Author: Phil Froklage

A filesystem is a term that Magnet Forensics uses to refer to a specific family of DVRs. Families are often made up of several different lineages all combined, right? We see DVRs the same way. We deal with the internal computer components, namely mainboards and chipsets, that come inside the DVRs. Many people are surprised … Continued

Many DVR users believe that by deleting video through the DVR interface, they are rendering video unrecoverable. Fortunately for forensic investigators, this is not the case. In most instances, when video is deleted through the DVR interface, only the index (or accessibility) to that video is being deleted. Assuming the video itself has not been overwritten, DVR Examiner may be able to recover it.

Data recovery is a key function of DVR Examiner for all our users, despite varying case load and case nature. An efficient workflow, and the ability for users to customize the workflow they follow based on their particular case needs, ensures rapid time to evidence, and is a major focus as we release new versions of DVR Examiner.

Data recovery with DVR Examiner works by reverse engineering the many different DVR filesystems to locate and extract video footage. Most DVRs use a proprietary filesystem. Sometimes this is in conjunction with a known filesystem, often Ext 2 or 3, but even in these cases the video data is typically located in a large proprietary partition which won’t be recognized by conventional computer forensic tools. However, if you take a closer look at these “unallocated” spaces, you may find some familiar structures and multitudes of highly compressed video data.

Hikvision-based systems store date/time metadata a little differently than other DVR filesystems, and when it comes to adding support for new DVRs into DVR Examiner, or recovering video manually for a laboratory case, understanding date/time information is critical.