespace	https://schema.omnius.com/pagesformat/2022.03.01
Element and Attribute Namespaces	Global element and attribute declarations belong to this schema's target namespace. By default, local element declarations belong to this schema's target namespace. By default, local attribute declarations have no namespace.

This Schema defines the omni:us Pages Format (OPF), intended for storing data associated to one or more images of digitized documents. This format is designed to be very general so that it can be used for several purposes, such as storing ground truth data or results of automatic recognition processes. It is also intended to store many possible levels of data, such as layout and transcripts at region, line, word and glyph levels. General structure ================= An OPF XML is composed of one or more Page elements, each corresponding to a page of a document. The Page elements have an imageFilename attribute which links to a file from where to get the corresponding page image. This could be a path (absolute or relative to the location of the XML) in the local machine or a URL to retrieve it remotely. The file should normally be an image or a PDF file. In case of multipage images or PDFs, the imageFilename should end with the page number within square brackets being the page number 0 based (ImageMagick notation). The Page elements also have attributes for the width and height of the page, which defines the scale for all coordinates within this page. Within each page there can be words, text lines and different kinds of regions (text, table, image, separator and custom). Within table regions there can be words, text lines, text regions and separator regions. Within text regions there can be words and text lines. Within text lines there can only be words. And finally within words there can only be glyphs. All of these elements can optionally have a Coords element which defines its geometry. In the case of text lines, there is an additional geometry element which is its baseline. The elements that relate to text, i.e., text regions, text lines, words and glyphs, can have TextEquiv elements that contains its corresponding text content. A single element may have more than one TextEquiv element to store for instance multiple recognition hypotheses, though all of them must have a unique type attribute. Most elements can have one or more property elements, though their keys are required to be unique. These are intended to store generic information, for example whether an element is of a given class. As children of the root PcGts node apart from Page elements there can also be Groups. A Group encodes a relationship between multiple elements. For example, there could be text regions for paragraphs and a group to indicate all paragraphs that belong to a single column. Another example could be that in a document there is some text representing a key and some other text its value, a relationship which could be encoded with a Group. All elements that are a result of an automatic recognition can and should have a conf attribute indicating the confidence of this recognition. Reading order ------------- The reading order of words within lines, lines within regions, pages within the document, etc. is implied by the order of the elements in the XML. If lines in a region do not have an explicit reading order, then they shouldn't be part of the same region, for example a paragraph and a side note. Text lines ---------- For the purpose of this format, a text line is defined as a series of words that are next to each other without overlapping along the reading direction. For latin languages this would be words from left to right that are all at the same vertical position and that the next word always starts more to the right than the end of the previous word. This means that if in some text a word was missing and later written between two lines, since there was no space for it, then this inserted word is considered as a different line. If there is an insertion symbol, then this symbol should be added to the corresponding line transcript where it visibly appears. Baselines --------- The order of the points in the baselines should always be left-to-right for both text which is read left-to-right and right-to-left. Coordinates ----------- The Coords of elements defining its geometry in general can be any polygon without restrictions. However, similar to the baselines, the order of the points normally is used to encode directionality. The first point should be the top-left corner and the rest be in clockwise order. The top-left is with respect to the actual orientation of the respective content, not the orientation of the page. For example, a text line which is vertical in the page, reading from bottom to top, its top-left would be the point closest to the bottom-left of the page. Additional non-schema requirements and recommendations ====================================================== To prevent development errors and ease debugging of problems, a few requirements and recommendations described next should be followed. - All processing tools should at least validate input/output XMLs against this schema. - All XMLs should be in utf-8 encoding. - The default namespace of the XMLs should be the OPF namespace. - Attributes of the XML should be sorted alphabetically. This is so that when comparing versions of the XML, differences can be observed at a word/token level and ease viewing only the things that did change. - When pretty printing the XML, it should be indented using 2 spaces and elements without content should always be self-closed. Relation to PRImA PAGE XML ========================== The format is highly based on the [PRImA PAGE XML format](https://github.com/PRImA-Research-Lab/PAGE-XML) for page content. The names of the XML elements are mostly the same. The most notable differences are the following: - It allows to include information about a whole document, not just a single page, i.e., the XMLs can contain multiple Page elements. - Only a subset of features from PRImA PAGE XML is allowed. - Since many region types have been removed, as alternative there is a new CustomRegion with a type attribute. - Coordinates are allowed to be floating point numbers, not just integers. - It defines Property elements which can be used for diverse generic purposes. - TextLines are allowed as children of Page and TableRegion elements, words are allowed as children of Page, TextRegion and TableRegion elements, and TextRegions can also be children of TableRegions. - There is a generic Group element stored as children of the PcGts root node which references one or more IDs that can reference any element type. - Page elements optionally can have an ID attribute. - Most elements allow a setBy attribute to identify who/what created it. - Process elements can be added to the Metadata to document details of processes run on the document.

