Commons:Machine-readable data

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On Wikimedia Commons, a lot of metadata (including license and author) are not machine readable. There is an API module, iiprop=extmetadata which can be used to retrieve some values (example), but as the information is entered as free text into the file description page itself, this is not perfect. The ongoing Structured data on Commons project aims to move the metadata as fully-structured data and will eventually supersede the machine-readable data presented in this page.

In the meantime, and to ease a transition towards more structured data at a future time, Wikimedia Commons use a set of standard templates which have been made machine-readable in some ways, through HTML elements. Some scripts already make use of that. It is worth noting that this data is available for any wiki using Wikimedia Commons, where it can be read from the html of the File: page just as other local data.

Machine readable data

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Machine readable data set by infobox templates

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These are several standard infobox templates tagging different elements of the template with different tags to allow parsing of the information. Several different styles of tags are used:

  • Microformat tags follow industry standards and can be parsed by already existing tools.
  • <td> id attributes (identifiers) are custom markings which allow more complete tags, which have to be read by custom tools. Most universal infoboxes have two column structure: column #1 holds name of the field and column #2 holds the value
    • Traditionally <td> id attributes were used to tag the name call in the first column in a row. To get the data, you would need to get the contents of the following <td> cell in the second column.
    • {{Creator}} and {{Institution}} templates have more complicated structure, so the cells with the actual data are tagged with attributes using magenta background.
Template Template parameter name Description <td> id attribute Microformat Comment
{{Information}} description file description fileinfotpl_desc hProduct.description. Often contains multiple languages annotated with {{Lang}}.
{{Information}} date date the original work was created fileinfotpl_date hCalendar vevent.dtstart Sometimes additionally, or only, contains publication date. These two dates have different meanings for copyright. When used, {{Date context}} can indicate the difference. Microformat added by {{Date}} template
{{Information}} source file's source fileinfotpl_src Often contains entire tables. We have no good way to deal with this source templates yet. Source templates often have references to catalogue IDs, but these are also not machine readable.
{{Information}} author file's author fileinfotpl_aut This can be author, creator and/or copyright holder and is used mixed. Often contains the {{Creator}} template which is described below.
{{Information}} permission permission/license for the file fileinfotpl_perm
{{Information}} other versions other versions of the file fileinfotpl_ver
{{Artwork}} description description of the artwork fileinfotpl_desc hProduct.description
{{Artwork}} date date of creation of the original artwork fileinfotpl_date hCalendar vevent.dtstart microformat added by {{Date}} template
{{Artwork}} source file's source fileinfotpl_src
{{Artwork}} artist creator of the artwork fileinfotpl_aut "hProduct.fn value"
{{Artwork}} author author of the artwork fileinfotpl_aut "hProduct.fn value"
{{Artwork}} permission permission/license for the file and artwork fileinfotpl_perm
{{Artwork}} other versions other versions of the file fileinfotpl_ver
{{Artwork}} title title of the artwork fileinfotpl_art_title hProduct.fn
{{Artwork}} object type artwork object type fileinfotpl_art_object_type
{{Artwork}} medium technique or medium of the artwork fileinfotpl_art_medium
{{Artwork}} dimensions dimensions of the artwork fileinfotpl_art_dimensions
{{Artwork}} gallery institution holding the artwork fileinfotpl_art_gallery
{{Artwork}} location location of the artwork within the institution fileinfotpl_art_location hProduct.locality
{{Artwork}} accession number accession number of the artwork fileinfotpl_art_id hProduct.identifier
{{Artwork}} object history object history of the artwork fileinfotpl_art_object_history
{{Artwork}} exhibition history exhibition history of the artwork fileinfotpl_art_exhibition_history
{{Artwork}} credit line credit line of the artwork fileinfotpl_art_credit_line
{{Artwork}} inscriptions inscriptions on the artwork fileinfotpl_art_inscriptions
{{Artwork}} notes notes about the artwork fileinfotpl_art_notes
{{Artwork}} references references related to the artwork fileinfotpl_art_references
{{Book}} Author author of the book fileinfotpl_author
{{Book}} Editor editor of the book fileinfotpl_book_editor
{{Book}} Translator translator of the book fileinfotpl_book_translator
{{Book}} Illustrator illustrator of the book fileinfotpl_book_illustrator
{{Book}} Title title of the book fileinfotpl_book_title
{{Book}} Subtitle subtitle of the book fileinfotpl_book_subtitle
{{Book}} Series title series-title of the book fileinfotpl_book_series-title
{{Book}} Authority file authority control data fileinfotpl_book_authority
{{Book}} Publisher publisher of the book fileinfotpl_book_publisher
{{Book}} Printer printer of the book fileinfotpl_book_printer
{{Book}} Year of publication date or year of the publication of the book fileinfotpl_date
{{Book}} Place of publication place or city of the publication of the book fileinfotpl_book_place-of-publication
{{Book}} Language language of the book fileinfotpl_book_language
{{Book}} Description description of the book fileinfotpl_desc
{{Creator}} Name Name of creator creator vCard.fn
{{Creator}} Alternative names Alternative names of creator fileinfotpl_creator_alt-name_value vCard.nickname
{{Creator}} Description Nationality and occupation(s) of creator fileinfotpl_creator_desc_value vCard.note
{{Creator}} Date of death Date of death of creator fileinfotpl_creator_deathdate_value
{{Creator}} Date of birth Date of birth of creator fileinfotpl_creator_birthdate_value vCard.bday
{{Creator}} Location of birth/death Location of death of creator fileinfotpl_creator_deathloc_value
{{Creator}} Location of birth Location of birth of creator fileinfotpl_creator_birthloc_value
{{Creator}} Work period Work period of creator fileinfotpl_creator_work-period_value
{{Creator}} Work location Work location of creator fileinfotpl_creator_work-location_valuev
{{Creator}} Image portrait or photo showing the creator fileinfotpl_creator_image
{{Creator}} Authority file Authority control related to the creator fileinfotpl_creator_authority_value


