Accessing data on DVR HDD (AVTECH/CPCAM)

[mfoolb 0]

Hi,

 

I need to extract video files from a hard disk that was used in a DVR; I'm trying to access the data from different OSs but it seems some kind of tricky filesystem has been used.

 

I am not able to identify the exact model of the DVR, it has no CDR or ethernet port just 4 ch audio and video input plus an exteranl 15pin I/O port; I can see the following text printed in the motherboard: AV TECH CORPORATION and 773-M ver1.0 2005/07/22.

Tha case has a tag with CE (European) certification of the product that states: CPCAM573.

 

Can anyone help me in identifying the model of the DVR and point to some technical links? Is there any documentation about accessing this data from PC?

 

Any help is very appreciated, thanks in advance.

 

--

Marco.

[scorpion 0]

Hello!

 

There is no documentation for this DVR.

 

 

 

 

 

 

 

 

 

Hold on!

 

My wife is whispering in my ear!

 

OH!

 

It appears that there is documentation for this DVR!

 

Oh!

 

It appears to be on my website! Who knew?

 

Scroll down till you see a picture of it about halfway down the page.

http://scorpiontheater.com/cpcamtechsupport.aspx

 

Manual:

http://scorpiontheater.com/Documents/AVTech_Manual_English_AVC773M_Motion_V1.0.pdf

 

some blurry pics of an OEM under another model number:

http://scorpiontheater.com/4004.aspx

 

Hardware Reset:

http://scorpiontheater.com/reset.aspx

 

Troubleshooting homepage:

http://scorpiontheater.com/troubleshooting.aspx.

 

If you want the video you will have to put it back in to the DVR. You will need to get a VCR, or a DVD burner and connect it to the video monitor out.

 

The DVR uses a proprietary software to scrunch it down to get it to fit the info on to small hard drives. All you are going to get connected to the PC is a bunch of 1's and 0's. You will need an emulator program to see video and none exist.

[rory 0]

Scorpion any idea of the OS they use?

Im sure they would be using a free real time or embedded OS ... maybe even some form of linux .. either way there are alot of them out there and if one knew the exact one, could perhaps load the ISO in virtual box and connect to that hard drive. I can try it using the HDD from my AvTech, but not until middle of next week when I can afford to have the DVR down for some time.

[scorpion 0]

It is some form of linux.

 

I would love to create an emulator. We may not be able to make it public without getting sued, but it would help law enforcement with dead DVRs and a case going to trial!

[mfoolb 0]

First of all, Scorpion and Rory thanks a lot for your answers; I'm exactly in the situation Scorpion describe: dead DVR.

 

I tried to receive information from CPCAM/AVTECH but without success.

 

With some many AVTECH DVRs out there is it really possible the noone has ever find a 'solution'?

 

Anyway If I manage to find/buy a DVR like the one dead (773-M model I guess) will it work just putting the old disk on the new DVR?

 

Can you suggest a place online where I can try to find one new or used?

 

Last question, if everything I asked for is possible, after mounting the hard disk in the worknig DVR will it start automatically overwriting data also if there will be no video/audio input? To review/save the video registration I will just need to hit the play button and start recording from a DVD burner connected to the DVR via tha main output?

 

Thanks a lot in advance.

 

Marco.

[scorpion 0]

I would make a copy of the hard drive then put the clone in to the exact original model, and then line up the video then start the record button on the DVD burner / VCR.

 

If the DVR does something to the hard drive then you still have the original hard drive to work with.

[mfoolb 0]

Hi,

 

I'm already working with a clone of the original disk (dd-ed the original one, but it seems someone had first put it on a windows machine and I've read that this should have changed some kind of signature on the disk and this will also lose all the index to the file when I'll put the cloned one on a DVR, any information about that?).

 

I've looked at the link you gave in the original response and downloaded the manuals but they don't seem to refer to the exact DVR (dead) model I'm in possess. This one has no network port and the video channel port are distributed in a different way. Do you have any othere reference to point me to (that's way I originally asked)?

 

Searching into the forum I found some other guys with problems similar to mine and I've found at least two data recovery company that declare capability to recover data from AVTECH written hard disk.. with so much interest around this topic I found strange that nobody has published some kind of information about AVTECH approach to filesystem management. Anyone knows old employers of AVTECH or some filesystem guy that has done some deep research?

 

I'd like to receive answers to the other questions in my precedent post if anyone has those (ES: I need to buy a working model of the DVR to continue my try).

 

Do you have any other (maybe more data performance oriented) forum to suggest?

 

Thanks a lot.