Declared Namespaces

Prefix	Namespace
Default namespace	https://schema.omnius.com/pagesformat/2022.03.01
xml	http://www.w3.org/XML/1998/namespace
xs	http://www.w3.org/2001/XMLSchema

Schema Component Representation

<xs:schema targetNamespace="https://schema.omnius.com/pagesformat/2022.03.01" elementFormDefault="qualified">
...
</xs:schema>

Global Declarations

Element: PcGts

Properties

Name	PcGts
Type	Locally-defined complex type
Nillable	no
Abstract	no

Documentation

XML Instance Representation

<PcGts
 id="xs:ID" [0..1]
>
   <Metadata> MetadataType </Metadata> [1]
   <Property> PropertyType </Property> [0..*]
   <Page> PageType </Page> [1..*]
   <Group> GroupType </Group> [0..*]
</PcGts>

Schema Component Representation

<xs:element name="PcGts">
   <xs:complexType>
      <xs:sequence>
         <xs:element name="Metadata" type="MetadataType"/>
         <xs:element name="Property" type="PropertyType" minOccurs="0" maxOccurs="unbounded"/>
         <xs:element name="Page" type="PageType" minOccurs="1" maxOccurs="unbounded"/>
         <xs:element name="Group" type="GroupType" minOccurs="0" maxOccurs="unbounded"/>
      </xs:sequence>
      <xs:attribute name="id" type="xs:ID" use="optional"/>
   </xs:complexType>
</xs:element>

Global Definitions

Complex Type: BaselineType

Type hierarchy

Super-types:	None
Sub-types:	None

Properties

Name	BaselineType
Abstract	no

Documentation

XML Instance Representation

<...
 points="PointsType" [1]
 conf="ConfType" [0..1]
 setBy="NotEmptyType" [0..1]
/>

Schema Component Representation

<xs:complexType name="BaselineType">
   <xs:attribute name="points" type="PointsType" use="required"/>
   <xs:attribute name="conf" type="ConfType" use="optional"/>
   <xs:attribute name="setBy" type="NotEmptyType" use="optional"/>
</xs:complexType>

Complex Type: CoordsType

Type hierarchy

Super-types:	None
Sub-types:	None

Properties

Name	CoordsType
Abstract	no

Documentation

XML Instance Representation

<...
 points="PointsType" [1]
 conf="ConfType" [0..1]
 setBy="NotEmptyType" [0..1]
/>

Schema Component Representation

<xs:complexType name="CoordsType">
   <xs:attribute name="points" type="PointsType" use="required"/>
   <xs:attribute name="conf" type="ConfType" use="optional"/>
   <xs:attribute name="setBy" type="NotEmptyType" use="optional"/>
</xs:complexType>

Complex Type: CustomRegionType

Type hierarchy

Super-types:	RegionType < CustomRegionType (by extension)
Sub-types:	None

Properties

Name	CustomRegionType
Abstract	no

Documentation

XML Instance Representation

<...
 id="xs:ID" [1]
 orientation="AngleType" [0..1]Attribute orientation

          Angle that the region has to be rotated in clockwise direction
          in order to correct the skew (negative values indicate
          anti-clockwise rotation). Range: (-180,180].
        
 
 
 type="NotEmptyType" [0..1]Attribute type

              Information on the type of content represented by this region.
            
