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Re: FITS tables
Stupendous Man wrote:
>
> > My choice for star list files is FITS tables. One reason is that once
> > we decide on a table format later if we find we need to include one or
> > two more columns we can do this ++without++ breaking older reader programs
> > that don't know about the added columns.
>
> Yup, this is a really good reason. Good enough to justify the
> added hassle of writing out data in FITS table format.
>
> I'll have to find a good, simple library which can write FITS
> ASCII tables. I already use the CFITSIO library ... maybe it does
> the trick? Let me check ... yup, it does. I think that there's
> a Perl module for CFITSIO, too.
Yes I would absolutely recommend CFITSIO. One real neat trick is that
if your program uses CFITSIO then your program inherits the ability to
read FITS files like
ftp://some.guys.pc.org/xxx.data.image.fits[32:1800,24:1850]
In other words you can read a subraster from an file on a computer over the
Internet. There is also syntax for reading out horizontal and/or
vertical subsets of FITS tables, reading and writing data compressed
with gzip or "Rice" compressing and so on. CFITSIO is almost bordering
on "bloat ware" Oh yes I think it can read/write IRAF format files
directly too (but then IRAF can now read FITS, so big deal.) CFITSIO works
on both UNIX, and PC-Windows.
My MK IV driver will use CFITSIO but I've also given it the ability
to output images in JPEG, GIF, TIFF and related formats as well.
Reason being someone my want to put MK IV images up on a web site
in real-time. I also built in an interface to ximtool/SAOimage so
you can see the images as they come off the camera and do simple
interactive plots. Sounds like a lot of work but there are good
libraries for doing all the above.
--
Chris Albertson home: chris@albertson-home.net
Redondo Beach, California work: calbertson@primeadvantage.com