A recorder’s “disk” will look empty on a computer because all video has been recorded to the disk using an unpublished file format instead of actual files. We then image the disk, identify each video stream based on their structure, isolate the channels (video streams), and export the desired time window as something you can watch (as opposed to just being a picture); however, the recorder continues to overwrite the existing footage as it runs. So, time becomes a significant factor here.
DVRs (digital video recorders) and NVR (network video recording) units are both designed with a continuous loop, therefore once the disk reaches capacity, the unit begins rewriting the oldest recordings. Each hour that a unit remains active equates to one less hour of older footage available. To avoid losing old footage, shut down the unit and extract the disk prior to doing anything else.
DVR disks are standard hard drives; yet almost everything else about them is non-standard, which is exactly why when you plug the DVR disk into your PC, the volume appears blank or unformatted.
Surveillance hard drive units operate continuously for extended periods (typically 24/7) in a warm cabinet environment (which is far more demanding than a typical consumer computer hard drive).
Surveillance drives continuously write and typically have the lowest cost of all components. Eventually, bad sectors will accumulate to the point that recording can’t occur anymore or the device won’t boot.
Failure of the power supply, circuit board, or firmware within the device itself. Typically, the hard drive remains intact and so does your evidence, but as with most things, the obstacle isn’t damage; it’s simply a matter of a non-standard file format.
A PC came into contact with the drive, and Windows asked if you wanted to format the drive. You said yes. Recoverable, though it’s going to be much tougher, and time is not on our side.
Simply put, once an event has passed beyond its retention period, then there is nothing that can be done to retrieve the evidence that has now been overwritten.
Factory reset or channel wipe. Often still recoverable, since these tend to only remove indexing from the video data, not the actual data.
This project is not about creating an operational audio/video recorder; we want to create a video (or even multiple videos) that can be watched and potentially passed on to someone else.
The disk is first imaged as read-only, using short passes when the program encounters “bad” sectors; those bad sector locations are then skipped where the program will never get them. After that process, from this read-only image, the video streaming components are located via structural analysis as opposed to a file list of names; they are then grouped together by channel number and sorted into time-stamp order. If the proprietary container used on the original video recording prevents playback on typical computers, individual frames of the video are extracted and placed into a standard playable format such as MP4 or AVI. Therefore, the recorded footage can play on any computer without requiring installation of the manufacturer’s proprietary player software.
Please let us know what specific window you’re looking for early on. The recording disks we receive are quite large with most of each disk containing no relevant information, therefore knowing the date/time frame and camera will help expedite the process and produce a better product.
It’s priced based on the flat rate for the type of work being done regardless of which recorder it was done on.
We charge £300 +VAT to recover data from CCTV, DVR and NVR systems; this price is confirmed after a free 48 hour diagnostic. We require a 50% deposit upfront when doing any of these jobs and we charge the same amount whether or not your required footage made it through the overwrite loop, because reverse engineering an unknown recorder format is the same amount of effort regardless of whether or not the footage existed to begin with.
When possible please send us just the hard drive from the recorder (instead of the entire unit) along with identifying the make and model of the recorder, approximately when/what time frame you are looking for in addition to which camera(s). For detailed descriptions see: CCTV Recovery: A SkyHawk That Warned First.
Before we can start work on your unit you will need to send it in for a free diagnostic review and tell us briefly what happened. We then have one of our engineers review your unit & verify your exact quote in writing prior to starting any work.
Before dropping off or posting your device please request a quotation either by telephone or using our quotation form. The first step to recover your data is to get the device to us. Please ensure that you pack the device securely, include your contact information and then forward it to us. Once we have completed the free diagnostic of your device we will provide you with your exact price in writing prior to commencing any further work.
Posting it? We would suggest using a tracked and insured delivery method. Want to drop it off? That’s okay too. Monday to Friday, from 9am to 5:30pm is good; no appointment necessary: simply prepare the item as described above.
If you want a few more details first, fill out this form and let an engineer go through it and send you back a custom quote.
We’ll be in touch shortly. If it’s urgent, call 01865 593000.
This is a list of some of the most common questions that customers ask us before shipping their recorder/card in.
Generally. DVR/NVR units record to standard hard drives, however they use their own proprietary (and undocumented) format to do so. Therefore the drive is ‘imaged’ in read only mode and the video recorded from the device is pulled based upon structural attributes, rather than pulling each file individually. In most cases where the recorder itself has failed, the data contained on the drive (the video) remains intact.
Typically, recording devices loop constantly. As a result, older footage is continually being over-written once the disk reaches capacity, often within days or a few weeks (depending upon the number of cameras, resolution and frame rate). It is imperative, if the footage is important, to remove the disk from service immediately; with each hour that continues to be recorded, there will be additional loss of available footage.
No. Windows does not support the proprietary format used by these types of devices and therefore simply assumes that the disk is blank, which is why we see so many recorder disks arrive already initialised. Simply decline the prompt and unplug the disk from the computer.
Yes, and if we know in advance which video footage you need then that is very helpful, as a timestamp is embedded into the video’s format rather than being stored within a file’s metadata, therefore allowing an exact time to be extracted from a larger video rather than exporting every frame.
A format that does not need the software created by the recorder’s maker: this is to remove the data (frames) from the company container and put them in a common format such as MP4 or AVI which then can play on any computer and will allow you to share your video footage with an insurance company or the police.
We charge a flat fee of £300 + VAT for the service, confirmed after a free 48-hour diagnostic, regardless of whether we recover your footage or not. The cost of the service includes a 50% down payment upfront, because we spend the same amount of time and money doing our job; i.e. regardless of if the data survives the “overwrite loop” or if it doesn’t.
We will do a free assessment of the issue with the footage (which we recover by camera and time from a DVR, NVR, or SD card, even a failed recorder) and export it into standard file format so that it can be given to your insurance company or the police. Contact us.