 
 
>
   <Property> PropertyType </Property> [0..*]
   <Coords> CoordsType </Coords> [0..1]
</...>

Schema Component Representation

<xs:complexType name="CustomRegionType">
   <xs:complexContent>
      <xs:extension base="RegionType">
         <xs:attribute name="type" type="NotEmptyType" use="optional"/>
      </xs:extension>
   </xs:complexContent>
</xs:complexType>

Complex Type: GlyphType

Type hierarchy

Super-types:	None
Sub-types:	None

Properties

Name	GlyphType
Abstract	no

Documentation

XML Instance Representation

<...
 id="xs:ID" [1]
>
   <Property> PropertyType </Property> [0..*]
   <Coords> CoordsType </Coords> [0..1]
   <TextEquiv> TextEquivType </TextEquiv> [0..*]
</...>

Schema Component Representation

<xs:complexType name="GlyphType">
   <xs:sequence>
      <xs:element name="Property" type="PropertyType" minOccurs="0" maxOccurs="unbounded"/>
      <xs:element name="Coords" type="CoordsType" minOccurs="0" maxOccurs="1"/>
      <xs:element name="TextEquiv" type="TextEquivType" minOccurs="0" maxOccurs="unbounded"/>
   </xs:sequence>
   <xs:attribute name="id" type="xs:ID" use="required"/>
</xs:complexType>

Complex Type: GroupType

Type hierarchy

Super-types:	None
Sub-types:	None

Properties

Name	GroupType
Abstract	no

Documentation

XML Instance Representation

<...
 conf="ConfType" [0..1]
 setBy="NotEmptyType" [0..1]
 id="xs:ID" [1]
>
   <Property> PropertyType </Property> [0..*]
   <Member> MemberType </Member> [1..*]
</...>

Schema Component Representation

<xs:complexType name="GroupType">
   <xs:sequence>
      <xs:element name="Property" type="PropertyType" minOccurs="0" maxOccurs="unbounded"/>
      <xs:element name="Member" type="MemberType" minOccurs="1" maxOccurs="unbounded"/>
   </xs:sequence>
   <xs:attribute name="conf" type="ConfType" use="optional"/>
   <xs:attribute name="setBy" type="NotEmptyType" use="optional"/>
   <xs:attribute name="id" type="xs:ID" use="required"/>
</xs:complexType>

Complex Type: ImageOrientationType

Type hierarchy

Super-types:	None
Sub-types:	None

Properties

Name	ImageOrientationType
Abstract	no

Documentation

XML Instance Representation

<...
 angle="xs:string (pattern = (-90|0|90|180))" [1]
 conf="ConfType" [0..1]
 setBy="NotEmptyType" [0..1]
/>

Schema Component Representation

<xs:complexType name="ImageOrientationType">
   <xs:attribute name="angle" use="required">
      <xs:simpleType>
         <xs:restriction base="xs:string">
            <xs:pattern value="(-90|0|90|180)"/>
         </xs:restriction>
      </xs:simpleType>
   </xs:attribute>
   <xs:attribute name="conf" type="ConfType" use="optional"/>
   <xs:attribute name="setBy" type="NotEmptyType" use="optional"/>
</xs:complexType>

Complex Type: ImageRegionType

Type hierarchy

Super-types:	RegionType < ImageRegionType (by extension)
Sub-types:	None

Properties

Name	ImageRegionType
Abstract	no

Documentation

XML Instance Representation

<...
 id="xs:ID" [1]
 orientation="AngleType" [0..1]Attribute orientation

          Angle that the region has to be rotated in clockwise direction
          in order to correct the skew (negative values indicate
          anti-clockwise rotation). Range: (-180,180].
        
 
 
>
   <Property> PropertyType </Property> [0..*]
   <Coords> CoordsType </Coords> [0..1]
</...>

Schema Component Representation

<xs:complexType name="ImageRegionType">
   <xs:complexContent>
      <xs:extension base="RegionType"/>
   </xs:complexContent>
</xs:complexType>

Complex Type: MemberType

Type hierarchy

Super-types:	None
Sub-types:	None

Properties

Name	MemberType
Abstract	no

Documentation

XML Instance Representation

<...
 conf="ConfType" [0..1]
 ref="xs:IDREF" [1]Attribute ref

          ID of the element that is member.
        
