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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.

I've found an European company that states it worked with AVTECH video data extraction but as expected they asked for good money. I'm still hopeing I can try to do that on my own. When you say disk should be sent to AVTECH are you referring to AVTECH Taiwan or what? Ciao.

Hi, I was not able to recovery the data from the disk (viewtopic.php?f=3&t=21381). I have some budget and I would like to know if there is any company (Europe) that can recover video files from disk used with the AVTECH model in subject. The disk result empty if used with the DVR but there is around 70GB of data in it. Thank you. -- Marco.

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.

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.

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.

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.

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.