12 Cams @ 640x480 3-5fps How Possible & what kit needed?

Mark Ward · Post by **Mark Ward** » Tue May 23, 2006 7:54 pm

Having seen some 320x240 captures I'm pretty sure I'd ideally like to go for 640x480 sized images.

I'm intending to have 12 Cameras in the end, 8 Regular composite off 2 x 4 Port 4 Chip Capture Cards and 4 X Wired IP Cams.

How realistic is it to attempt 12 Cams at say 3FPS and 640x480? Storage space isn't an issue.

Would my Athlon 3200+ with 1gb Dual Channel Memory be sufficient processing power?

I'd rather not do this...but would I be better off installing 2 separate ZM servers?

Thanks,

Mark.

Flash_ · Post by **Flash_** » Wed May 24, 2006 6:46 am

I think that will be ok - possibly another half gig of ram to make it a little more comfortable, possibly another whole gig if those are colour streams.
Also whether you use motion detection or record-directly has a big impact on the cpu load. (Modect on large res is quite a demanding thing)

I run seven IP cameras on a 3200 Athlon-64 single-cpu, but connected unusually. Six of the cameras are connected TWICE - once on modect (at 320x240) and once on record (640x480) - both b&w. The seventh is record-only (colour), so as far as Zoneminder is concerned - it's watching 13 cameras simultaneously and remember, these are IP-cameras which are more intensive than the analogue ones on a good card.

My load is now balanced fairly normally around 0.82 bouncing to 2.0 when I get a couple of modect alarms, but it took some tweaking along the way.

So my view: That spec will cope fine, but you may need to spend some time balancing to get a smooth load and tweaking the linux base system doing things like rescheduling updatedb and backup scripts so they run at a time which won't impact Zoneminder in full flow - or restrict those scripts to a high nice value so they run longer but less demandingly.

Mark Ward · Post by **Mark Ward** » Wed May 24, 2006 10:02 am

Thanks for that Flash, it'll be awhile before I get to 12 cameras, I just thought I'd rather build a meatier server now if I'm going to have to. That's great advice about multiple connections to the same camera, I can see some advantages to that.

Hopefully I'll be OK with some extra RAM.

Mark.

jameswilson · Post by **jameswilson** » Wed May 24, 2006 12:59 pm

you probably wont be using 640x480 on your composite cams anyway as you will get interlace combing if you do so before you setup everything at 640x480 try one and see what its recording quality is mate

Mark Ward · Post by **Mark Ward** » Wed May 24, 2006 4:39 pm

you probably wont be using 640x480 on your composite cams anyway as you will get interlace combing if you do so before you setup everything at 640x480 try one and see what its recording quality is mate

I'm going to order a Sony CCD Camera to give it a try first. There are .25 versions and for a little more money .33 CCD versions. Are the .33CCD one s worth the extra money if we're limited to recording at lower resolutions anyway?

I've got the input card on the way, I just want 1 X Composite & 1 X IP Cam while I discover what's possible.

Thanks,

Mark.

jameswilson · Post by **jameswilson** » Wed May 24, 2006 4:47 pm

well ahem
In the days of vcr's
we all used to use wither vhs (240 tvl colour) or svhs (supossidly >400tvl) and cameras were either med res (380 tvl b/w/330 colour) or high res (570 tvl b/w 480 tvl colour). Now as you could only resolve 240 on vhs why use high res cameras?
Well you do end up with a slightly sharper image from high res kit even though your only recording the same actual number of pixels, i assume its to do withthe way the camera makes 380 tvl source into a 625 tvl transmission but i dont know.
I would say always go for high res where possible (on the cam front)

Note on format sizes 1/4 1/3 and 1/2 inch ccd's all have (or can have) the same number of pixels. As most cctv is made from camcorder chips we tend to follow that industry, thats why the really specilist cctv are so much money (1/2 frame transfers etc).
Even though a 1/4" can produce the same number of pixels a 1/2" chip can it needs a lot more light or gain to be able to do this. This is why cheapo cams have led's on them as they use 1/4 pickups and through their own light rather than 1/2 which can use clear starlight. Id go with a 1/3 as its a good balance between cost and low light performance. But if you have the light it matters little. Plus the smaller factors need cheaper lenses so you can save there!!

Regards