 
 
/>

Schema Component Representation

<xs:complexType name="MemberType">
   <xs:attribute name="conf" type="ConfType" use="optional"/>
   <xs:attribute name="ref" type="xs:IDREF" use="required"/>
</xs:complexType>

Complex Type: MetadataType

Type hierarchy

Super-types:	None
Sub-types:	None

Properties

Name	MetadataType
Abstract	no

Documentation

XML Instance Representation

<...>
   <Creator> NotEmptyType </Creator> [1]
   <Created> xs:dateTime </Created> [1]
   <LastChange> xs:dateTime </LastChange> [1]
   <Process> ProcessType </Process> [0..*]
</...>

Schema Component Representation

<xs:complexType name="MetadataType">
   <xs:sequence>
      <xs:element name="Creator" type="NotEmptyType"/>
      <xs:element name="Created" type="xs:dateTime"/>
      <xs:element name="LastChange" type="xs:dateTime"/>
      <xs:element name="Process" type="ProcessType" minOccurs="0" maxOccurs="unbounded"/>
   </xs:sequence>
</xs:complexType>

Complex Type: PageType

Type hierarchy

Super-types:	None
Sub-types:	None

Properties

Name	PageType
Abstract	no

Documentation

XML Instance Representation

<...
 id="xs:ID" [0..1]
 imageFilename="NotEmptyType" [1]Attribute imageFilename

          A path in the local machine absolute or relative to the location
          of the XML, or a URL from where to get the file. If the file corresponds
          to a multipage image or PDF, then the path/URL must be followed by the
          page number (0 based) within square brackets. For example `file.pdf[0]`.
        
 
 
 imageWidth="xs:int" [1]
 imageHeight="xs:int" [1]
>
   <ImageOrientation> ImageOrientationType </ImageOrientation> [0..1]
   <Property> PropertyType </Property> [0..*]
   Start Choice [0..*]
      <Word> WordType </Word> [1]
      <TextLine> TextLineType </TextLine> [1]
      <TextRegion> TextRegionType </TextRegion> [1]
      <TableRegion> TableRegionType </TableRegion> [1]
      <ImageRegion> ImageRegionType </ImageRegion> [1]
      <SeparatorRegion> SeparatorRegionType </SeparatorRegion> [1]
      <CustomRegion> CustomRegionType </CustomRegion> [1]
   End Choice
</...>

Schema Component Representation

<xs:complexType name="PageType">
   <xs:sequence>
      <xs:element name="ImageOrientation" type="ImageOrientationType" minOccurs="0" maxOccurs="1"/>
      <xs:element name="Property" type="PropertyType" minOccurs="0" maxOccurs="unbounded"/>
      <xs:choice minOccurs="0" maxOccurs="unbounded">
         <xs:element name="Word" type="WordType"/>
         <xs:element name="TextLine" type="TextLineType"/>
         <xs:element name="TextRegion" type="TextRegionType"/>
         <xs:element name="TableRegion" type="TableRegionType"/>
         <xs:element name="ImageRegion" type="ImageRegionType"/>
         <xs:element name="SeparatorRegion" type="SeparatorRegionType"/>
         <xs:element name="CustomRegion" type="CustomRegionType"/>
      </xs:choice>
   </xs:sequence>
   <xs:attribute name="id" type="xs:ID" use="optional"/>
   <xs:attribute name="imageFilename" type="NotEmptyType" use="required"/>
   <xs:attribute name="imageWidth" type="xs:int" use="required"/>
   <xs:attribute name="imageHeight" type="xs:int" use="required"/>
</xs:complexType>

Complex Type: ProcessType

Type hierarchy

Super-types:	None
Sub-types:	None

Properties

Name	ProcessType
Abstract	no

Documentation

XML Instance Representation

<...
 id="xs:ID" [0..1]Attribute id

          Short identifier of the process. For simplicity in general it could
          be ps1, ps2, etc.
        
 
 
 started="xs:dateTime" [1]Attribute started

          Date and time in UTC of when the process started using the XSD
          dateTime format, i.e., YYYY-MM-DDThh:mm:ssZ.
        
 
 
 time="xs:float" [1]Attribute time

          Total time the process took in seconds.
        
 
 
 tool="NotEmptyType" [1]Attribute tool

          Name of the tool used to process, its version, platform it was run
          on, configuration values, etc.
        
