Thursday, January 10, 2019

Updates to IIIF image annotation in the EADitor back-end

The American Numismatic Society's archival images were migrated into IIIF in the fall of 2017, including the extension of EADitor to faciliate the creation of manifests from TEI files that represent the Newell notebooks. While the front end was updated to use Leaflet for single photographs (MODS records) or Mirador for image collections, like the notebooks or the Agnes Balwin Brett papers, the back-end had not been updated to enable the editing or creation of new annotations.

After the back-to-back releases of the full Seleucid Coins Online and the first phase of Ptolemaic Coins Online in December, I have been able to pivot completely from coin type corpora and data cleaning to working on our digital archives for a brief period. After fixing some bugs, I turned my attention to piecing the image annotation back together in the XForms engine for TEI editing/publication within Archer. The original system was developed in 2014. This blog post covers most of the technical underpinnings, but to summarize: Rainer Simon's Annotorious was hooked into OpenLayers to facilitate image annotation. The create/remove/update handlers in Annotorious were used to round trip the annotations to/from TEI surface elements within tei:facsimiles and Annotorious' JSON model in the XForms engine (using the client-side Javascript hooks in Orbeon). There have been significant updates to Orbeon since 2014, and my original code was somewhat broken, and therefore I needed to explore alternative solutions.

My first attempt was loading a manifest for a Newell notebook into Mirador in the XForms web form. Although Mirador did load the manifest, due to of some unforeseen conflicts between the Javascript in Orbeon and Mirador, the annotation popups (with the TinyMCE library) didn't function correctly. I then began to explore Masahide Kanzaki's Image Annotator. This was appealing, as I had tested this application's ability to show two images on the same canvas in dynamically SPARQL-generated IIIF manifests from Numishare-based type corpora (see this example of RRC 15/1a that combines IIIF images from three different museums into one manifest--one canvas per coin and two images per canvas). The Image Annotator not only loads IIIF manifests into OpenSeaDragon, but was extended to support Annotorious for creating and viewing annotations.

After several days of work, I have been able to fully reactivate image annotation in the EADitor back-end with the Image Annotator. It took a little bit of reverse engineering in order to find the functions for the handlers, with some slight modifications to my original code to hook the Annotorious handlers into the XForms engine. This included some changes in the mathematical calculations for converting the ratio-based coordinates to pixels for the TEI surface's upper-left x,y and lower-right x,y attributions. These TEI attributes are serialized into proper #xywh fragments in the Web Annotations in the manifest.


Fig. 1: Image Annotator in the XForms engine

I also had to track down and comment out some components of the UI (like the document metadata and links) and tweak the CSS so that the OpenSeaDragon window fit within the parameters of my existing Bootstrap 3.x template.

URIs in certain namespaces are still parsed to extract human-readable labels (see Fig. 1 and 2), for example, from the ANS collection. My intention is to extend the range of parseable URIs to include Wikidata, other URIs in the ANS digital library or archives, Social Networks and Archival Context, Worldcat Works, and, eventually, URIs for Hellenistic monograms. I might even extend the parsing to extract thumbnail images for coins and store those in the tei:desc within the TEI document (in addition to simple mixed content w/ tei:ref elements as external links).

Fig. 2: After clicking 'Save', the URI is replaced with an HTML link

After the reworking of the IGCH data over the next several months, we will turn our attention to annotating more of Edward T. Newell's notebooks as part of the NEH-funded Hellenistic Royal Coinages (HRC) project. The UI provided by the Image Annotator is much easier to work with than the one I had developed more directly within XForms nearly five years ago, and so we should see some significant progress toward annotation these notebooks to link to coins in our (or other) numismatic collections, coin types in HRC, Greek coin hoards, and our yet-to-be-published database of Greek monograms. And these annotations will enhance research context in our other platforms by pointing users back to individual notebook pages in Archer from Mantis or IGCH (for example, from http://coinhoards.org/id/igch1664 or http://numismatics.org/collection/1944.100.26870).

SPARQL-generated list of Open Annotations related to IGCH 1664

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