Locating Videos Using Electromagnetic Interference

Locating Videos Using Electromagnetic Interference

Dr Vince Calloway
Dr Vince Calloway
Director & Co-Founder, Polygeist

Videos of CSEA, Hostage Videos, and Extremist Propaganda represent harrowing examples where defence and security analysts are confronted with the proof of a ‘threat to life’ crime, and have only the video source with which to start their investigation.

The absolute priority is to determine the immediacy of the threat; the time the video was produced and the jurisdiction of any victims. This is an incredibly difficult task when original video metadata have been removed, when hosting platforms have deliberately obfuscated the uploading party, and when filming has been carried out indoors with no visible geolocation markers.

Currently, the only way to determine the time and location of the footage when devoid of metadata is to manually review the content, painstakingly looking for clues in the background: face shots of the victims and perpetrators, logos, voice captures, background noises - anything that provides a link to the location or time at which that video was filmed. This time-consuming specialised process can take many days or weeks of effort. As a result, investigators are rightly proud of breakthroughs made using these methods, but would unquestionably benefit from an immediate indicator of the time and location the video was created.

Furthermore, the problem demands scale as the numbers of these harrowing videos expand at an ever-increasing rate. Processing each video, requiring days and weeks of investigative effort, is not currently feasible when thousands of videos are pouring onto the investigative stack. Whether from streamed or seized media, this workload is enormous and there are insufficient resources available to process all the available material and prioritise those representing the greatest risk.

Polygeist have developed a technology to extract tiny fluctuations in ambient lighting in a video, that pinpoint the exact time and location of the recording. We have proven and demonstrated that the fluctuations on mains-powered lighting are perfectly coupled to ground-truth ENF signatures, giving jurisdiction-level geolocation accuracy and a precise time lock (for example, in the UK vs Japan etc.).

Mission Impact

The core capability of ENF allows investigators to determine precise timing of a video recording. For serious criminal offences such as CSAM and abduction cases this gives clear priority when allocating resources and directing investigators to the time and place of the abuse. It also impacts the prosecution of these cases where precise timing can determine the age of the victims at the time of the abuse.

Precise timings of video evidence also plays a part in solving volume crime, either supporting or deconstructing alibis. These crimes range from sexual assault, burglary, theft and many more, where an SOI may claim that video proves they were elsewhere at the time of the crime.

With 20% of operational videos (tested against large-scale LEA holdings) proven to carry the ENF signature, Polygeist have the technology and expertise to support Digital Forensics practitioners and live investigative operations through a variety of software- or service-based models. Book a briefing with me on the link above to discuss how we can help your mission.