The image was extracted using the graphics select tool of Acrobat Reader, pasted into Graphics Converter, cropped, verified to employ at most 256 shades of gray, and saved as a PNG image file. The PNG was opened in The Gimp and saved as a greyscale JPEG image file at 75 percent quality on The Gimp's scale. An alternate image found on the Defensible Space website was found to use four colors.