image - How to get better transparency with GIFs?

Question

Is there any software, plugin or technique that would allow creating/exporting PNG-like GIFs with smooth transparent edges, at least for smaller images like bullets or buttons.

I really have to use GIFs sometimes for IE6 so it'd would be great to know if such a tool exists?

Thanks

Answer 1

No, the GIF format does not support alpha-channel transparency like PNG does. You can only select one out of the 256 possible colors in a GIF to be transparent.

If you know roughly what color the background will be, the best you can do is create the GIF with the same background you plan to use it on, then select the background color as transparent. The smooth edges will look smooth against that specific background, but horrible against other colors.