 

--

Marco.

[scorpion 0]

Basically it boils down to money. Who is going to pay some software engineer to put it together?

 

The chipsets in the DVR are different then a PC. Putting the firmware in to a pc will not work, and will crash the pc.

 

I wish I could find old FAE AVTech engineers and pick their brain!

 

What is wrong with the manual? Yes, there are various different models with and without networking, and different audio options.

 

What does the different video channel ports mean? Do you mean loop in and loop out?

 

The manual would at least show you how to use the menu, and what the options would mean.

 

Have you tried the manual to the AVC 772?

 

http://scorpiontheater.tech.officelive.com/Documents/AVTech_Manual_English_AVC772_V1.0_DVR4005.pdf

[rory 0]

Windows should not touch the file system, unless the user manually did something to it or has some other 3rd party automated drive software. It just wouldnt come up as a valid drive, at least it would be seen in disk management but perhaps an unknown file system format.

 

AvTech DVRs are mostly purchased by budget clients so in they would not normaly want to spend the money for the labour involved to do a whole lot with it.

[mfoolb 0]

Hi,

 

@scorpion: thanks, the 772 manual describe a much similar DVR. I've also read an interesting thing: it seems that if the cabinet lock is not locked the DVR will not detect the HD and in my case the cabinet lock has been forced to extract the HDD by the police (so it could be possible there's nothing wrong with DVR?!)

 

Does anyone know if I can simulate the locking of the cabinet? (I noticed there are only two electric cables connected to a jumper on the motherboard)

 

@rory: I was referring to what I read on this thread: https://www.cctvforum.com/viewtopic.php?f=3&t=15088&start=0

 

"Although I am not an AVTech expert, I am pretty sure I know what happened.

Windows will write a disk signature when it detects a new disk. The 4-byte signature is located at offset 0x1b8 from the start of the Master Boot Record (physical sector 0).

 

AVTech, and others (ICRealtime Pro for instance) do not partition the disk the way a standard operating system would. They seem to write to the raw disk. If one were to use a disk sector editor and put those bytes back where they were, then the disk should be usable again. That value should be all zero's, but could be verified by checking a good DVR disk.

 

The bad news is that it sounds like the DVR went ahead and setup the disk again when you put it back in. In that case all the indexes would have been wiped clear. It would take someone with detailed knowledge of the AVTech file structure to recover it then. "

 

As I've already written thanks a lot for your time.

[rory 0]

Ok so you made me do it ..

I took out my hard drive from the Avtech and placed it in my PC ... with Windows XP SP2 ..

Windows wants to initialize it but ofcourse we cancel that ..

In Windows Disk management it sees it but sees it as unknown and no partitions.

 

So I tried a couple other steps ..

 

I made a bootable DOS jump drive and booted to that, then used AEFDISK ... that reads alot of various file systems and partition tables, even NTFS within DOS .. nada .. it sees the disk but sees no partitions, it was unknown partition type. Now granted that is not a new program, but it does handle alot of partition types, it is obviously missing the AvTech one: http://www.bahamassecurity.com/aefparts.txt

 

So I then booted back into Windows and tried something called UFS explorer .. it also sees the disk but sees it as an invalid partition.

 

In Windows and using DriveSnapshot, that also sees it as invalid.

Ive even been able to read Mac partitions using DriveSnapshot, though as an unknown file system it has to backup every sector so that was a no go.

 

So I dont know what kind of partition they are using ... that would be the first step.

 

However, contrary what the member posted in that other thread, I placed the hard drive back into the Avtech DVR and it came back up as normal, and I can still playback video from earlier, no damage was done to it at all.

[mfoolb 0]

Thanks for your time..

 

There are still some other step I can try before failing to recover these videos.. and if someone has the answers for the lot of questions I asked in my posts I'll be very glad.

 

Ciao.

 

--

Marco.

[scorpion 0]

I too read that other post. Not having any experience I left my posts out of that thread.

 

I am thinking that the data is there. I am thinking that the time was changed on the DVR, and when the hard drive was put back in the time on the DVR and the time stamps on the hard drive were out of sync.

 

In other words you cannot do a search to find the files that you are looking for.

 

I do not know their situation.

 

I do believe you can stick that hard drive back in and even though you may not be able to search for video you will be able to play video.

 

You may be able to search for a "date time group" and try to figure out what the time difference would be.

 

Based on a time difference you can enter date time groups that get you to the actual video that you are wanting.

 

I have seen this with people who change the time group on the DVR for winter fall back, and spring roll forward.

