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- Newsgroups: comp.lang.postscript
- Path: sparky!uunet!ukma!cs.widener.edu!eff!world!pd
- From: pd@world.std.com (Peter F Davis)
- Subject: Re: How to make a PostScript image transparent? - Help!
- Message-ID: <C1J77r.H9x@world.std.com>
- Organization: The World Public Access UNIX, Brookline, MA
- References: <C1IDnt.7pL@gabriel.keele.ac.uk>
- Date: Wed, 27 Jan 1993 21:19:02 GMT
- Lines: 49
-
- gerry@keele.ac.uk (G.D.Pratt) writes:
-
- >Hi,
- >I'm taking 2 PostScript files, one created from a Sunrasterfile with
- >rastps and the other from pnmtops and cating them together. The first
- >is a very light greyscale image and the second is a monochrome image
- >with a lot of white. I want the first greyscale image to show thru' the
- >white of the second monochrome image but it gets over written.
-
- >The code where the first ends and the second starts is like this:-
-
- >gsave
- >540.0 810.0 scale
- >/s 400 string def
- >400 600 8
- >[400 0 0 -600 0 600]
- >{currentfile s readhexstring pop} image
-
- >image data here...
-
- >797C7E8284898B8D91929496999B9D...........
- >grestore
- >%!PS-Adobe-2.0 EPSF-2.0
- >%%Creator: pnmtops
- >%%Title: noname.ps
- >%%Pages: 1
- >%%BoundingBox: 15 90 597 671
- >%%EndComments
-
- >Prolog here...
-
- >%%EndProlog
- >%%Page: 1 1
- >gsave
- >15.3 90.5706 translate
- >581.4 580.859 scale
- >1074 1073 1
- >[ 1074 0 0 -1073 0 1073 ]
- >{ picstr readstring }
- >image
- >8000f9008000f9008000f9008000f9008000f9008000f9008000f9008000....
-
- >Is there something I can put _before_ the second one starts to make it
- >transparent? Or some alternative approach perhaps with PBMPLUS. Thanks.
-
- Use imagemask instead of image for your second, bitonal image. See the
- PostScript Language Reference Manual for details.
-
- -pd
-