forensic image processing

Digital image forensics is a brand new research field which aims at finding the authenticity of images by recovering information about their history. Two questions about the history and credibility of an image can be raised: was the image acquired by the device it is claimed to be sensed with? Is the image still depicting the captured original scene? The first question is of major interest when the knowledge of which is the source of the image represents the evidence itself, for example, since it allows to know the user or device that made the picture; the second question has more general interest. Answering to those queries is relatively easy when the original image is known. In practical cases, though, almost no information can be assumed to be known a priority about the original image. Investigators need, therefore, to authenticate the image history in a blind way.