On Sat, 31 Dec 1994 09:04:39 -0500 Michael Friendly <friendly@hotspur.psych.yorku.ca> wrote in next-icon@gun.com:

The source of the problem was an alpha channel in the original image, which  
is not handled by the gif conversion in OmniImage.

I was able to get a reasonable gif image by (a) loading into IconBuilder,  
unclicking alpha in the inspector panel, save; (b) converting with OmniImage  
as before.

It may be nice to convert the alpha channel into a transparent gif color entry.  Because if you just keep a white background it may look nice with OmniWeb's default background (which is white), but ugly with Mosaic's or Netscape's.  You could use the following perl script to do this:

¬  transgif.pl

If you want to know more about transparent gifs, read the Inline Images FAQ:

¬  InlineImagesFAQ.txt

In summary you would have to do the following 3 steps to produce icons for your WWW pages with maximum compatibility:
1. Convert a-tiff to non-a-tiff with just 1 color depth (e.g. 12 bit color) using IconBuilder
2. Convert tiff to gif using e.g. OmniImage
3. Convert gif to transparent gif using e.g. transgif.pl or other tools mentioned in the FAQ

Other methods include:
a) Wait until all other browser (or at least NetScape) support inline tiff
b) Convince the rest of the world that white is the proper background color ¬

- Willi