[iaufwg] FITS Registry Proposal

[Steve Allen]

On Fri 2006-03-24T15:49:01 +0100, Lucio Chiappetti hath writ:
> I was calling it "small detail" because I was thinking of manual usage of
> the "file" command, something which myself will rarely do. After all the
> typical user has little interest in knowing what conventions an odd FITS
> file he received is following. Either he knows ALREADY because it's part
> of a large dataset for his favourite instrument, or is an occasional
> dataset and he will just inspect it with fv or other favourite tool.
>
> Or otherwise he would use a data organizer to classify the files (e.g.
> http://cosmos.iasf-milano.inaf.it/pandora/drago.html) according to
> specific pipeline needs.
>
> It's not a small detail in the sense it is not a trivial business to set
> up an "universal classifier". So one should be careful to embark in a
> large business if there is the probability it will be under-used.

I heartily support the notion of coining a new IAUFWG-approved,
reserved, string-valued keyword that would give the name of an
officially-registered convention in use by that file.

I am very hearty about this because it would address the issue which
was not faced by the FITS MIME initiative.  The instigation for
running FITS MIME through the FITS and Internet processes was that
Bill Joye was trying to figure out a way that the ds9 image viewer
could tell what it should try to do with a FITS file obtained via a
URL.  In the end it proved infeasible to classify the FITS file
conventions using the MIME media type.  This means that Bill Joye's
problem with FITS files remains unsolved.

Currently the ds9 viewer must be told via external means what sorts of
techniques it should use when viewing a Multi-extension FITS file
conforming to the HST, or NOAO mosaic, or various X-ray, etc.,
conventions.  It would be beyond very cool if by casual inspection of
a FITS file it were possible to tell how it might be displayed.

Creating a new reserved keyword is the sort of thing the FITS
community has done over and over again.  Setting up a registry of
unique names for conventions is the mechanism that Bill is currently
addressing.  Alas it is still not a small detail.

Going the next step farther to machine parsing is yet more work
and mechanism.

--
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