IIIFarm. Teaching Image Interoperability on a Raspberry Pi Network of IIIF-Compliant Image Servers.

This paper will discuss a two-and-a-half-day workshop on IIIF, the ‘International Image Interoperability Framework’ that the authors designed and tutored as part of a summer school on analyzing and processing images in Digital Humanities. Across GLAM-institutions (Galleries, Libraries, Archives, and Museums) and image-based Digital Humanities projects, IIIF’s set of shared API (Application Programming Interface) specifications is quickly becoming a standard for enabling interoperability functionality in digital image repositories around the world. Hosting images on a IIIF-compliant image server makes it much easier to parse and share digital image data, migrate them across technology systems, and provide enhanced access to them for scholars, researchers, and general users. Essentially, IIIF allows for the possibility of opening up image collections for extensive sharing and reuse, and all without losing  web-traffic on the host institution’s web servers.
Although the benefits of using IIIF for research and reuse purposes should not be underestimated, the concept behind IIIF is abstract and its implementation can be technically daunting. As such, the complexity of the technology may lead to some hesitancy on the part of representatives of cultural heritage institutions to make the change for their digital image collections. That is further complicated by the fact that IIIF seminars and workshops usually (in our anecdotal experience at least) do not have the time for anything but scratching the surface of the technology’s possibilities: such workshops try to explain the basic concept behind IIIF, show some of the API’s powerful parameters, and let participants play around with IIIF Image Viewers such as Mirador and UniversalViewer. Since we believe that convincing potential users of the real benefits of IIIF requires more of an engagement on the part of the user, we designed a hands-on workshop in order to immerse our participants in the topic: instead of just using the technology, we would take our time and teach the students how the technology works, and how they could install and configure it themselves.
The aims of the tutorial were straightforward: first, we wanted to help the students set up their own IIIF compliant image servers; and then, taking it one step further, we wanted to let them collect and reuse each other’s images. This would introduce students to the technology behind IIIF and allow them to unlock its full potential in a classroom setting where they had ready access to help from the tutors. In the course of the workshop, we distributed images of random pages of a single document for the students to host and share on their image servers. In the end, we would teach them how to create a manifest that would link the document’s distributed pages together, and that they could feed into a IIIF Image Viewer to bring their images together in a nice presentation environment. For the teaching materials, we used the draft manuscript of Mary Shelley’s Frankenstein that the Bodleian had recently released on its IIIF-compatible Digital Library. Using the Frankenstein metaphor as a didactic instrument, the class was told they would be assembling their own ‘monster’ from a series of unconnected parts. To get there, however, we needed to introduce some basic related technologies to our students, particularly because the course was open to students with no prior knowledge of IIIF or command line computing. But before we could do that, we first needed the hardware for the students to put their image servers on.
That hardware consisted of a gigabit router, further networking hardware, and 15 monitors, keyboards, and Raspberry Pi 3 mini computers. Thanks to the generous support of DARIAH-BE, we were able to acquire enough of these devices to provide every group of two to three students with a credit card sized mini server for the duration of the course. As inexpensive and low-power computers, Raspberry Pis are especially helpful in areas where people face significant constraints on power, network capacity, finances, etc. Using Raspberry Pis also provided us with a useful segue to introduce the students to minimal computing – a subfield of Digital Humanities that aims to rethink DH work for areas in the world where these factors are not a given, or where we want to make less of an impact on our environment. Moreover, Connecting these Raspberry Pis over a local network to turn them into a mini server farm also offered the students a practical way to learn more about and play with fundamental computing concepts. In particular, the students were exposed to issues in physical computational and networking infrastructures; operating a computer without an interface (command line); and communicating with and controlling other computers (in a very similar way to real world server solutions).
After setting up their Raspberry Pis, linking them together in an offline network (our ‘IIIFarm’), and hacking a solution for connecting their server to the internet as well, the students disconnected them from their monitors and keyboards, and used SSH (secure shell) on their own laptops to configure their image servers remotely over WiFi. Practicing some basic commands that they had learned at the summer school only the day before, they now downloaded, created and edited new files on their Raspberry Pis; wrote a web-page in HTML; installed an Apache web server to make it accessible to the rest of the class; converted their high-resolution images to Pyramid TIFFs; and installed a IIIF-compatible image server to share those images with each other as well. Moreover, they performed these tasks via their own laptops’ CLI (command line interface), and turned their Raspberry Pi monitors on as little as possible. When the students achieved these steps, we gave them a short introduction to JSON, which allowed them to read and edit IIIF manifests, and mix together each other’s images using a Mirador viewer that we had installed on a separate Raspberry Pi on the network, where they could behold the ‘little monsters’ they had created.
Throughout the course, we applied the didactic concept of experiential learning. Every step of the configuration process had to be executed individually by the participants, giving them enough opportunities to make mistakes and to learn from them. This was also true for the instructors: this was the first time we had taught this course, and we were fine-tuning it, incorporating the students’ problem solutions and fixing bugs as we were teaching it. Since we had never tested building a network with fifteen Raspberry Pis, we were as happy as the students when they succeeded just in time for the end of the workshop.
In this paper, we will start with situating the workshop in the context of the summer school. After introducing the setting, concept, setup, and structure of the course in a little more detail, we will present some of the key lessons we learned organizing and teaching this course. To achieve this we will focus on some of the infrastructure, network, hardware, and software issues we encountered, and disclose how we tried to solve or circumvent those problems. In addition, we will report on the feedback we received from our students (on the course itself, as well as in relation to the rest of the summer school) which they submitted to us anonymously. We will then reflect on how a hands-on and in-depth treatment of a concept as complex and relevant as IIIF can be as rewarding for the teacher as it is for the student. In that spirit, we will end by presenting the tutorial we are currently developing on the basis of this workshop, and which will be available for reuse at the time of the conference.