dereferenceable id as region in iiif-image uri

[damooo]

Namaste all. Thanks for your work. Consider only if it is tenable and sensible.

Subject

This is request for supporting dereferenceable id as value for region url part, as uri:<URI> syntax.

Description

If there is a specific resource at an uri, whose region is specified in selector property as a oa:FragmentSelector, or oa:Choice, then It will be great if we can refer to it in region property like follows:

https://example.org/<id>/uri:<specific-res-uri>/full/0/default.jpg

where <specific-res-uri> is an URL-encoded URI, which will be dereferenced to x,y,w,h syntax. <specific-res-uri> can be absolute/relative/compact uri. Dereferencing mechanism can be implementation specific.

Why?

When we have a resource ( specific resource or annotation of/on other resource) at an uri, Presently if we want to see it's image representation on client-side, First we have to first dereference that uri in first request, and compute region str, and then can create image element. If we want to display multiple of such representations, we have to fire two request for each, and have to co-ordinate async flow. Insted, if we can reference region val by specific-res's uri, Then it will be trivial flow, and can be done without many idiosyncracies.

[azaroth42]

To make certain that I understand...

• You have Web Annotation SpecificResource instances that are available at some URI. Those Specific Resources have a FragmentSelector, which will then have a value such as xywh=0,0,100,100. Presumably also a source to an image.
• The idea is to then refer to the specific resource instance by its URI to act as a reference to the value (0,0,100,100) rather than including the x,y,w,h in the URI of the image request. The server would then dereference the URI that was embedded in the region slot, parse the response, extract the FragmentSelector and apply its value as the requested region in the Image API.

Is that right?

[damooo]

Yes.

And much better is, the specific-resource id to be used in replacement for both id and region together if possible. Because, SpecificResource (in this case) by definition contains information of both source full resource id, and selector with x,y,w,h. But then we have to properly design uri syntax with out ambiguity.