How many cams realistically supported by Raspberry Pi?

[ksshooter]

I'm looking at turning my Pi into a home security system, using IP wifi cameras, specifically the Dlink DCS930L. I'm wanting to:

• Capture differences in the pics to capture motion, and only really save those images/videos
• Upload those images/videos to a web server outside of my network/home
• Ability to pierce firewall, to view "live" camera pics from my iPhone/iPad/Android tablet, etc.
• Use a "heartbeat" signal that will inform me whenever network connectivity is lost to Pi (this will require programming external web server)
• Use email/SMS to immediately send pics, etc. to email or SMS
• Looking at about 5-6 cameras

I'm assuming that all of the above are possible (seems to be from what I've read so far).

My questions are, at this point:

• What's the realistic number of cameras (DCS930L) that can be supported by a Pi and ZA?
• I know the 930L does not have IR capability - how much of a factor is that, if some battery-backup night lights are used in wall outlets at areas wanting/needing to capture?
• Is there some other IP/wifi camera that is better, and/or cheaper that will also work as well?

Overall, I don't want to spend more than about $150-170USD to get the cameras, etc. Much more than that, and I can buy a "ready to install" system made specifically for my purposes, so the idea is to keep it cheaper. If it simply goes over that, I might as well buy "purpose built", etc.

Thanks!

[mikb]

If the DCS930 is like the DCS900 (640x480 ST-Electronics VGA sensor) then battery powered nightlights won't help you see in the dark. They need decent light to see (aren't the really "indoor" cameras?

They have no IR sensitivity to speak of, the ones that I have that work "in the dark" have been modded 1) To swap the original board-lens for a monochrome (no-IR filter) board-lens, or 2) To swap the original board-lens for a monochrome CCTV CS-Mount lens (mechanical hack) to collect more light.

These still need IR illuminator assistance to work. Streetlighting isn't enough to see in the dark in any meaningful way, so get more light!

[PacoLM]

[*]Looking at about 5-6 cameras[/list]

Even if the resolution for all the cameras is 320x240, I do not think Rpi is able to provide the performance needed to handle all the open processes....not enough CPU and not enough RAM.

PacoLM

[ksshooter]

Thanks for the replies. I was afraid that might well be the issue.

[mastertheknife]

I recommend going with an Intel Atom instead. I have the D525MW board, with 4GB ram and 2 hard drives (grouped together in LVM), running CentOS 6.4 64bit. This small, power efficient box can take a lot at it.

[ksshooter]

As I said, I'd probably rather go for "purpose made" units. For $300-350USD, I can get a completely new unit with all new alarms, etc. for my needs. Just trying to replace a 15-16 year old unit that is a PITA to program, and is starting to give me fits.

I was simply looking into something that might take less $$$ and use a few things I already have. Not sure of the price of an Atom unit (been on Mac the last 7 years), but I'm going to guess that by the time you get the case, P/S, mobo, memory, etc. I'll have about $125-150 wrapped in that alone, and then still need to buy cameras. Not an economically viable deal for me.

Thanks for the idea though.

[mikb]

I was simply looking into something that might take less $$$

Any objection to a small form factor PC, e.g. a small desktop? If you are looking to save $$$, then a 2nd hand PC would be one option. An RPI sets you back £25-£35, and you can get a whole desktop (case, psu, mobo, memory, HDD) for that.

Throw a basic linux install on, bang Zoneminder on top, lock it in a cupboard Like an RPi, no keyboard and mouse needed beyond the inital setup, just ssh into it/web access it for day to day stuff. There's likely to be plenty of CPU and RAM available there ...

[ksshooter]

I was simply looking into something that might take less $$$

Any objection to a small form factor PC, e.g. a small desktop? If you are looking to save $$$, then a 2nd hand PC would be one option. An RPI sets you back £25-£35, and you can get a whole desktop (case, psu, mobo, memory, HDD) for that.

Throw a basic linux install on, bang Zoneminder on top, lock it in a cupboard Like an RPi, no keyboard and mouse needed beyond the inital setup, just ssh into it/web access it for day to day stuff. There's likely to be plenty of CPU and RAM available there ...

It's not just the desktop. I still need 5-6 cameras, and even at $35 a pop, that adds up quick (and I've been told those cheapies won't cut it for night time - so then those cameras are more like $70 each, not $35. And the cameras aren't NO/NC wireless switches for doors/windows, so I've got to carefully position them, then still figure out how to get them power throughout the house, etc. without being overtly obvious, etc. Then you've got the issue of battery backup to keep all of it running, etc. That's easily going to top out at $200 or more - at the VERY cheapest, but will probably break $400 or more realistically. Then I still have to create everything, adjust, etc., and 'who you gonna call' when the whole thing doesn't work? I'm willing to do some work if it saves me a "good enough" chunk of change, but going this route AND buying the cameras just doesn't make sense to me - not when a ready-to-roll system can be had for $300-350 that will provide every switch/IR sensor/fire alarm, etc.

And the other thing is the "day to day" stuff. I want something I don't have to fiddle with every few days, etc. And I'm quite familiar with Linux (been using it since 1995, and professionally/commercially since 2001), and even though those systems can run for 2-3 years without reboot, they still take maintenance and monitoring - even when everything is "stripped down" to the bare essentials. Every once in a while the daemons die off, and you have to restart them, figure out what the problem is, etc.

The other systems I'm talking about take new batteries, once every 3 years or so. That's about it if you aren't expanding the system to include more alarms/zones, which I don't foresee once I get the initial hardware.