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ISO-TC211 / ISO19111

Revision of ISO19111 - Spatial referencing by coordinates.
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Image CRS #41

Open marqh opened 6 years ago

marqh commented 6 years ago

The new ISO19111 draft does not include ImageCRS, this has been removed as have the related ImageDatum and ImageCS.

There is critical metadata for managing images as referenced grids that has been removed from 19111 as a result.

This key metadata used to be attached to an ImageDatum, as pixelinCell, with values from a code list, either cellCenter, or cellCorner

In the new version of 19111 there is no ImageDatum or ImageCRS.

An image is a grid, a coverage, 19111 does not enable the definition of a grid. The coordinate tuples representing the cells of a grid may be georeferenced using 19111, for example using an EngineeringCRS.

A consequence of this is that there is nowhere to store whether pixelInCell = cellCenter or pixelInCell = cellCorner within 19111

The 19111 editing committee request that this metadata is provided within the next version of 19123, enabling an image to be properly described as a 19123 coverage. This would be a change to the normative sections of 19123.

It may also be useful to add an informative annex to 19123 as well, providing examples of how to georeference images, using 19123 and 19111 (and perhaps 19162), as this is a common, widespread use case for coverages.

pebau commented 6 years ago

request accepted for forthcoming ISO 19123-1. I will come back with the draft specification before release to seek feedback from this group. (approx mid-2018)