And GIF is usually only for 256 colors or less, making JPEG's a much better format for pics.

If you really want to get into uncompressed pics, you're looking at bitmaps (BMP) files. My photographer friend has a camera that encodes both in raw and jpeg pics so she can pick the format depending on the needs. Having both on the camera at the same time also saves her time in converting to jpeg and compressing them later.

It wouldn't surprise me if the NoS had something similar given TSA's obsession with having as much detail as possible to determine if something's safe (can't be too careful ya know ). A raw image for the screener to see very clearly with a jpeg that's "good enough" if one had to be saved (for "training purposes" of course).