{{FileContentsByBot}} (various) depends, please confer {{FileContentsByBot}} (various) hproduct-by-bot big data set and still growing, please confer {{FileContentsByBot}}
{{Photograph}} title title of the photograph fileinfotpl_art_title hProduct.fn
{{Photograph}} description description of the photograph fileinfotpl_desc hProduct.description
{{Photograph}} original description original archival description of the photograph fileinfotpl_desc hProduct.description
{{Photograph}} date date of creation of the original artwork fileinfotpl_date hCalendar vevent.dtstart microformat added by {{Date}} template
{{Photograph}} medium technique or medium of the photograph fileinfotpl_art_medium
{{Photograph}} dimensions dimensions of the photograph fileinfotpl_art_dimensions
{{Photograph}} artist creator of the photograph fileinfotpl_aut "hProduct.fn value"
{{Photograph}} institution institution holding the artwork fileinfotpl_art_gallery
{{Photograph}} location location of the photograph within the institution fileinfotpl_art_location hProduct.locality
{{Photograph}} source file's source fileinfotpl_src
{{Photograph}} permission permission/license for the file and artwork fileinfotpl_perm
{{Photograph}} other versions other versions of the file fileinfotpl_ver
{{Photograph}} accession number accession number of the photograph hProduct.identifier

Alternative format for CommonsMetadata

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Because the table + id based format proved very hard to add to templates which were not formatted similarly to the Commons information template, CommonsMetadata allows an alternative format, similar to license templates: the whole information template has to be enclosed in a fileinfotpl class and the tag containing the specific information needs to have a fileinfotpl_* class (same names as above, but class, not id).

Machine readable data set by license templates

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Introduced in October 2010, using classes <span class="licensetpl_XXX">

licensetpl
An element identifying a license. Wraps the entire license code and should be a SINGLE license, not a multi license.
licensetpl_short
Short name of the license: “Public domain”, “CC BY-SA 3.0”, “CC by 2.0 fr”, etc.
licensetpl_long
Long name of the license: “Public domain”, “Creative Commons Attribution-Share Alike 3.0”,
licensetpl_attr_req
Whether attribution is required. “true” or “false”.
licensetpl_attr
The requested attribution: Free text.
licensetpl_link_req
Whether a link to the license is required for this license. “true” or “false”.
licensetpl_link
The link to the license deed. “www.creativecommons.org/licenses/by-sa/XXX/YYY”
licensetpl_nonfree
“true“ if this is a non-free license (not used on Commons, only on wikis with an EDP)

Multiple licensetpl blocks for the same work might be wrapped in a block using the class licensetpl_wrapper.

