Abstract: Media Forensics is a discipline within the digital and multimedia evidence (DME) field of forensics. DME includes digital evidence such as computers and mobile phones as well as recorded evidence in the form of digital audio, video, or still images. This confluence comes as a result of the ubiquity of digital technology and the commonality of media used to store digital data. For example, an external hard drive that is collected at a crime scene may contain audio recordings and images relevant to a case while the digital video recorder-based security system in the next room recorded audio and video to a hard disk drive during the events being investigated. Or, a cell phone found on a suspect may have been used to record voice notes, videos and still images all related to a case under investigation. Because these items of evidence coexist in a digital realm that is not tangible as most other forensic Sciences are known to be, the necessities of handling digital evidence must be respected throughout the DME discipline. This paper presents a general framework for media forensics analysis and neutral methodologies to interpret and present the results using multiple robust analysis techniques.


Bio: As Director of the National Center for Media Forensics, Grigoras has the privilege to coordinate the Center.s activity, including education and scientific projects. His research encompasses digital signal processing in forensic multimedia, including digital recording authentication, audio/image analysis, enhancement, and automatic speaker recognition. His research into digital signal processing has resulted in advanced methods to authenticate digital audio/video recordings and semiautomatic systems for forensic speaker recognition. Grigoras was chairman of the European Network of Forensic Science Institutes - Forensic Speech and Audio Analysis Working Group between 2007-2009. He is a member of the Audio Engineering Society Subcommittee on Forensic Audio and the International Association of Forensic Phonetics and Acoustics. He has published numerous forensic audio/video articles and is a co-author of Best Practice Guidelines for ENF Analysis in Forensic Authentication of Digital Evidence (2009).

Dr. Grigoras is also co-author of the Encyclopedia of Forensic Science 2nd Ed., Academic Press, chapters on "Audio Enhancement and Authentication" and "Digital Imaging Enhancement and Authentication" (2013).