 

Whether this is your situation or not I do not know, but how would this work for you?

 

Can you press play and see the last recorded video?

Can you rewind and go back in "time"? I realize that it may take a long time to get to video that you actually wanted, but that may be the only way.

 

What do you think?

[mfoolb 0]

In my case the problem is that the original hdd was extracted from the DVR forcing the cabinet lock.

 

I cloned the disk and tried to recover the video from the DVR but it say "HDD not found"; the 772 manual states that the cabinet lock must be working and set to close for the HDD to work.. so this is the first path I could follow. (I probably just need to close the circuit to simulate a locked cabinet)

 

I'd also like to investigate on the *proprietary* partition/filesystem of AVTECH products, I can't believe with so many of their products in the market noone has ever tried to understand this better.. I thought this forum could have been frequented by some guy with good knowledge of this.. If we understand how to access the data the process of video recovery become very easy (I'm sure AVTECH uses standard audio/video file formats).

 

Do you know of any other forum where I can find some information on these topic?

 

Last question.. Can you suggest any online shop where I can find CPCAM 773-M DVD at very low prices?

 

Thanks again..

 

Marco.

[rory 0]

Honestly I try not to use the Avtechs anymore .. the video quality is not that great .. but its a cheap unit .. you get what you pay for. If we are going to spend time on something its more like Geovision or something like it which has better quality recorded video and more features. Im sure in many instances with the AvTech and similar DVRs, the clients just give the cops the entire DVR and buy another, its so cheap anyway

[jin_evil22 0]

same as me i also tried this with avtech dvr have 500GB HDD which is not shown in my windows or Linux

[travelmate 0]

it`s easy to restore some files, look to my thread: http://www.cctvforum.com/viewtopic.php?f=3&t=28710

 

But now, i have no idea, for stream...

[Arash 0]

Hi guys!

 

We have the same problem. I had an AVTECH KPD674B that we changed the hard drive in.

 

Now we have a 1TB hard drive with the AVTECH recorded videos in it. This new hard drive has been formatted for windows (the AVTECH hard drive was, I believe, formatted with Unix). I asked a computer company to extract the files for me and put it into a normal SATA-hard drive that I could mount in my external SATA hard drive dock and connect with a USB-cable to any computer for easy access.

 

Now I have all the survaillance files available, almost 1TB.

 

The configuration of the files in the hard drive is as follows:

 

First there are folders with dates, YYYYMMDD

 

Inside that, there is an audio and a video folder

 

Within those folders there are numbered folders, e.g. 1, 2, 3, 4

 

Within those folders, there are files, varying in size, mainly named "stream" in the file format. There is also a db-file etc. The stream file format is used both for the video files and the audio files.

 

I have not found a player that will play the *.stream file format. I have opened a stream-video-file with notepad to see if I can get any clues on what sort of file it is, but it looks encrypted, all of it. I have tried to open it with VLC, WMP, Quicktime player etc., but no luck. Also tried renaming the file format to avi and mpg, mpeg etc. with no luck.

 

What puzzles me is that the system is completely keeping video file and audio file seperated in different folders, and also in different folder configurations. E.g. when I am looking at a specific date, I might have only one video folder (nbr. 1) but four audio folders (1, 2, 3, 4).

 

The video folder in that case contains 10 video files and each of the audio folders contain 10 audio files, so 10 video files total and 40 audio files. I don't get it. How are they supposed to be synced? Looks more like an effort to complicate things and make specifically this type of recovery/backup operation impossible, rather than being the most optimal solution for the product itself.

 

Has anyone gotten more progress with this?

[softip 0]

Hi Guys,

If no luck yet then try this:

 

DVR uses linux OS, connect your HDD with your windows based computer. Download Ubuntu Desktop OS, burn a cd and run ubuntu OS from CD, please remember dont install ubuntu. From ubuntu desktop, open your DVR HDD which you have attached to pc. You will find a couple of folder e.g. backup, lost files etc. alongwith loads of files. These files will be of same size. Copy these files onto a separate hdd, you may copy that to your computer HDD.

 

Restart your PC in windows mode again, remove ubuntu cd. Rename all files copied from DVR hdd extension to .tdb.

 

Now download software from:

 

http://www.web4all.co.uk/TDxScreenLib.zip

 

Run this software and click on eject (2nd right down corner) button which is OPEN button in reality. Select your .tdb file and play.

 

DVR Video files are multi channel video files, so can be played by this player only, as Its a multi channel player, while viewing you can select camera by double click on it from main display screen of player.

 

Happy techs!!!

 

Enjoy, any question?????