gzipped images in SIAP 1.0

[Steve Allen]

On Tue 2007-05-22T11:06:06 -0700, Rob Seaman hath writ:
> A tile compressed file is a legal FITS bintable.

Unfortunately in the purely FITS world "legal" has no mechanism for
proceeding to "comprehensible".

> Tile compression is superior in many regards and will likely gain
> market share rapidly once a certain critical mass is reached.

A nice feature of the HTTP is that there is a protocol
(Accept-Encoding) by which any client can specify whether it groks
content-coding of gzip.  FITS is not a real-time-negotiated protocol,
so it can't address the mechanism by which a client could specify
which of the IAUFWG-registered conventions it can handle.  The best
that FITS can do is to register the conventions such that SIAP and
other VO protocols can specify them by name.

--
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