IIIF Image API 2.0

IIIF Image API 2.0
Name	IIIF Image API 2.0
Released	2013
Developer	International Image Interoperability Framework
Latest version	2.1 (related)
License	Open standards

IIIF Image API 2.0 IIIF Image API 2.0 is a standardized HTTP-based interface for requesting image resources that enables interoperable image delivery across cultural heritage, research, and publishing institutions such as the British Library, Library of Congress, Smithsonian Institution, Bibliothèque nationale de France, and National Gallery, London. It defines request semantics used by repositories, aggregation services, and presentation software like Mirador, Universal Viewer, Europeana, Digital Public Library of America, and institutions including Harvard University, Yale University, Stanford University, Oxford University.

Overview

The specification was developed by stakeholders including members from Harvard University Library, J. Paul Getty Trust, Stanford University Libraries, Bibliothèque nationale de France, and Wellcome Trust to facilitate interoperable image access across platforms like GitHub, Apache Software Foundation hosted projects, and research infrastructures such as DuraSpace and OCLC. IIIF Image API 2.0 sits alongside other initiatives and standards such as International Image Interoperability Framework-related APIs used by Oxford University, Princeton University, University of California, Berkeley, National Library of Scotland, and Tate Modern.

Specification and Features

The 2.0 specification formalizes URL-based request parameters for region, size, rotation, quality, and format, enabling server implementations by projects like Cantaloupe (image server), IIPImage, Loris (image server), and integrations with systems at Europeana, DigitalNZ, National Library of Australia, New York Public Library. Features include support for tiled images used by viewers such as OpenSeadragon, and presentation frameworks employed by Metropolitan Museum of Art, Rijksmuseum, Museum of Modern Art, Vatican Library, and Getty Research Institute.

Image Requests and Parameters

Request URIs follow a path pattern that conveys region, size, rotation, quality, and format, used by digital repositories at British Library, Library of Congress, Smithsonian Institution and software projects like Mirador and Universal Viewer. Parameters provide precise control for supplying derivatives needed by platforms including Europeana, Digital Public Library of America, HathiTrust, Internet Archive, and academic projects at Yale University, Harvard University, Stanford University. Common query patterns are consumed by clients in environments such as Drupal, WordPress, Omeka, and by preservation systems at National Archives (UK), National Archives and Records Administration.

Supported Image Operations

IIIF Image API 2.0 describes operations for extracting regions (full, square, pixel coordinates), scaling and sizing (pct:, max), rotation (degrees, mirroring), quality selection (default, color, gray, bitonal), and output format negotiation (jpg, png, webp, tif) used by publishers like Wikimedia Foundation, BBC, The New York Times, The Guardian, and museums including Louvre, Prado Museum, Hermitage Museum. Servers implement tiling schemes supporting multi-resolution services employed by OpenSeadragon and mapping integrations like Leaflet in projects from Smithsonian Institution, National Library of Scotland, and Gallica.

Implementations and Servers

Notable server implementations include Loris (image server), IIPImage, Cantaloupe (image server), and commercial services integrated by Google Arts & Culture, Amazon Web Services, and aggregators like Europeana, Digital Public Library of America, Gallica, and Trove. Client libraries and tools exist in ecosystems tied to Python, Java, Node.js, and projects maintained by communities around GitHub repositories contributed to by teams from Harvard Library Lab, Stanford Libraries, British Library Labs, and technology partners such as Internet Archive.

Adoption and Use Cases

Adoption spans cultural heritage institutions such as British Library, Bibliothèque nationale de France, Vatican Library, National Gallery, London, and research centers at Harvard University, Yale University, Stanford University, and University of Oxford. Use cases include high-fidelity digitization programs at Metropolitan Museum of Art, Rijksmuseum, Smithsonian Institution, scholarly editions at Folger Shakespeare Library, educational portals like Europeana, and digital humanities projects supported by Andrew W. Mellon Foundation, National Endowment for the Humanities, and Horizon 2020 grants.

Compatibility and Migration from 1.x

Migration guidance supported large-scale adopters including British Library, Bibliothèque nationale de France, Library of Congress, National Library of Scotland, and repositories at Stanford University to transition implementations and clients such as Mirador and Universal Viewer from the 1.x path and parameter forms to 2.0 semantics. Compatibility considerations influenced tooling at GitHub-hosted projects and institutional deployments at Harvard University, Yale University, Oxford University, and libraries participating in consortia like DPLA, Europeana, and OCLC.

Category:APIs