 
 
 ref="NotEmptyType" [0..1]Attribute ref

          Reference to the tool execution instance. It should allow locating the
          output logs. For human edits, it should allow to determine the person.
        
 
 
/>

Schema Component Representation

<xs:complexType name="ProcessType">
   <xs:attribute name="id" type="xs:ID" use="optional"/>
   <xs:attribute name="started" type="xs:dateTime" use="required"/>
   <xs:attribute name="time" type="xs:float" use="required"/>
   <xs:attribute name="tool" type="NotEmptyType" use="required"/>
   <xs:attribute name="ref" type="NotEmptyType" use="optional"/>
</xs:complexType>

Complex Type: PropertyType

Type hierarchy

Super-types:	None
Sub-types:	None

Properties

Name	PropertyType
Abstract	no

Documentation

XML Instance Representation

<...
 key="xs:string (pattern = [a-zA-Z0-9_.-]+)" [1]
 value="NotEmptyType" [0..1]
 conf="ConfType" [0..1]
 setBy="NotEmptyType" [0..1]
/>

Schema Component Representation

<xs:complexType name="PropertyType">
   <xs:attribute name="key" use="required">
      <xs:simpleType>
         <xs:restriction base="xs:string">
            <xs:pattern value="[a-zA-Z0-9_.-]+"/>
         </xs:restriction>
      </xs:simpleType>
   </xs:attribute>
   <xs:attribute name="value" type="NotEmptyType" use="optional"/>
   <xs:attribute name="conf" type="ConfType" use="optional"/>
   <xs:attribute name="setBy" type="NotEmptyType" use="optional"/>
</xs:complexType>

Complex Type: RegionType

Type hierarchy

Super-types:	None
Sub-types:	TextRegionType (by extension) ImageRegionType (by extension) TableRegionType (by extension) SeparatorRegionType (by extension) CustomRegionType (by extension)

Properties

Name	RegionType
Abstract	yes

Documentation

XML Instance Representation

<...
 id="xs:ID" [1]
 orientation="AngleType" [0..1]Attribute orientation

          Angle that the region has to be rotated in clockwise direction
          in order to correct the skew (negative values indicate
          anti-clockwise rotation). Range: (-180,180].
        
 
 
>
   <Property> PropertyType </Property> [0..*]
   <Coords> CoordsType </Coords> [0..1]
</...>

Schema Component Representation

<xs:complexType name="RegionType" abstract="true">
   <xs:sequence>
      <xs:element name="Property" type="PropertyType" minOccurs="0" maxOccurs="unbounded"/>
      <xs:element name="Coords" type="CoordsType" minOccurs="0" maxOccurs="1"/>
   </xs:sequence>
   <xs:attribute name="id" type="xs:ID" use="required"/>
   <xs:attribute name="orientation" type="AngleType" use="optional"/>
</xs:complexType>

Complex Type: SeparatorRegionType

Type hierarchy

Super-types:	RegionType < SeparatorRegionType (by extension)
Sub-types:	None

Properties

Name	SeparatorRegionType
Abstract	no

Documentation

XML Instance Representation

<...
 id="xs:ID" [1]
 orientation="AngleType" [0..1]Attribute orientation

          Angle that the region has to be rotated in clockwise direction
          in order to correct the skew (negative values indicate
          anti-clockwise rotation). Range: (-180,180].
        
 
 
>
   <Property> PropertyType </Property> [0..*]
   <Coords> CoordsType </Coords> [0..1]
</...>

Schema Component Representation

<xs:complexType name="SeparatorRegionType">
   <xs:complexContent>
      <xs:extension base="RegionType"/>
   </xs:complexContent>
</xs:complexType>

Complex Type: TableRegionType

Type hierarchy

Super-types:	RegionType < TableRegionType (by extension)
Sub-types:	None

Properties

Name	TableRegionType
Abstract	no

Documentation

XML Instance Representation

<...
 id="xs:ID" [1]
 orientation="AngleType" [0..1]Attribute orientation

          Angle that the region has to be rotated in clockwise direction
          in order to correct the skew (negative values indicate
          anti-clockwise rotation). Range: (-180,180].
        
