The LEVA (Law & Emergency Services Association) definition of authentication is the process of determining if a digital image, video or sound recording (DME or digital media evidence) is an accurate presentation of that which it purports to be.
Due to a vast number of video editors, image processing, deepfake and diffusion based applications, many of which widely available at no or low cost, it is relatively simple to alter a digital media file so to deliberately change its context and its evidential value.
A forensic imagery expert is equipped with knowledge and tools (such as Amped Authenticate) that will help him/her to determine if an image or video has been altered since its raw acquisition.
The metadata of a digital media file for example (metadata being quite simply data about data - such as date and time, GPS co-ordinates of image location, capturing device etc) can give an expert the first clue of deliberate manipulation or lack of. Other authentication tehcniques include PRNU (Photo Response Non-Uniformity) verification, macroblocks analysis, double encoding detection and shadow analysis.
The details of the analysis are then presented in an exhibited report (with signed witness statement) in line with criminal justice requirements. An illustration only pack is also produced so this can be included in the jury bundle in order to facilitate the presentation of the imagery evidence in court.
Please contact us for a free assesment of the media, scope for analysis and a quote.