US boffins develop digital imaging forensics

All digital pictures are overlaid by a noise-like pattern of pixel-to-pixel non-uniformity

Researchers at a US university have developed a process that can accurately link digital images to the camera with which they were taken.

The team from Binghamton University in New York claimed that the system allows the identification of a camera in much the same way that tell-tale scratches are used by forensic examiners to identify the gun from which a bullet was fired.

The process could have several applications, according to the academics, including bringing child pornographers to justice.

"The defence in these kind of cases would often be that the images were not taken by this person's camera, or that the images are not of real children," said Jessica Fridrich, associate professor of electrical and computer engineering at Binghamton University.

"But if it can be shown that the original images were taken by the person's mobile phone or camera, it becomes a much stronger case than just a bunch of digital images that we all know are notoriously easy to manipulate."

Fridrich and two members of her research team, Jan Lukas and Miroslav Goljan, are co-inventors of the technique, which can also be used to detect forged images.

The trio have applied for two patents related to the technique, which provides the most robust strategy for digital image forgery detection to date.