[alt.graphics.pixutils] Time to upgrade the GIF standard ?

otto@tukki.jyu.fi (Otto J. Makela) (07/27/90)

I'd like to start a discussion on upgrading the GIF standard, on the hope
that someone from the CompuServe development team is listening...

Things I'd like to see on the hypothetical GIF91a standard:
* better compression - some asymmetric 2D compressions squeeze the picture
  real nice and are reasonably fast when decompressing; compression takes
  more time, of course
* pixel shape information - on the PC with a VGA you can get about five
  different pixel ratios, and on just any machine with different graphics
  modes you end up with different shaped pixels in different modes; the
  current standard does not support any pixel information
* more colors per image - now that VGAs are common, we've hit the end of the
  standard; also for example the Amiga is able to show 4096 colors (albeit
  restrictedly)
* define better color coding - for some reason, GIFs made on a Macintosh
  tend to come out a lot darker on a PC (this could be a problem with the
  Mac software, but I suspect that it's something more esoteric like the
  color characteristics of a Mac display/display card vs. a PC VGA)

These are the main points that come to mind.  Comments, anyone ?
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marmoset@ub.cc.umich.edu (Dave Walker) (07/28/90)

In article <OTTO.90Jul27095755@tukki.jyu.fi> otto@tukki.jyu.fi (Otto J. 
Makela) writes:
> * define better color coding - for some reason, GIFs made on a Macintosh
>   tend to come out a lot darker on a PC (this could be a problem with the
>   Mac software, but I suspect that it's something more esoteric like the
>   color characteristics of a Mac display/display card vs. a PC VGA)

Actually this problem is caused more so by differences in monitors. The 
Sony Trinitron monitors which dominate the Mac market are far brighter than 
most VGA and SuperVGA monitors, hence the differences in the images.  
Differences between monitors (and printed colors too) are the sort of 
things that make color desktop publishing so difficult.  There are a 
number of different solutions that have been postulated to get around 
these color incompatibilities, but nothing really simple and convenient 
has popped up yet.  It's pretty hard to globally correct colors when two 
different monitors from the same manufacturer (sometimes even the same
model), for instance, may have wildly different color ranges.

I think the next GIF standard should, at bare minimum, support 24-bitplane 
images, pixel-size information, and possible support for other color 
models (HSB, CMYK). 

 Another enhancement I'd like to see would be an option to include a 
"thumbnail" image, i.e. a miniature representation of the image in the 
file (maybe 64X64 or something) which could be used for quickly previewing 
a bunch of images, or for maintaining a pictorial database of your GIF 
images.

> These are the main points that come to mind.  Comments, anyone ?

+------------------------------------------------------------------------+
| Dave Walker, Marmoset Design Ltd.                                      |
| marmoset@ub.cc.umich.edu                 "I don't read, I just guess"  |
| marmoset@mondo.engin.umich.edu       -Happy Mondays, "Wrote For Luck"  |
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