[comp.sys.mac] Is run-length compression possible in PostScript?

marc@rna.UUCP (Marc Johnson) (09/23/88)

I am producing bitmapped images on a LaserWriter Plus using PostScript,
noteably the "image" operator.  The image data can get huge, and I would
like to do run-length compression.  Anybody know how if this is possible
using the "image" operator, or any other method in PostScript?

Please e-mail responses.

Thanx,
Marc Johnson
Rockefeller Univ.

marc%rna@rockefeller.edu (129.85.2.1)
rna!marc@rockvax.bitnet
...cmcl2!rna!marc

gordon@spinifex.eecs.unsw.oz (Gordon Rowell) (09/27/88)

In article <260@rna.UUCP>, marc@rna.UUCP (Marc Johnson) writes:
> I am producing bitmapped images on a LaserWriter Plus using PostScript,
> noteably the "image" operator.  The image data can get huge, and I would
> like to do run-length compression.  Anybody know how if this is possible
> using the "image" operator, or any other method in PostScript?
> 

There are two examples that I know of. Sun2PS, which takes Sun format
windows and generates PostScript images from them, and the X11 version
of xpr. Both use RLL encoding to generate much smaller (e.g. ~30% size)
files. Check with a site near you that has Suns or X11, or they
can be posted if needed. (BTW I have made an X10 version for anyone who
is interested).
		Gordon Rowell	(gordon@spinifex.eecs.unsw.oz)
		Department of Computer Science, 
		University of N.S.W., Sydney, Australia