April 3rd, 2012 by peter
Typically, security systems use CCTV cameras that send video signals over coaxial cables (like cable TV) to another system which converts the analog camera signal into digital data. The downside to this approach is that the cameras can’t just be plugged into a computer. Special computer hardware or a dedicated CCTV camera system are required to use these cameras. This is not cheap, but there’s a good reason why this is the norm (read on).
Webcams output digital data via USB so that they can be connected to a computer without any additional hardware. Software running on the PC can read image data from the webcam and display it to the user or save it to the computer’s hard drive. The downside to this approach is that the camera interface is not necessarily consistent from one webcam to another. I have a Kodak webcam and a Logitech webcam, and when I plugged them in I found I needed different software for each. Windows 7 handles these differences pretty smoothly, but my donor PC for this project is using Ubuntu Linux, and there things are not so polished. Adding additional cameras would mean having to buy the same camera or fiddling with more software. Now I bet you can see why CCTV systems don’t take this approach (besides legacy reasons). Managing many webcams would be a real headache!
Luckily, network webcams that connect to WiFi or via network cables to your home router are available. Many of these can capture images as standard JPEGs which can be uploaded to a File Transfer Protocol (FTP) server. This method should work for most network webcams. As a big added bonus, there are no wires to run around the house if the webcam is wireless.
After reviewing cameras on Amazon, I decided on the Foscam FI8918. This camera strikes a good balance between cross your fingers and pray no name Chinese brands and expensive name brands. I purchased two for $160 shipped. This is a lot more than the $25 I paid for my Logitech USB web cam, but not having to run cabling through the house was easily worth the $50 difference to me. The FI8918 can upload images to an FTP server and can also be configured to detect motion. It even has a nifty calendar based scheduler built in, though I didn’t intend to use it.
The setup of these cameras is a little goofy, though straightforward. They must first be plugged in via a hard wire network cable to your router. You then need to run a utility on the provided CD to locate the cameras and open Internet Explorer to the configuration page. I changed the default camera name an username/password before configuring the wireless connection. I found that the Foscam’s wireless configuration page didn’t automatically detect my wireless settings, so I had to log into the router and copy all the settings. The first camera worked smoothly after all those changes, but the second stubbornly refused to connect to my wireless. Finally I reset it back to factory settings and repeated the process one more time and all was well. Not sure what happened…
I then setup the FTP upload and Alarm settings in the administration panel. Sample settings are displayed below.
With that all settled, I now needed to actually setup an FTP server! This turned out to be trickier than I thought… stay tuned!
March 20th, 2012 by peter
After hearing stories of recent day time burglaries, we decided to take action to improve our own security.
[Note: we presented about this system at Maker Faire 2012 in San Mateo; the final, polished presentation will be available in a few days online]
Most folks would sign up for ADT or maybe a more cutting edge solution like Alarm.com. But, there are a number of drawbacks to traditional monitoring:
- It’s impractical. The multitude of sensors needed are wired, so you need to poke holes in the walls of your home. You have to arm/disarm via keypad. Also, false alarms can be costly, depending on whether the local government charges for them.
- It’s expensive relative to the value provided. We calculated the cost of the system over 10 years would be about $4,000-$6,000. The average loss in a burglary is $1,725.
- The alarm system does not provide sufficient actionable information. It can detect that a door or window has opened, but can’t provide you information about the identity of anyone entering your home.
It seemed much simpler to look for motion within the home, take a picture, and email it.
Regarding notification, we communicate via email to our smartphones. That’s the same way we’d like to receive alerts. That cut out most of the DIY alarm kits on Amazon such as a the SkyLink SC-100. These only have a local alarm (a noise maker).
I looked up some IR motion sensors, but they all required hard wired installation or a proprietary base station and they aren’t cheap either. I know that webcams can easily do motion detection, and they sometimes cost less than the IR sensors when on sale– so why not use wireless webcams?
The only hurdle would be to distinguish intruders from us, and there is a very easy way to tell when we are home: our smartphones connect to our home WiFi.
Suddenly, an outline of the system began to form. It would be based on a PC connected via WiFi to wireless webcams and basically implement the following process:
- Wait for motion
- Taking pictures of any moving object
- Email a picture
This simple setup would be the start of our DIY security system.