Templates setting this information

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Machine readable data set by style formatting templates

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Style formatting templates, meant to provide uniform styles to different families of non-license templates, carry machine readable data identifying these families.

Template Purpose class name
{{Restriction-Layout}} used by Restriction tags restrictiontemplate
{{FoP-Layout}} used by freedom of panorama tags foptemplate
{{Partnership-Layout}} used by Partnership templates partnershiptemplate
{{Source-Layout}} used by generic Source templates sourcetemplate
{{Created with}} used by Created with ... templates createdwithtemplate
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Templates regarding non-copyright legal restrictions carry these classes to identify specific types of restrictions.

Template(s) Purpose class name
{{Trademarked}} Trademarked images restriction-trademarked
{{Copydesign}} Copyrighted designs restriction-design
{{Communist symbol}} Communist symbols restriction-communist
{{Italy-MiBAC-disclaimer}} {{Soprintendenza}} Italian cultural goods restriction-ita-mibac
{{Australian Commonwealth reserve}} Australian reserves restriction-aus-reserve
{{Personality rights}} {{Romania personality rights}} Personality rights restriction-personality
{{2257}} Child Protection and Obscenity Enforcement Act warning (United States) restriction-2257
{{Costume}} Costuming restriction-costume
{{Fan art}} Fan art restriction-fan-art
{{Currency}} Currency restriction-currency
{{IHL Symbol}} Symbols restricted by International Humanitarian Law restriction-ihl
{{Nazi symbol}} Nazi and fascist symbols restriction-nazi
{{Insignia}} Official insignia restriction-insignia

Machine readable data set by specific templates

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More machine-readable data are set. Here is a non-exhaustive list:

{{Personality rights}}
<span class="commons-template-name" style="display:none" id="commons-template-personality-rights">Personality rights</span>
{{Credit line}}
<td id="fileinfotpl_credit" class="fileinfo-paramfield fileinfotpl_credit" style=""></td>

Machine-readable data set by location templates

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{{Location}} and similar templates add machine-readable geocodes in the following format: <span class="geo">12.34;24.68</span> (latitude and longitude as floating-point numbers, separated by a semicolon). The coordinates use the en:WGS84 system (same as the GPS and most online maps). See Commons:Geocoding for more details.

Usage

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MediaWiki API

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The MediaWiki API now serves a limited number of metadata. Consider the following query:

/w/api.php?action=query&prop=imageinfo&format=json&iiprop=extmetadata&iilimit=5&titles=File%3AFranziskanerkirche%20Salzburg%20panoramic%20view%20interior%2039252px.jpg

(Open in API Sandbox) that returns some useful parameters such as Credit, Artist, LicenseUrl and Copyrighted and is used by Media Viewer, for example.

Scripts using machine-readable data

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External tools

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See also

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Defining new machine readable data

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  • Do NOT use HTML id's, use classes. An ID can only be used once per page and most of these fields can occur multiple times per page. Consider for instance descriptions of derivative works, which can include information about the original and the derivative.
  • When possible, wrap the actual data, not some field header. This last method is historically used for all our Information templates, but much harder to support in the long run.
  • Wrap data, not the way the data is formatted.
  • Expect that formatting is lost when converting to data. Visual dress up is not part of the information.
  • Don't wrap multiple units of information inside one field. There is a difference between a publication date and a creation date. Both are dates, but both are different 'data fields'. Also CC BY-SA-4.0-3.0-2.5 is not a license name, those would be 3 licenses with the name CC BY-SA-##.
  • Make sure that the data value has one unit, or outputs one consistent unit.

Problems

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There are a few things that are currently NOT or badly recognizable. These include: