Closed Circuit Television Video Forensic Identification
Closed Circuit television systems (CCTV) are a very useful tool for businesses, governments, institutions, etc. … mainly because they can keep an area secure and safe automatically without human interaction. Some organizations chose to have security personnel monitor the camera surveillance at a location point within the building while others let the closed circuit television system operate on its own while recording what the camera sees. The general rule of thumb for hard drive storage on these CCTV systems is first in, first out. Which means, after a 30 day period, for example, the video footage that was recorded 30 days ago is erased as the new footage from today is being recorded. Technological advancements have contributed this automatic process to the video surveillance method system.
As a video forensic expert, I am being asked more and more to determine if the accused is in fact present in the surveillance video. Previously this has been a little bit outside of my area of expertise, but it is becoming more and more a part of my video forensic practice. I have recently worked on two cases outside of the United States where the source video footage was a CCTV system. One of the sources did portray the person in question plain as day: there was no doubt that the suspect or the person accused was in this video. This very same system on another separate day recorded another piece of video footage. In this video footage, this accused individual claims that there is an entirely different person present. In this particular video it’s not necessarily as plain as day whether or not the suspect is actually in that video.
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Source: Video Forensic Expert