A small system could definitely be done with a single core netbook. Dual core atom netbooks have reached the market (swordfish).
(Later - now that I've discovered multi-TT hubs a net-book or note-book may work.)
(Even later - the MTT hub arrived and it made no differnce .)
This page is mainly about a product called "Blue Iris". I have no special relationship with Ken Pletzer, blueirissoftware.com or Perspective Software.
I do not sell anything or offer consulting. I'm simply sharing my experience hoping it will help others and catch some thieving scumbags.
Here in the Brisbane area a significant number of homes get burgled a second time - usually about a month after the first time. In my case is was only two weeks but there were special circumstances.
It is better to be prepared and not need it than miss the chance to catch these bastards. I think someone (police?) should make surveillance equipment available to people at risk of a repeated break-in. Either we'd catch some crooks or they would learn not to come back - both are good things.
There plenty of products on the market but I've found them pretty lame.
Cameras etc can fill several needs and some are contradictory. You may want to deter criminals or you may want to catch them - where you stand on this may change from day to day.
For deterrent value cameras are visible and warnings signs etc are in view. To catch them the cameras are hidden.
I think it is important to see who is snooping around and to see suspicious actively before a break in occurs. Even if the crims decide to go to another house your images may help solve somebody else's problem.
I'm not in loop as far as criminal logic but I think it is likely they will knock on the door first to see if someone is home. They are not likely to be in balaclavas at that point.
If you have an acute situation and cheap PVR type system may be some comfort and may do some good but for a long term use a roll your own system is better value - provided you have some basic IT skill or help on hand.
Cheap PVRs do not have (true) high resolution cameras, web interfaces, email alerts or online file backup. For similar money you can set up computer with all these features.
PVRs and IP camera sold as high resolution are usually only 640*480 - pretty mediocre by most standards.
Almost anything is better than nothing - it you in a high risk group get something set up - even one low resolution camera is better than no camera.
Clearly I'm not going the post all the details on my security system online.
I've tried two wireless IP cameras which work to some extent but have problems.
Both were from Jaycar.
The first was a $150 "grandtec". The bundled software was marginal but had a few cute features. It was a fairly dumb camera with image processing done on the PC not the camera. The killer was the camera crashed repeatedly and I returned it after one day. I also would sent bad video frames every 5 minutes or so and this would trip the motion detector.
What I though was cool was the ability to take a time-lapse movie which slow to real time when motion was detected.
The other camera appears to be the same as this http://www.starvedia.com/ProductDetail_ic202w.html
It was $250. This camera has a built in webserver and can do motion detection in camera. It can send email alerts etc without need a PC. This camera is much more stable but motion detection fairly useless except for indoor artificial light situations. It in camera motion detection can not be set to mask out unwanted areas and the detector will trip with when lighting conditions change slightly. For example in a room light by ambient light a cloud coming over the sun will change the interior lighting enough to trip the detector.
The bundle software is marginal and stores video-clips in individual non-standard files making it very difficult to see at a glance what you've captured for the day.
They also make it very difficult to use 3'rd party software such as blue iris because they hide the details of internet camera from you - you are just supposed to run their software which for me is pretty useless.
The image quality of these cameras is not great. What is considered hi-res (640*480) for an IP cam is fairly poor. As well as being marginal in resolution there are lots of compression artifacts.
Wireless has its advantages but if you can cope with using wire a very cheap webcam will work just as well and a high-end web-cam will be far superior.
I also spent a lot of time trying to get zoneminder to work. Zoneminder is an opensourced linux package which looks quite good but seem to require guru status to make it work. Even after buying a webcam which is known to work with ZM I could not get an image.
Yesterday I downloaded a trial version of "Blue iris". This is a windows based product which looks very good so far. I had cameras configured within minutes and all my webcams work. My logitech 9000pro produces very sharp images and can record video at up to 1600*1200 pixels.
This package has almost everything and is only $50US for the full version.
A problem with both packages is they require a lot of PC resources. Running a lot of cameras requires a powerful computer. Running say 8 cameras at reasonable resolution and frame-rate will need a fast multicore PC.
BlueIris includes a DDE (direct data exchange) server which can be used to trigger or control it from other programs. I cover this on the BlueIris DDE page.
Clips and images are backed up via FTP is case of computer theft.
The system isn't perfect but the odds of catching a thief have greatly improved.
One minor problem is that I can't turn the system off before I enter the house. This is no drama while I'm the only one receiving alerts but ideally alerts would go to multiple recipients.
Later, opps alerts were disabled on one machine.
The good news is the PC monitoring the front yard didn't register any false triggering all day despite a lot of traffic in the masked out part of the image. It did record me checking the letterbox on one camera and entering the room in the other.
To use the aspire-one I'd need to add IP cameras. With a mini-PC I could use an analog video capture card. A regular PC with lots of spare bus slots would be the most versatile at the expense on needing more space and power.
Later, caught a courier trying to make a delivery to my front door. The system works.
http://www.smsglobal.com . For small users the cost is 10 cents per message and the smallest lot of credit is $10 ie 100 messages. Another bonus is you get 25 free credit when you sign up. It took a while to nut out how to set up the account I but got there in the end. My SMTP server is in the US - the other side of the planet from here so. I'm not sure where the gateway it physically located. Anyway I haven't timed it but the time from sending the email to my phone beeping is around 10 seconds - fast enough the catch a crook in the act.