 
 
 rows="xs:int" [0..1]Attribute rows

              The number of rows present in the table.
            
 
 
 columns="xs:int" [0..1]Attribute columns

              The number of columns present in the table.
            
 
 
>
   <Property> PropertyType </Property> [0..*]
   <Coords> CoordsType </Coords> [0..1]
   <Word> WordType </Word> [0..*]
   <TextLine> TextLineType </TextLine> [0..*]
   <TextRegion> TextRegionType </TextRegion> [0..*]
   <SeparatorRegion> SeparatorRegionType </SeparatorRegion> [0..*]
</...>

Schema Component Representation

<xs:complexType name="TableRegionType">
   <xs:complexContent>
      <xs:extension base="RegionType">
         <xs:sequence>
            <xs:element name="Word" type="WordType" minOccurs="0" maxOccurs="unbounded"/>
            <xs:element name="TextLine" type="TextLineType" minOccurs="0" maxOccurs="unbounded"/>
            <xs:element name="TextRegion" type="TextRegionType" minOccurs="0" maxOccurs="unbounded"/>
            <xs:element name="SeparatorRegion" type="SeparatorRegionType" minOccurs="0" maxOccurs="unbounded"/>
         </xs:sequence>
         <xs:attribute name="rows" type="xs:int" use="optional"/>
         <xs:attribute name="columns" type="xs:int" use="optional"/>
      </xs:extension>
   </xs:complexContent>
</xs:complexType>

Complex Type: TextEquivType

Type hierarchy

Super-types:	None
Sub-types:	None

Properties

Name	TextEquivType
Abstract	no

Documentation

XML Instance Representation

<...
 type="NotEmptyType" [0..1]Attribute type

          The type of text, used to differentiate between multiple in the same
          element. For example, for n-best recognitions the type could be set
          as 'best1', 'best2', etc.
        
 
 
 conf="ConfType" [0..1]
 setBy="NotEmptyType" [0..1]
>
   <Property> PropertyType </Property> [0..*]
   <Unicode> NotEmptyType </Unicode> [1] 
</...>

Schema Component Representation

<xs:complexType name="TextEquivType">
   <xs:sequence>
      <xs:element name="Property" type="PropertyType" minOccurs="0" maxOccurs="unbounded"/>
      <xs:element name="Unicode" type="NotEmptyType"/>
   </xs:sequence>
   <xs:attribute name="type" type="NotEmptyType" use="optional"/>
   <xs:attribute name="conf" type="ConfType" use="optional"/>
   <xs:attribute name="setBy" type="NotEmptyType" use="optional"/>
</xs:complexType>

Complex Type: TextLineType

Type hierarchy

Super-types:	None
Sub-types:	None

Properties

Name	TextLineType
Abstract	no

Documentation

XML Instance Representation

<...
 id="xs:ID" [1]
>
   <Property> PropertyType </Property> [0..*]
   <Coords> CoordsType </Coords> [0..1]
   <Baseline> BaselineType </Baseline> [0..1]
   <Word> WordType </Word> [0..*]
   <TextEquiv> TextEquivType </TextEquiv> [0..*]
</...>

Schema Component Representation

<xs:complexType name="TextLineType">
   <xs:sequence>
      <xs:element name="Property" type="PropertyType" minOccurs="0" maxOccurs="unbounded"/>
      <xs:element name="Coords" type="CoordsType" minOccurs="0" maxOccurs="1"/>
      <xs:element name="Baseline" type="BaselineType" minOccurs="0" maxOccurs="1"/>
      <xs:element name="Word" type="WordType" minOccurs="0" maxOccurs="unbounded"/>
      <xs:element name="TextEquiv" type="TextEquivType" minOccurs="0" maxOccurs="unbounded"/>
   </xs:sequence>
   <xs:attribute name="id" type="xs:ID" use="required"/>
</xs:complexType>

Complex Type: TextRegionType

Type hierarchy

Super-types:	RegionType < TextRegionType (by extension)
Sub-types:	None

Properties

Name	TextRegionType
Abstract	no

Documentation

XML Instance Representation

<...
 id="xs:ID" [1]
 orientation="AngleType" [0..1]Attribute orientation

          Angle that the region has to be rotated in clockwise direction
          in order to correct the skew (negative values indicate
          anti-clockwise rotation). Range: (-180,180].
        
