Range

Some works such as books, compound objects, or complex audio visual works may have a hierarchy that describes the various sections and subsections of an item. By creating a Range to represent each section and subsection, a viewer can leverage this data and provide users a way to navigate across a work using each these resources.

The PCDM Works Extension defines multiple two classes for modelling this type of data: pcdmworks:TopRange and pcdmworks:Range. These classes were informed by the IIIF Presentation API. Prior to version 3 of the API specification, the top most Range required a viewingHint="top" property, and the pcdmworks:TopRange class provided a way to distinguish between the two. As of version 3.0 of the API, this requirement is no longer needed and thus we do not need both classes.

Minimum Model

A simple Range may have many more properties, but should look something like this:

@prefix ex: <http://example.org/> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix pcdm: <http://pcdm.org/models#> .
@prefix pcdmworks: <http://pcdm.org/works#> .

ex:Range a pcdmworks:Range ;
    rdfs:label "An Example Top Level Range" ;
    pcdm:memberOf ex:Work ;
    pcdm:hasMember ex:FileSet .

Rules and Guidelines

A Proxy MUST:

  • be an instance of pcdmworks:Range via the rdf:type property.

  • be related to a parent Work via pcdm:memberOf or pcdm:hasMember.

  • be related to a pcdmworks:FileSet or other pcdm:Object instance via pcdm:hasMember.

  • have a label in a property like rdfs:label unless its not intended for viewing. This requirement comes from IIIF presentation’s requirement for client viewers making use of these concepts.

  • use iana properties and ore:Proxy classes for ordering of the ranges.

A Proxy MAY:

  • have other descriptive metadata properties.

Real World Examples

A Book with Minimal Hierarchy

This object builds off the example in the proxy section, but eliminates some nodes including the pcdm:File resources, the parent book, and a couple of referenced chapters to make the relevant parts of this example easier to understand.

For full examples of a completed object, see the work-types or recipes section.

@prefix ex: <http://example.org/> .
@prefix iana: <http://www.iana.org/assignments/relation/> .
@prefix ore: <http://www.openarchives.org/ore/1.0/datamodel#> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix pcdm: <http://pcdm.org/models#> .
@prefix pcdmworks: <http://pcdm.org/works#> .
@prefix pcdmuse: <http://pcdm.org/use#> .
@prefix pcdmff: <http://pcdm.org/file-format-types#> .
@prefix fedora: <http://fedora.info/definitions/v4/repository#> .

# This is a Proxy for Page 1 that will be Canvas 1 in a IIIF Manifest and is the Front Cover
ex:ProxyForPageOne a ore:Proxy ;
    ore:proxyIn ex:BookWork ;
    ore:proxyFor ex:BookPageOneFileset ;
    iana:next ex:ProxyForPageTwo .

# This is a Proxy for Page 6 that will be Canvas 6 in a IIIF Manifest and is the start of Chapter 1
ex:ProxyForPageSix a ore:Proxy ;
    ore:proxyIn ex:BookWork ;
    ore:proxyFor ex:BookPageSixFileset ;
    iana:prev ex:ProxyForPageFive ;
    iana:next ex:ProxyForPageSeven .

# This is a Proxy for Page 33 that will be Canvas 33 in a IIIF Manifest and is the back cover
ex:ProxyForPageThirtyThree a ore:Proxy ;
    ore:proxyIn ex:BookWork ;
    ore:proxyFor ex:BookPageThirtyThreeFileset ;
    iana:prev ex:ProxyForPageThirtyTwo .

# This is a Fileset that includes the files used by Canvas 1 in the presentation manifest.
ex:BookPageOneFileset a pcdmworks:Fileset ;
    rdfs:label "Page One" ;
    pcdm:memberOf ex:BookWork ;
    pcdm:hasFile ex:Image, ex:HOCR, ex:OCR .

# This is a Range that represents the Front Cover of a Book and points to the page 1 fileset
ex:FrontCover a pcdmworks:Range ;
    rdfs:label "Front Cover" ;
    pcdm:memberOf ex:BookWork ;
    pcdm:hasMember ex:BookPageOneFileset .

# This is a Proxy for the front cover range in a IIIF Manfiest
ex:ProxyForFrontCover a ore:Proxy ;
    ore:proxyIn ex:BookWork ;
    ore:proxyFor ex:FrontCover ;
    iana:next ex:ChapterOne .

# This is a Range that represents Chapter 1 of a Book and points to the page 6 fileset
ex:ChapterOne a pcdmworks:Range ;
    rdfs:label "Chapter One" ;
    pcdm:memberOf ex:BookWork ;
    pcdm:hasMember ex:BookPageSixFileset .

# This is a Proxy for the chapter one range in a IIIF Manfiest
ex:ProxyForChapterOne a ore:Proxy ;
    ore:proxyIn ex:BookWork ;
    ore:proxyFor ex:ChapterOne ;
    iana:next ex:ChapterTwo .

# This is a Range that represents Chapter 33 of a Book and points to the page 33 fileset
ex:BackCover a pcdmworks:Range ;
    rdfs:label "Back Cover" ;
    pcdm:memberOf ex:BookWork ;
    pcdm:hasMember ex:BookPageThirtyThreeFileset .

# This is a Proxy for the back cover in a IIIF Manfiest
ex:ProxyForBackCover a ore:Proxy ;
    ore:proxyIn ex:BookWork ;
    ore:proxyFor ex:BackCover ;
    iana:prev ex:ChapterThree .

A Book with Complex Hierarchy

We need a more complex example as the above likely won’t work for places like National Library of Wales.