Streamlining Text Encoding Initiative (TEI), International Image Interoperability Framework (IIIF), and Mirador: Theoretical and Practical Considerations for Interactive Critical Editions

The utility of the Text Encoding Initiative Guidelines for encoding texts suitable for production of critical editions is well established (Burghart 2017). In the past, those have been substantially static editions in print or online (Driscoll and Pierazzo 2016). Meanwhile, the dominant set of standards for presenting images of manuscripts is the International Image Interoperability Framework (IIIF). The most popular viewer based on IIIF is Mirador. With the essential information encoded according to IIIF standards, Mirador can display images of manuscripts with multiple image layers per page and annotations of transcriptions and descriptions. There are practical and theoretical challenges in producing an edition with all the advantages of each. For one, they use different languages. TEI uses eXtensible Markup Language (XML), while IIIF uses JavaScript Object Notation (JSON). The deeper difference is in how a text is conceptualized and structured. TEI, properly used, asks us to think of texts as abstractions with divisions, paragraphs, sentences, and words. IIIF asks us to think about a manuscript as a sequence of canvases of pages. Annotations are mapped to  x and  y coordinates on those pages. These challenges can, however, be surmounted. In fact, TEI can encode all the information that would be necessary to derive a IIIF Presentation manifest and annotations for each line of a manuscript. There are several benefits of centralizing work on a manuscript in TEI and automatically deriving IIIF information. First, a scholar is asked to master only one language and one set of guidelines. TEI is not necessarily easy to master, but the guidelines are consistent and all in one place. Second, there is no duplication of information pertinent both to critical editions and an interactive manuscript viewer. For example, the transcription of the text is only edited once. We avoid conflicts that arise when one file is updated and not another. Third, just as the complexity of human-edited source files is reduced, so too the complexity of project team can be reduced. It is not at all implausible that a single scholar could learn the necessary TEI standards and have little or no need for technical collaborators. Collaboration of large teams certainly has advantages for projects funded by government grants and large institutions. A simpler model, however, is accessible to individual scholars with little or no funding (Pierazzo 2019). In that way, the streamlined minimal computing approach described here addresses the conference theme of “addressing global inequities in access to technology.”

Specifically, the streamlining of TEI, IIIF, and Mirador will be discussed with reference to the Jubilees Palimpsest Project and the NEH-funded production of a scholarly edition. The text being encoded and presented is a palimpsest recovered with multispectral imaging technology. For that reason, there is no one all-sufficient facsimile image of a page that could be printed as a plate in a print edition. IIIF has the ability to include many image layers on a single canvas, and Mirador has tools for showing those layers. Additional layers with raking illumination illustrate the texture of the image, including evidence of the production and condition of the folios. Even with multispectral imaging technology, the erased text is not so legible that a reader would not need editorial guidance on region and proposed transcription. In the past, a manuscript too difficult for a facsimile edition would be presented only as an edited text. The reader would be asked to accept the editor’s authority for crucial readings. The reader would have no experience of the manuscript as anything other than a text container. The physical reality of the scribal cultures that produced and used a manuscript would be lost in transmission. At the same time, a digital experience of the manuscript without the expertise of editors would not suffice. All the information traditionally encoded in TEI for the production of a static critical edition can stand beside the additional information necessary to visualize the manuscript facsimile in folios, columns, and lines of text. The paper will demonstrate the proper TEI elements for encoding the information necessary for IIIF, including facsimile, graphic, line, zone, page beginning, line beginning, and various milestones. Examples from the Jubilees Palimpsest Project use XSLT for transformation from TEI XML to IIIF JSON. The same concepts can be implemented in other languages such as Python or platforms such as TextGrid and the University of Pisa’s Edition Visualization Technology.

Appendix A

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Todd R. Hanneken (thanneken@stmarytx.edu), St. Mary’s University (San Antonio), United States of America