What are annotations?

We have seen many examples of annotations during the course and they have many uses including:

Transcribing documents
Commenting or analysis of content
Highlighting areas of the item like hand written annotations on a printed book
Teaching or explaining content (Storiiies and Exhibit)

and we also saw yesterday that annotations are fundamental to how a IIIF Manifests work with images and video painted on to a canvas with annotations.

Annotations in IIIF follow the W3C annotation model and its precursor Open Annotations. I will go through the differences briefly later but the model is conceptionally similar:

The annotation is made up of two parts. The body which is the resource you want to annotate on to something and the target which is the thing you are annotating. Examples of bodies might be:

Text transcription of a line
Video giving background to a painting
IIIF Image painted on to a canvas

A target might be:

A whole canvas
A part of a canvas (maybe a line in the transcription example above)

Example Annotation

A simple commenting annotation looks like the following:

{
    "@id": "http://localhost:8887/coin/list/1",
    "@type": "oa:Annotation",
    "motivation": "commenting",
    "resource": {
        "@type": "cnt:ContentAsText",
        "format": "text/plain",
        "chars": "Zeus seated on stool-throne"
    },
    "on": "http://localhost:8887/coin/canvas#xywh=3706,208,522,522"
}

This is using Open annotations and the keys map as follows:

Body -> resource
Target -> on

Other things to take note of are:

motivation is commenting
Annotations should have an @id

In this example the body or resource is the text Zeus seated on stool-throne. The canvas id in this example is http://localhost:8887/coin/canvas and the #xywh=3706,208,522,522 denotes we are looking at a rectangle starting 3706 pixels from the left, 208 pixels from the top and with dimensions 522 pixels wide and 522 pixels high. The image mentioned in this annotation is:

Caveat: Open Annotations vs Web Annotations

For this workshop we will be focusing on Open Annotations which are in the examples above. One of the changes with IIIF version 3.0 is that we are moving to the W3C Web Annotations model. The concepts are the same but the JSON is slightly different. The transcription example now looks like:

{
    "id": "http://localhost:8887/coin/list/1",
    "type": "Annotation",
    "motivation": "commenting",
    "body": {
        "type": "TextualBody",
        "format": "text/plain",
        "chars": "Zeus seated on stool-throne"
    },
    "target": "http://localhost:8887/coin/canvas#xywh=3706,208,522,522"
}

The changes are:

@id becomes id
@type becomes type and oa:Annotation becomes Annotation
resource becomes body
on becomes target
The body type changes from cnt:ContentAsText to TextualBody.

Quite a few changes but it is defiantly clearer to understand.