 
 
 readingDirection="ReadingDirectionType" [0..1]
>
   <Property> PropertyType </Property> [0..*]
   <Coords> CoordsType </Coords> [0..1]
   <Word> WordType </Word> [0..*]
   <TextLine> TextLineType </TextLine> [0..*]
   <TextEquiv> TextEquivType </TextEquiv> [0..*]
</...>

Schema Component Representation

<xs:complexType name="TextRegionType">
   <xs:complexContent>
      <xs:extension base="RegionType">
         <xs:sequence>
            <xs:element name="Word" type="WordType" minOccurs="0" maxOccurs="unbounded"/>
            <xs:element name="TextLine" type="TextLineType" minOccurs="0" maxOccurs="unbounded"/>
            <xs:element name="TextEquiv" type="TextEquivType" minOccurs="0" maxOccurs="unbounded"/>
         </xs:sequence>
         <xs:attribute name="readingDirection" type="ReadingDirectionType" use="optional"/>
      </xs:extension>
   </xs:complexContent>
</xs:complexType>

Complex Type: WordType

Type hierarchy

Super-types:	None
Sub-types:	None

Properties

Name	WordType
Abstract	no

Documentation

XML Instance Representation

<...
 id="xs:ID" [1]
>
   <Property> PropertyType </Property> [0..*]
   <Coords> CoordsType </Coords> [0..1]
   <Glyph> GlyphType </Glyph> [0..*]
   <TextEquiv> TextEquivType </TextEquiv> [0..*]
</...>

Schema Component Representation

<xs:complexType name="WordType">
   <xs:sequence>
      <xs:element name="Property" type="PropertyType" minOccurs="0" maxOccurs="unbounded"/>
      <xs:element name="Coords" type="CoordsType" minOccurs="0" maxOccurs="1"/>
      <xs:element name="Glyph" type="GlyphType" minOccurs="0" maxOccurs="unbounded"/>
      <xs:element name="TextEquiv" type="TextEquivType" minOccurs="0" maxOccurs="unbounded"/>
   </xs:sequence>
   <xs:attribute name="id" type="xs:ID" use="required"/>
</xs:complexType>

Simple Type: AngleType

Type hierarchy

Super-types:	xs:float < AngleType (by restriction)
Sub-types:	None

Properties

Name	AngleType
Content	Base XSD Type: float -180 < value <= 180

Documentation

Schema Component Representation

<xs:simpleType name="AngleType">
   <xs:restriction base="xs:float">
      <xs:minExclusive value="-180"/>
      <xs:maxInclusive value="180"/>
   </xs:restriction>
</xs:simpleType>

Simple Type: ConfType

Type hierarchy

Super-types:	xs:float < ConfType (by restriction)
Sub-types:	None

Properties

Name	ConfType
Content	Base XSD Type: float 0 <= value <= 1

Documentation

Schema Component Representation

<xs:simpleType name="ConfType">
   <xs:restriction base="xs:float">
      <xs:minInclusive value="0"/>
      <xs:maxInclusive value="1"/>
   </xs:restriction>
</xs:simpleType>

Simple Type: NotEmptyType

Type hierarchy

Super-types:	xs:token < NotEmptyType (by restriction)
Sub-types:	None

Properties

Name	NotEmptyType
Content	Base XSD Type: token length >= 1

Documentation

Schema Component Representation

<xs:simpleType name="NotEmptyType">
   <xs:restriction base="xs:token">
      <xs:minLength value="1"/>
   </xs:restriction>
</xs:simpleType>

Simple Type: PointsType

Type hierarchy

Super-types:	xs:string < PointsType (by restriction)
Sub-types:	None

Properties

Name	PointsType
Content	Base XSD Type: string pattern = ([-.0-9]+,[-.0-9]+ )+([-.0-9]+,[-.0-9]+)

Documentation

Schema Component Representation

<xs:simpleType name="PointsType">
   <xs:restriction base="xs:string">
      <xs:pattern value="([-.0-9]+,[-.0-9]+ )+([-.0-9]+,[-.0-9]+)"/>
   </xs:restriction>
</xs:simpleType>

