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From: rlee@weaver.ads.com (Richard Lee)
Newsgroups: comp.sys.atari.st
Subject: Re: GIF format ?
Message-ID: <RLEE.90Nov21123910@weaver.ads.com>
Date: 21 Nov 90 20:39:10 GMT
References: <2499@gould.doc.ic.ac.uk> <647@fsucs.UUCP>
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Organization: Advanced Decision Systems, Mountain View, CA 94043, +1 (415)
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Lines: 33
In-Reply-To: boyd@fsucs.UUCP's message of 21 Nov 90 02:37:06 GMT

In article <647@fsucs.UUCP> boyd@fsucs.UUCP (Mickey Boyd) writes:

|The program of choice here is Digispec.  I believe Alpha Systems sells it.  It
|will take a .gif file and convert it into a .sps file (spectrum 512).  It will
|then look about as good as it can on the ST (it takes some time to process 
|each picture).  The resulting .sps file is usually MUCH smaller than the 
|original .gif.  There is a PD viewing program available for .sps files which 
|also can compress them into .spc files (I may be backwards about .sps and .spc,
|now that I think about it!).

A few corrections: First, Digispec is from Trio Engineering, the
creators of Spectrum 512, and costs ~$40.  Its primary purpose is for
use with their digitizer; gif conversion is an add-on.  Second, it will
let you save the result as either an _.spu_ or an .spc file, the latter
being the default.  Every Spectrum viewing program I've seen will work
with either of these.  Sps is a more compressed representation,
apparently _not_ developed by Trio; .sps files require spslidex (PD) to
view or convert, I'm told.

Digispec does indeed do a better job, not surprisingly, than the PD
converters Bgif and Gifspec.  The picture quality is better, the files
are smaller, and you can adjust brightness, contrast, color mix, and
dithering scheme as desired.  On the down side, it cuts the top or
bottom (your choice) off of tall gifs, and it screws up the aspect ratio
on the most un-square gifs.

I've seen enough questions on this issue (including my own, a few months
ago) to think there should be something in a periodic FAQ posting on it.
Comments?

--
 RICHARD LEE     rlee@ads.com  or  ...!{sri-spam | ames}!zodiac!rlee
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