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Re-purposing a dvr

Posted: Sun Oct 15, 2017 11:30 pm
by cshort1987
Is it possible to remove a current DVR software, let's say on a Zmodo dvr, and install zoneminder?

Re: Re-purposing a dvr

Posted: Tue Oct 17, 2017 1:30 pm
by bbunge
If you can install a Linux distro on the DVR and it recognizes all the hardware you should be able to then install Zoneminder. You could have problems if the DVR does not have sufficient RAM or a poor processor.

Re: Re-purposing a dvr

Posted: Sat Oct 28, 2017 6:08 am
by camroidv27
I fear that this will most likely be impossible. Most off-the-shelf DVRs are simple devices. They use SoCs, and are ARM/MIPS based processors. Yes, they are running linux most of the time, but writing new software to the SoC would be as difficult (if not more) than trying to install a custom ROM on an Android device that has no support from the community. From my research (and trust me, EXTENSIVE research... I used to work for these guys looking at these DVRs: http://dmeforensics.com/Technology/DVRExaminer), the OS is not installed on the Hard Drive of the DVR. Add on top of that, Zoneminder would need to be built from source code to run on ARM/MIPS as it is currently running on Intel based architecture.

Sure, I would LOVE to be able to re-purpose some of the cheap DVRs that are out there into something much better than they started out as, but the unfortunate part is that they are just too locked down. Best bet, find an older PC and work with that. Universities and schools usually some decent older PCs that would fit the bill for as cheap as an off-the-shelf DVR.

Re: Re-purposing a dvr

Posted: Fri Jan 19, 2018 5:20 pm
by stoatwblr
It may not be as difficult as you think.

Most of the low end DVRs and NVRs are using a software package built by XiongMai Technologies that consists of a Linux distro, monolithic package containing webserver and DVR, and a logo package.

The DVRs and a lot of the IP cameras/NVRs are built around HiSilicon Hi35xx SoCs - I'm trying to negotiate with Huawei Europe to get the SDKs for these opened up to all comers and GPL complied with but there are some bad attitudes to deal with: 1 "It's too hard, won't do it" and 2: "Linux is free open source,. We can do what we want with it" - both are hard attitudes to shift.

The firmware packages have been unpacked and modified by the hacking community already (they're wrapped cramfs packages), but the monolithic "Sophia" binary (which contains the notoriously buggy uc-httpd amongst other goodies) is still a bit of a mystery. It does seem to contain a bunch of GPL symbols though. - it's this part that needs to be checked to see if it's doing anything fancy with the cameras or if all the AHD etc functionality is in the hardware.

Ironically XiongMai are fully breaching GPL on (at least) the lnux distro yet complain loudly that their intellectual property is being "stolen".

Re: Re-purposing a dvr

Posted: Fri Jan 19, 2018 5:46 pm
by stoatwblr
You're right that the OS is running in FW, but that's relatively easy to update. SDKs _are_ available.

One of the more annoying things about these DVRs is their insistence on using proprietary filesystem formats (Hikfat, WFS, etc) for the storage media - which is where all your time and effort at DME went. It does raise the question of what the ideal format is which should be used. Presumably Hik and Xiongmai went to these proprietary ones because fat and ext2/3/4 aren't good enough (then again, they could have just been looking to avoid exfat licensing fees)