G'day Ben!

My understanding of the IIIF Presentation APIs and TEI facsimiles is that
the equivalences are:

   - IIIF Collection = <tei:teiCorpus>
   - IIIF Manifest = <tei:TEI> containing a <tei:facsimile>
   - IIIF Canvas = <tei:surface> or <tei:surfaceGroup>
   - A IIIF "Image annotation" on an IIIF Canvas = a <tei:graphic> element
   in a <tei:surface>.
   - A IIIF Image annotation that refers to a sub-region of a Canvas = a
   <tei:graphic> inside a <tei:zone> which is inside a <tei:surface>. In IIIF
   the region of the annotation is given in a URI fragment identifier (e.g.
   #xywh=0,0,500,500); the corresponding <tei:zone> has attributes which
   specify a bounding box or polygon as a sequence of X,Y points.
   - A IIIF annotation which isn't an image could correspond to various
   things in TEI: simple comments attached directly to an image would be
   modelled in TEI as <tei:desc>  or <tei:label> elements within the
   <tei:surface> or <tei:zone>.

Slightly more complex is the notion of ordering:

   - IIIF Sequences and Ranges model the logical ordering and arrangement
   of the Canvases. In TEI, the <tei:surface> elements obviously fall in an
   order in the XML file, but TEI users would usually consider that the
   logical arrangement of <tei:surface> elements is given by the logical order
   of the textual transcription, inside the tei:body element. In TEI, the
   <surface> elements are generally linked explicitly to <pb> (page break)
   elements in the TEI transcription. So in that sense, the TEI textual
   transcription really plays the role that Sequences and Ranges do in IIIF.
   The reason this is a complexity is that although the textual order of the
   content of a TEI transcription (the contents of a tei:body element) is
   generally just the order that the text appears in the file (so-called
   "document order"), this order can be modified; TEI has linking mechanisms
   (such as @next and @previous attributes) which can link parts of the text
   together in alternate orders, and logically join together segments of text
   that appear out of order. And there's also a "documentary" mode of analysis
   and transcription in TEI, in which the <facsimile> element contains the
   textual transcription. In this mode, there's no separate transcription in a
   <body> element; it is all embedded directly in the <facsimile>, <zone>,
   etc. markup; privileging the material aspect of the text over the logical

I hope that's helpful!

Might I ask, by the way, what use case you have in mind, particularly? Were
you interested in making TEI texts that refer to IIIF services, or perhaps
in making IIIF services which publish TEI texts? Or something else?

Personally I think the two models are conceptually very close and I can see
possibilities for translation in both directions.



On 6 July 2017 at 20:58, Ben Brumfield <[log in to unmask]> wrote:

> I'm more familiar with a IIIF canvas than a TEI surface, but the TEI
> guidelines suggest that they match.  But let's explore a use case I
> understand from IIIF and ask how TEI treats it to make sure, though:
> A particular leaf--pretend it's a letter written by Abraham Lincoln--has
> been separated into fragments by an autograph dealer, and that those
> fragments have been imaged separately from each other.  In IIIF, we'd
> create a single canvas to represent one page of the letter, then use one
> image annotation for the text fragment and another image annotation for the
> signature fragment.  Both images would annotate the canvas, which is itself
> a somewhat hypothetical representation of the original page.  Transcripts
> would be textual annotations on the canvas as well, rather than using
> either image as a target.  (The verso page could have its own canvas with
> image annotations as well.)
> Does surface work the same way?
> Ben

Conal Tuohy