August 14, 2011: Many years after moving from Comcast to Verizon, and thus losing a big chunk of
free webspace, I've finally moved the pictures in this article to Picasa, so that you can see them again.
Also note that if you know the exact color of the background, you can do the conversion from the command line.
One of the nice things about old-style GIF images is that it was easy to set the background to be transparent, so that it would show up on a web page without a funky border. New-style PNG images can also do this, but there doesn't seem to be a reliable stand-alone way to do this. Fortunately, I found directions for making a transparent background using the GIMP. The directions seem to be for an older version of the GIMP (I'm using 2.2.7), so let me write down the current directions here. They should work on a Windows machine as well as under Linux.
- Bring up the GIMP, and load in your picture. For our purposes we'll use this bit of modern art:
- Now right-click on the image and select Layer > Transparency > Add Alpha Channel. (Alpha Channel is what gets made transparent.)
- Right-click again, Select > By Color.
- Left-click the image on the color you want to make transparent.
- Right-click once more, Edit > Clear. The color you selected should now be replaced with a checkerboard pattern.
- Save the picture, which should now appear like this:
- I'm told that Internet Explorer doesn't do transparent PNGs well, so for youse guys, try a GIF version:
And that's all I know about it.