PC-Welt, Germany
07-280006
New threat: Computer files hidden in digital images
The emergence of software that enables hiding digital code in photographic
images has given criminals a new way to disguise their activities, but researchers
are working to give law enforcement advanced tools of their own to sniff out such
code.
[New threat: Computer files hidden in digital images]
The emergence of software that enables hiding digital code in photographic
images has given criminals a new way to disguise their activities, but researchers
are working to give law enforcement advanced tools of their own to sniff out such
code.
Researchers at the Midwest Forensics Resource Center at the Department of
Energy's Ames Laboratory and Iowa State University are working on tools for
what's called steganalysis. Steganography
(http://en.wikipedia.org/wiki/Steganography) refers to the concealing of files in
other files, such as JPEG images (the colors of a picture might be slightly
changed to hide data).
"There's lots of room within a digital image to hide data," says Clifford Bergman,
an Iowa State math professor and researcher, in a statement. Bergman and
his fellow researchers are searching for statistical measures to spot hidden data
and are using a pattern recognition system called an artificial neural net to tell
stego images from clean ones. The system in one early test was able to spot 92
percent of the stego images in a sample database.
The Iowa Department of Criminal Investigation is field-testing the program and a
GUI is in the works to make the system easier to use.
The hope, Bergman says, is to come up with strong enough algorithms that
forensic experts can collect evidence that will be admissible in court.