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Re: grey scale [message #12499 is a reply to message #12492]

Thu, 13 August 1998 00:00

Martin Schultz
Messages: 515
Registered: August 1997

Senior Member

Harry Reisig wrote:
>
> We tried loadct, 0 - but it is not publishing quality. Is there another
> grey scale that give sharper images? We are trying to print color images,
> which gives a lot of information that is lost in ct 0.
> Thanks
> Harry
[...]

Maybe you don't want a greyscale colortable after all !! If you want to
print color images in black and white, you may get a more "natural"
image using the colortable that comes with the image (assuming you read
the image with read_tiff, read_gif or the likes). Then you simply have
to produce a *color* postscript file and send it to a b/w printer ;-)

Other than that, you can follow the approach I outlined in my earlier
message and define the colortable yourself. You can create virtually
anything, then convert it to a 0..255 byte array with bytscl and load it
into the color table with tvlct. If you don't like linear grey scale you
can use logarithmic, or you can play around with some arctan function,
etc...

Martin.

------------------------------------------------------------ -------
Dr. Martin Schultz
Department for Earth&Planetary Sciences, Harvard University
109 Pierce Hall, 29 Oxford St., Cambridge, MA-02138, USA

phone: (617)-496-8318
fax : (617)-495-4551

e-mail: mgs@io.harvard.edu
Internet-homepage: http://www-as.harvard.edu/people/staff/mgs/
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[Message index]

		Re: grey scale By: wmc on Fri, 14 August 1998 00:00
		Re: grey scale By: davidf on Thu, 13 August 1998 00:00
		Re: grey scale By: David Foster on Thu, 13 August 1998 00:00
		Re: grey scale By: Martin Schultz on Thu, 13 August 1998 00:00
		Re: grey scale By: Richard G. French on Thu, 13 August 1998 00:00
		Re: grey scale By: Harry Reisig on Thu, 13 August 1998 00:00
		Re: grey scale By: Saeid.Zoonematkermani on Thu, 13 August 1998 00:00
		Re: grey scale By: Martin Schultz on Thu, 13 August 1998 00:00

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