1 The International Image Interoperability Framework, or IIIF,1 has been taking the digital libraries world by storm. This Linked Open Data initiative defines APIs for retrieving, tiling, organizing, annotating, and searching high resolution images from digital collections. A community of developers, librarians, and researchers has formed around the standard, making it a success and developing implementations of the APIs (such as Mirador2 and the Universal Viewer).3 The integration of TEI and IIIF is a natural consequence, particularly for the many TEI-based editions that present primary source images alongside TEI transcriptions. This paper will present an overview of current approaches to this integration and describe the solution currently being implemented at the Shelley-Godwin Archive (S-GA).4

2 The IIIF Presentation API adopts the Open Annotation standard (a W3C recommendation),5 which makes it possible to connect resources of different kinds (including text) to any parts of an image. Existing projects, such as the Scholastic Commentaries and Texts Archive,6 use this system to “annotate” facsimile images with TEI transcriptions. Typically, this is done by extracting the relevant portion of text from a TEI document and including it as plain text with markup in the IIIF manifest (a collection of triples). This approach plays well with IIIF tools, as it makes it possible, among other things, to show text over images. However, separating snippets of a TEI document from their context reduces their usefulness: for example, references from the text to the TEI header would be meaningless without the header. The solution currently being developed by S-GA annotates IIIF images with selectors pointing to parts of TEI-encoded texts. By following the selectors, clients can display and manipulate TEI-encoded text with access to the complete TEI document. This essentially emulates, in a IIIF-friendly way, TEI’s approach to digital facsimile described in Chapter 11 of the TEI Guidelines.