I had to tackle two issues. The first is my ISP blocks port 80 just to be difficult. The way around this is to use another port number and set up my router to forward this port to port 80. How to do this will depend on the router - it is fairly easy to do on my dlink. It is a little difficult to test because you need to be on the other side of the firewall.
The other issue is that I don't have a static IP. The way around this is to use a dynamic DNS service. You can set up a free account with a service like dyndns.com but a pro account is only $2 a month.
Once you have an account set up you can use a URL such as http://username.dyndns.org:82 ( not my real address) to access the home server. Dyndns has to know what IP address to translate this to and this is either done by the router or by running a DDNS update program on the PC.
To get a psuedo static IP address to connect to - I uses the camera's wifi MAC address to reserve an IP in the router.
I have maybe eight different cameras and some of the results were a little unexpected.
For best image quality to prize goes to the logitech pro9000. This is a high end webcam with sound. It boasts Carl Zeiss optics and the lens quality shows. It can stream video at 1600*1200 pixels but even at low resolution the images are sharper than all my other cameras set to the same resolution. It is a 2MP sensor but the results are sharper than my 4MP cameras.
The down side is it needs fairly bright light to get good results. It is also useless over USB-1.1 Some other camera will give me 640*480 images over USB1.1 this camera won't. I can connect but can only get thumb-nail sizes images.
At the other end of the scale is the $20 Logitech Quickcam For Notebooks. This is a 0.3MP camera and as you might expect the image is limited to 640*480 and the quality is not great. The up side is they work better in poor light than the hi-res cameras. However this camera can not cope with sunlight. Sunny outdoor image come out almost white.
My midrange logitech (which may be a Logitech C100) has other problems. It sometimes varies its brightness for no good reason and trips the motion detector. Otherwise it would have potential as a low light camera.
The 4MP microsoft lifecam hd 5000 gives fair quality but the autofocusing seems to get into refocusing at the wrong time and misses the action.
Microsoft LifeCam VX-5000 is a fair low-light camera but the camera is not focused at infinity. This is probably true for many other fixed focus webcams.
If you need more than (about) three cameras or more than one hi-res camera it appears you need expansion slots or some other way to add more controllers (not just a hub). USB3 may change all that shortly.
USB cables are limited to around 5 metres in length (it can be hard to actually buy long cables).
In theory you can use a hub to extend another 5 metres and repeat the process to give a total length of 25M.
There are also USB extenders which use cat-5 ethernet cable. I have one as a 40M extension but seems to be USB1 and you can't run a high-res camera through it.
Here in Oz - jaycar sell five metre and ten meter active extenders. These are basically a single port hub built into the cable. They claim you can cascade two for a 20M link. I've tried five,ten and five plus ten metre cables and they work fine. I had no luck with running and extender with a hub - maybe I need to spend more than $4 for a hub.
Later I managed to run three cameras off a hub on a 10M extension, the fourth wouldn't run.
It is all very flaky though. I can make the hub and cameras work but they stop working after a time (hours) and require a reboot. This is using a Via rev 5 (or later) based PCI USB adapter. Strangely one camera which is directly plugged into the adapter keep working while another fails along with the one(s) on the extender. It seems to be related to the PC standby/screen-saver mode but it is hard to pin down.
Much later - replacing the VIA based PCI USB card with a NEC based "swann" card fixed the above mentioned problem.
At $40 for 10M and $25 for 5M these cables add a fair cost to a long link. Low-end wireless IP cameras may work out cheaper for long links but the image quality is terrible.
With a centrally placed PC and one extender per remote camera you can cover an average size house pretty well.
Apparently there is a problem because the cheap cameras run at 12 megabit (usb1.1). If I had full speed USB2.0 cameras my problem might disappear.
Single-TT or Multi-TT
Also using multi-TT hubs could make a huge difference. It may be important not it plug a USB1.1 device into the PCI or on board controller either.
Google "multi-TT" and be confused.
My understanding is a hub with a single TT (transaction translator) will share the 12 Megabit/sec between all the USB1.1 devices plugged into the hub.
I have also read claims that a USB1.1 device when plugged into a hub will force all devices to work at USB1.1 speed. This sounds unlikely but may be true for some hubs. There are similar issues with USB1.0.
Actually finding a multi-TT hub has proved difficult. Very few adds even mention TTs. Multi-TT is implied in some of the specifications with actually saying it.
On a similar note it is hard to know what device talk at USB2.0 speeds. Being USB2.0 compatible doesn't always mean the device can talk at 480 megabit/sec.
The "Cables Unlimited" USB-1870 is one multi-TT hub - I can't find any in OZ except at ridiculous prices or from the US with ridiculous freight charges.
Cheap cameras could prove to be more expensive overall when the cost of extra USB cards or multi-TT hubs is factored in.
Most hubs have the option of plugging in a power supply to avoid overloading the computer USB port. This may be handy but complicates battery backup options(UPS). I've found that even with a MTT hub I can only run 4 cameras off one USB controller and that I can run those cameras plus extenders and remote hub without needing external power.