[fitsbits] Fits recognition

[Steve Allen]

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 <juphoff at tarsier.cv.nrao.edu>
# 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

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