[fitsbits] Fits recognition

On Thu 2007-08-16T17:22:29 +0200, eggpap hath writ:
how to know programmatically if a fit/fits extension file is a true fit
file?

The quickest test is the one Jeff Uphoff wrote for the /etc/magic
or /usr/share/magic file which is used by the unix "file" program.

# FITS format. Jeff Uphoff
# FITS is the Flexible Image Transport System, the de facto standard for
# data and image transfer, storage, etc., for the astronomical community.
# (FITS floating point formats are big-endian.)
0 string SIMPLE\ \ = FITS image data
109 string 8 \b, 8-bit, character or unsigned binary integer
108 string 16 \b, 16-bit, two's complement binary integer
107 string \ 32 \b, 32-bit, two's complement binary integer
107 string -32 \b, 32-bit, floating point, single precision
107 string -64 \b, 64-bit, floating point, double precision

This does not prove conformance with the FITS standard, but
it's a good start.

also see verifits and its kin
http://fits.gsfc.nasa.gov/software.html#VERIFITS

--
Steve Allen WGS-84 (GPS)
UCO/Lick Observatory Natural Sciences II, Room 165 Lat +36.99855
University of California Voice: +1 831 459 3046 Lng -122.06015
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