color screen dumps to greyscale

[imager at ccwf.cc.utexas.edu]

>I am trying to dump an RS6000/320 GRASS Display Window to a postscript
>rpinter.
>I use the command:
>
>xwd -bitmap | xpr -device ps | lpr -P<printername>
>
>and this prints the xterm border with a blank interior.
>Presumably, I need some way of converting the colour xwd dump
>to greyscale.
>
>Any ideas much appreciated.
>
>Joe Mintz, Dept Computer Science, Birkbeck College

If you want to get rid of the borders type the following:

"xwd -nobdrs -out <filename>" and then click on the window that you want to
dump to the file.

To convert from a color image to greyscale you could use Jeff Poskanzer's
public domain PBMPLUS toolkit available via anonymous FTP as
ftp.ee.lbl.gov:pbmplus*.tar.Z, 
wuarchive..wustl.edu:graphics/graphics/packages/pbmplus/pbmplus*.tar.Z, and
export.lcs.mit.edu:contrib/pbmplus*.tar.Z.

(I think *=10dec1991). Then convert to pnm format using xwdtopnm and pipe that
to the greyscale converter (I can't remember which one that is but the help
file will tell you).

There are several other graphics conversion packages available such as -the
IM raster toolkit, Utah RLE Toolkit etc. but I haven't used them although I'm
sure that they offer the functionality that you require -direct any
questions to alt.graphics.pixutils or comp.graphics...

You may xv on your system anyway and could use that...

Hope this is of use,

Regards,

Tony Gale,
Research Specialist,
City of Austin, Tx.