GIMP Tricks: Fake Fill Flash Jul 31, 2008, 20 :00 UTC (0 Talkback[s]) (4428 reads)
"Now, there are a couple of different ways you could accomplish the next part, but here’s what I consider the easiest. Choose the Select by color tool (Select > By Color), and click inside one of the blacked out areas. You should see the marching ants appear all over the image. Now, we’re done with the background copy layer, so you can delete it or simply hide it if you choose."