GIMP Transparency

From UC_Chemistry

Creating files with transparent backgrounds using the GIMP (GNU Image Manipulation Program) can be easy and fun. Just open up an image, then follow these steps:

1. Verify that the image has an alpha channel (may not be necessary)
   1. Open the Layers Dialog (Dialogs->Layers)
   2. Right-click the Background Layer
   3. Select Add Alpha Channel if you can (if you can't you don't need it)
2. Select a region to delete (Tools->Selection Tools->By Color Select)
   1. Dialogs->Tool Options will give you some nice intersection/add/remove from currently selected region options if you need them.
3. Cut it out! (Edit->Cut)
4. Save your work (File->Save As)