SegmentationMask, BoundingBox

[VladimirAlexiev]

Looking at unusual schema subclasses, I stumbled upon these two:

croissant:SegmentationMask a rdf:class ;
  rdfs:label "SegmentationMask" ;
  rdfs:comment "A data type representing a segmentation mask." ;
  rdfs:subClassOf schema:StructuredValue .

A segmentation mask is an array of pixels, right? Then schema:StructuredValue, if you look at its properties, is not at all appropriate.
You could use xsd:base64binary for the payload, but should also describe dimensions (width, height, pixel bit size).

croissant:BoundingBox a rdf:class ;
  rdfs:label "Label" ;
  rdfs:comment "A data type representing a bounding box." ;
  rdfs:subClassOf schema:Text .

• Why do you need a subclass (or sub-datatype)?
• The respective schema prop https://schema.org/box is defined as a string, so use xsd:string (see use XSD datatypes not schema.org datatypes #654)
• Another option would be to use some geospatial standard, eg the geosparql:wktLiteral datatype (but I think that's overkill for a simple bounding box)

[pierrot0]

Segmentation mask:
https://github.com/mlcommons/croissant/blob/main/docs/croissant-spec.md#segmentationmask

The idea is to be able to specify the segmentation mask either as a sequence of coordinates (polygon) or has image overlays.

Bounding box:
https://github.com/mlcommons/croissant/blob/main/docs/croissant-spec.md#boundingbox

The idea is to be able to specify the bounding box using different formats, which schema.org/box doesn't allow.

In general, with Croissant, we tried to define a format which can be used to describe datasets packaged with most common formats, without imposing a particularly way of packaging such datasets (either file format, or data format).