Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!zaphod.mps.ohio-state.edu!uakari.primate.wisc.edu!crdgw1!sixhub!davidsen
From: davidsen@sixhub.UUCP (Wm E. Davidsen Jr)
Newsgroups: comp.graphics
Subject: Re: Alchemy on PC (JPEG compression): some findings
Message-ID: <2999@sixhub.UUCP>
Date: 29 Jan 91 02:24:35 GMT
References: <1115@accucx.cc.ruu.nl>
Reply-To: davidsen@sixhub.UUCP (bill davidsen)
Organization: *IX Public Access UNIX, Schenectady NY
Lines: 27

In article <1115@accucx.cc.ruu.nl> jaapv@accucx.cc.ruu.nl (Jaap Verhage) writes:
| 
| Recently, the program Alchemy was posted to alt.sex.pictures. As I was rather
| impressed by the included file SAMPLE.JPG, I decided to try out the program
| on some GIF files.
| I chose two: one from alt.sex.pictures, KATYA3.GIF, showing a naked
| masturbating girl with lots of nicely tanned skin-tones (among other things).
| I guess this is a scan of a color photograph. The second file is a raytraced
| picture made by Dkbtrace from a modified version of its sample input file,
| WINDOW.DAT. The output was a Targa file, which was converted to GIF by Piclab
| version 1.82 with dithering off and called WINDOWJV.GIF. The picture contains
| a uniformly blue globe on a brown wooden floor; in the globe, a white
| windowpane is reflected, as well as some of the floor. Both GIF files are
| 640x480 pixels, 256 colors.

  Although I am neither an author or fan of that program, if you have
the original 24 bit Traga file, you might try converting the Targe to
JPEG, then the JPEG to GIF for vieweing. It's my impression that Alchemy
reacts very badly to data in some GIF files, possibly caused by the
dithering, if any. I have seen many cases where it combines a visible
loss of quality with actually making the file (after conversion back to
GIF) larger than the original, as well as fuzzy. The worst of both worlds...
-- 
bill davidsen - davidsen@sixhub.uucp (uunet!crdgw1!sixhub!davidsen)
    sysop *IX BBS and Public Access UNIX
    moderator of comp.binaries.ibm.pc and 80386 mailing list
"Stupidity, like virtue, is its own reward" -me