*.dad files

Using PhotoRec to recover lost data
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Joined: 20 Feb 2015, 18:12

Re: *.dad files

#21 Post by unclecolly »

Hello - first post and new user. Thank you for great software.

I stumbled upon this thread while trying to recover video files from a DVR hard disk. I initially tried using testdisk to discover any lost partitions - I didn't have a whole lot of luck with testdisk, but I did have luck with photorec.

My results are similar to the original poster: tons of .dad files recovered from the drive using PhotoRec WIP7.

DVR: Q-See QC444 (I believe this is the same manufacturer as the Micae.)
HDD: 500gb removed from DVR in USB enclosure. The DVR is unable to locate any recordings on the hard disk)

I am wondering if recovering the end result we are looking for (a viewable video file) would be more successful if we instead searched for .dav files.

.dav is proprietary video container made by Dahua for use in their DVR technology. I believe Dahua makes both Q-See and Micae. I think that the .dav container may contain clues about the relationships between the .dad files.

When files are exported to a backup hard drive through the USB output on the DVR, they are exported as hour long chunks for each individual camera. Perhaps the .dav file contains the references to the constituent .dad files?

I have samples to provide, but they are pretty big. I would have to share a dropbox link. Please let me know if you can help me with this.

I do not know how to do a hex dump in windows, but here is the first few lines from a .dav file using notepad. I noticed that it also starts with "DHAV." The file is about 223 mb and can be played using Smart Player by Dahua.
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Re: *.dad files

#22 Post by cgrenier »

If you want to recover a .dav, you can try this signature in photorec.sig
"dav 0 DAHUA"
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Joined: 22 Feb 2018, 19:12

Re: *.dad files

#23 Post by bladzok »

I also got a lot of *.dad files.

How do you view the video in those files?