Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!tut.cis.ohio-state.edu!ucbvax!ucdavis!iris!foss
From: foss@iris.ucdavis.edu (Jim Alves-Foss)
Newsgroups: comp.graphics
Subject: Re: GIF viewers are inconsistent
Message-ID: <4705@ucdavis.ucdavis.edu>
Date: 20 Jun 89 20:40:30 GMT
References: <5300015@ux1.cso.uiuc.edu> <1305@cbnewsc.ATT.COM>
Sender: uucp@ucdavis.ucdavis.edu
Reply-To: foss@iris.ucdavis.edu (Jim Alves-Foss)
Organization: U.C. Davis - Department of Electrical Engineering and Computer Science
Lines: 22

In article <1305@cbnewsc.ATT.COM> vgopal@cbnewsc.ATT.COM (venu.p.gopal) writes:
>In article <5300015@ux1.cso.uiuc.edu> phil@ux1.cso.uiuc.edu writes:
>
>>...  Can someone explain why different programs show the same
>>GIF file in different colors?  Is something defective in the file?
> ...
>select 256 colors out of 262 thousand colors.  You will find that when
>you use these modes, the differences between the display programs
                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>disappear.  The differences mainly exist because the GIF colors
 ^^^^^^^^^
>specifications have to be approximated by what the display card can
>show and different programs have different methods.

Different display programs also have different default modes. FASTGIF
displays GIF files in EGA modes but does a good approximation of better modes
using a dithering technique, VGIF uses the VGA modes and I'm unsure
about the others. Check the documentation that comes with these programs to
see what modes they support and then use the one best suited for YOUR 
particular hardware configuration (ie FASTGIF for EGA, VGIF for VGA, ...)

-Jim Alves-Foss (foss@iris.ucdavis.edu) /* of course these are MY opinions */