Simple Type: ReadingDirectionType

Type hierarchy

Super-types:	xs:string < ReadingDirectionType (by restriction)
Sub-types:	None

Properties

Name	ReadingDirectionType
Content	Base XSD Type: string value comes from list: {'left-to-right'\|'right-to-left'\|'top-to-bottom'\|'bottom-to-top'}

Documentation

Schema Component Representation

<xs:simpleType name="ReadingDirectionType">
   <xs:restriction base="xs:string">
      <xs:enumeration value="left-to-right"/>
      <xs:enumeration value="right-to-left"/>
      <xs:enumeration value="top-to-bottom"/>
      <xs:enumeration value="bottom-to-top"/>
   </xs:restriction>
</xs:simpleType>

Glossary

Abstract (Applies to complex type definitions and element declarations). An abstract element or complex type cannot used to validate an element instance. If there is a reference to an abstract element, only element declarations that can substitute the abstract element can be used to validate the instance. For references to abstract type definitions, only derived types can be used.

All Model Group Child elements can be provided in any order in instances. See: http://www.w3.org/TR/xmlschema-1/#element-all.

Choice Model Group Only one from the list of child elements and model groups can be provided in instances. See: http://www.w3.org/TR/xmlschema-1/#element-choice.

Collapse Whitespace Policy Replace tab, line feed, and carriage return characters with space character (Unicode character 32). Then, collapse contiguous sequences of space characters into single space character, and remove leading and trailing space characters.

Disallowed Substitutions (Applies to element declarations). If substitution is specified, then substitution group members cannot be used in place of the given element declaration to validate element instances. If derivation methods, e.g. extension, restriction, are specified, then the given element declaration will not validate element instances that have types derived from the element declaration's type using the specified derivation methods. Normally, element instances can override their declaration's type by specifying an xsi:type attribute.

Key Constraint Like Uniqueness Constraint, but additionally requires that the specified value(s) must be provided. See: http://www.w3.org/TR/xmlschema-1/#cIdentity-constraint_Definitions.

Key Reference Constraint Ensures that the specified value(s) must match value(s) from a Key Constraint or Uniqueness Constraint. See: http://www.w3.org/TR/xmlschema-1/#cIdentity-constraint_Definitions.

Model Group Groups together element content, specifying the order in which the element content can occur and the number of times the group of element content may be repeated. See: http://www.w3.org/TR/xmlschema-1/#Model_Groups.

Nillable (Applies to element declarations). If an element declaration is nillable, instances can use the xsi:nil attribute. The xsi:nil attribute is the boolean attribute, nil, from the http://www.w3.org/2001/XMLSchema-instance namespace. If an element instance has an xsi:nil attribute set to true, it can be left empty, even though its element declaration may have required content.

Notation A notation is used to identify the format of a piece of data. Values of elements and attributes that are of type, NOTATION, must come from the names of declared notations. See: http://www.w3.org/TR/xmlschema-1/#cNotation_Declarations.

Preserve Whitespace Policy Preserve whitespaces exactly as they appear in instances.

Prohibited Derivations (Applies to type definitions). Derivation methods that cannot be used to create sub-types from a given type definition.

Prohibited Substitutions (Applies to complex type definitions). Prevents sub-types that have been derived using the specified derivation methods from validating element instances in place of the given type definition.

Replace Whitespace Policy Replace tab, line feed, and carriage return characters with space character (Unicode character 32).

Sequence Model Group Child elements and model groups must be provided in the specified order in instances. See: http://www.w3.org/TR/xmlschema-1/#element-sequence.

Substitution Group Elements that are members of a substitution group can be used wherever the head element of the substitution group is referenced.

Substitution Group Exclusions (Applies to element declarations). Prohibits element declarations from nominating themselves as being able to substitute a given element declaration, if they have types that are derived from the original element's type using the specified derivation methods.

Target Namespace The target namespace identifies the namespace that components in this schema belongs to. If no target namespace is provided, then the schema components do not belong to any namespace.

Uniqueness Constraint Ensures uniqueness of an element/attribute value, or a combination of values, within a specified scope. See: http://www.w3.org/TR/xmlschema-1/#cIdentity-constraint_Definitions.