Bryce L Nordgren a écrit :
I would suggest, for the purposes of portably accessing CRS stored in image
files, that we do exactly as Martin suggested but use "Recommended XML/GML
3.1.1 encoding of common CRS definitions" (OGC's 05-027r1). It's
specifically limited to "how to use GML 3.1.1 to encode CRS relevant to
image transport." In other words, it's exactly what we want, portable
across file formats, and does not include a bunch of half-complete notions
of things that might be nice.
I'm confortable with that (I have to admit that I just had a quick look on those specifications). Note that we also need to encode the coverage Envelope. We may take the relevant part from GML if needed.
I suspect that the most tedious task may be to implements a XML parser/formatter for CRS. However, I'm not sure if this task is unavoidable since IIOMetadataFormat can work with arbitrary Object (not just String).
Note that since Martin is talking about implementing an IIOMetadataFormat,
we're really not discussing how the information is _stored_, but rather how
it is _communicated_ from the ImageIO plugin to Geotools. For all we know,
the XML is just a beefed up world file accompanying any image...or extra
tags in a TIFF file...etc.
Exactly. Thanks for the clarification.
Martin