Everybody's always seeing those pictures with the backgrounds showing through, such as the examples above, but no one seems to be able to make them. Well this little program should help out a bit.
Transparency only works with GIFs, as far as I know. The GIF format supports up to 256 colors, from 0 to 255, and allows you to specify one of those colors as transparent. To do this, you'll probably need a program like GifTool, for MS-DOS.
Here's a quick tutorial. Open up a .GIF in your paint program, and find out the background color's RGB values. Black is 0,0,0 and red is 255,0,0. The above .GIF's background is white (255,255,255), whatever. Go to DOS and make sure the GifTool.exe and the .GIF file are in the same directory.
Type: giftool -B -rgb ###,###,### NAME.GIF.
Where ###,###,### are the RGB values of your background color and NAME is the name of your .GIF file.
Viola! You've got yourself a transparent .GIF ready to be used in any way you wish.
You may want to try giftool -help for other options.
Anyway, Click here to download GifTool.ZIP. (69k)