Subject: Re: FIT file format

From: [email-masked] (Don Wells)
Date: 09 Dec 1996 18:16:32 GMT

"CS" == Christoph Schittko <[email-masked]> writes:
CS> I am trying to find some information on the FIT file format that is
CS> supported by SGI's ImageVision Library. Does anyone know where to find
CS> some information on the file structure and the different color models ?

'FIT' in the SGI library is probably FITS [Flexible Image Transport
System], the standard data interchange and archival format of the
worldwide astronomy community. See:

The FITS newsgroup:
sci.astro.fits

FITS Basics and Information 
http://ssdoo.gsfc.nasa.gov/astro/fits/basics_info.html

"Definition of FITS" [the FITS standard]
Postscript, 80_pages, 430_KB
ftp://nssdc.gsfc.nasa.gov/pub/fits/fits_standard.ps

A User's Guide for the Flexible Image Transport System (FITS)
Postscript, 100_pages, 574_KB
ftp://nssdc.gsfc.nasa.gov/pub/fits/users_guide.ps

FITS archive at NRAO
http://fits.cv.nrao.edu/

FITS Support Office Home Page
http://ssdoo.gsfc.nasa.gov/astro/fits/fits_home.html

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FITS files are bytestreams which are regarded as being composed of
logical records with length 2880_bytes; i.e. the byte count of a FITS
file should be a multiple of 2880. The first 10 bytes of all FITS
files are 'SIMPLE = ' (i.e., uppercase 7-bit ASCII codes for S, I, M,
P, L, E, two ASCII blanks, ASCII equal and an ASCII blank; this is the
"signature" of FITS). The first logical record of all FITS files is a
header, which is regarded as 36 lines of 80 characters (36*80=2880),
with the lines _not_ delimited by newline codes. Examination of a FITS
file with GNU Emacs and a window width of about 80 characters is
instructive. Simple FITS files (the most common case) transmit
n-dimensional digital images with 8-, 16-, 32- or 64-bits per
pixel. More complicated FITS files can transmit sets of tables and/or
sets of images in addition to or instead of the primary image; the
table and image "extensions" (in FITS-speak) have ASCII headers of
their own in the same style as the primary header.

There is no color model associated with FITS files. 
--
  Donald C. Wells         Associate Scientist         [email-masked]
                    http://fits.cv.nrao.edu/~dwells
  National Radio Astronomy Observatory                +1-804-296-0277
  520 Edgemont Road,   Charlottesville, Virginia       22903-2475 USA

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From: [email-masked] (Don Wells)
Date: 09 Dec 1996 18:16:32 GMT

The FITS newsgroup:
sci.astro.fits

FITS archive at NRAO
http://fits.cv.nrao.edu/

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