IIIF and Hydra Works

Owned by Bill Branan
Jun 16, 2017
1 min read

Discussion:

  • Hydra:Collection maps to IIIF:Collection
  • Hydra:Work maps to IIIF:Manifest
  • IIIF:Sequence is derived from the Ordering of the Work
  • Hydra:Work (representing a part of another work, at arbitrary depth) maps to IIIF:Canvas
  • Hydra:File (where the content is an Image) is the Image, annotated on to the CanvasĀ 

The objects in Hydra could provide their JSON-LD representation.

Noted that IIIF:Canvas needs to know its height and width, but other than that the only required metadata are labels on the Manifest and Canvas. Ā Height and width can be derived from the h/w of the depicting image, which could be retrieved from the IIIf info.json response. Ā This could be slow, so should only be done once and thus ...Ā 

We discussed speedĀ ā€“ it's slow to walk through 500 pages. Ā The solution was to cache the responses as they only change when the resource is changed. Ā Could be done at the Varnish level, or lower in the stack. Ā 

Noted the distinction between Image API's info.json response, which is technical information about the IIIF:Image / Hydra:File, and the Presentation API JSON-LD content, which is the descriptive, rights and structural metadata, as in the above mapping.

Actions:

  • Colin and Trey to investigate how to build it. Ā Ideas included RIIIF or exporting to IIP/Loris.Ā 
  • Also noted to look at OSullivan from Stroop:Ā https://github.com/jpstroop/osullivan