[fitsbits] FITS and image display

Tim Pearson tjp@astro.caltech.edu
Thu, 11 Apr 2002 10:51:10 -0700 (PDT)


On Thu, 11 Apr 2002, William Pence wrote:

> FITS is not primarily an image display format, so unlike .jpg or .gif
> formats, FITS images generally contain no display scaling information.  With
> programs like DS9, the user can interactively examine the FITS image with a
> variety of image scaling options, but this scaling preference is not saved
> in the FITS file itself.  Instead of converting the FITS image to log scale
> you could instead change the preferences in the image display program to use
> a log display scale by default.

Yes; but there are many applications in which one would like to
associate the preferred display information with the particular image
file.  Has anyone defined an extension for this? e.g., a FITS table
extension with 4 columns: pixel value, display R intensity, G
intensity, B intensity.  The color to be assigned to each pixel would
be derived by interpolation in this table.  Of course one would not be
limited to a single extension of this type.

Tim Pearson
Astronomy Dept 105-24, Caltech, Pasadena, California 91125, USA
Internet:    tjp@astro.caltech.edu