Not yet rated
Loading ...Digital CCTV Surveillance for Next to Nowt
eschatonic
Digital CCTV for Next to Nowt Part 1 - The Strange Case of Cheapest is Best
This blog is about building a digital CCTV surveillance recording system, as the title suggests, at as small a cost as possible. Generally speaking you get what you pay for and I had no intention of spending very much so my expectations were set pretty low. At the risk of spoiling the plot, this blog has a very happy ending.
Down to business. Clearly the elements to this system are: cameras, some kind of computer, a means of storage, some way of linking all the bits together and, of course, the software to run it all. The first element of this jigsaw that I focussed on was the category ‘linking it all together’ and in particular how to get video into the computer. In my particular case going wireless had great attractions in terms of both convenience and cost of wiring but in either case the result is the same - by the time the picture gets to the computer it is analogue. This is a bit odd really since the TV picture starts out its life as a digital image. The CCD (charge coupled device) inside a video camera is an analogue shift register that shunts, by a clock, a frame store of electronic signals through successive stages of capacitors effectively delaying and serialising parallel analogue signals. The CCD itself is not responsible for the actual imaging which is done by photodiodes.
Any road up, you wind up with a bit of electric string that typically ends in an RCA plug (on cheap systems) or a BNC connector. In the case of
Britain and NZ this will have an PAL analogue TV signal on it. The problem then becomes how to turn that picture back into a digital form that can be manipulated and subsequently stored. So I looked around at what I could get at an affordable price. This wretched little ad caught my eye on the NZ auction site TradeMe: -4 channels PCI DVR card
-Simultaneous 4 cameras recording onto the hard drive in the PC
-Continuous, Scheduled or Alarm trigger motion detect recording
-4 BNC connectors
-Support PAL or NTSC, select option during installation
-Remote viewing
-Works with Windows 98/2000/XP
-Minimum requirement, Pentium P3 500Mhz, 256MB and 20GB hard drive.
Will work with any CCTV cameras
That was it. No picture, no spec – literally no shit. So I bought it for $30NZ (£12). I expected the worst and my expectations were further lowered as the board took weeks to arrive from
Australia.
But look what turned up!
This is obviously a very tidy and workmanlike board. It just doesn’t look cheap and cheerful. For some reason the retaining bracket was separate but the screws for attaching it to the board were included so what the heck. Take a look at the top left of the card as viewed. See the little black block? That’s an audio connector. Hmm no mention of that in the silly advert and on the top edge of the board there are two blocks of pins – again not mentioned in the advert. In the same package was a baby CD.
It turns out that this board is much more capable than the ad suggests. As well as the obvious 4 video channel inputs there is a single audio input and a set of alarm inputs and outputs.
It turns out that the feature list looks like this:
DSR provides multi-channel video recorder, multiplexer and video transmission server functions Support both PAL and NTSC standards Support full resolution video (768×576 PAL, 640×480 NTSC) Provide real-time digital video compression Provide configuration retaining Provide status retaining for auto start Easy to use graphic user interface Easy to expand by software upgrade and system integration Multilingual Capability Support up to 16 camera inputs with multi display modesState of the art real-time display and recording under optimum condition of up to 4 channels Programmable timer for recordingProvide circular recording mode to allow recycling use of the recording drives Provide archive-recording mode to allow directly recording to a specific removable driveAudio recording with a selected camera Pan/Tilt/Zoom Control (selected Protocol) Video Playback & Search Simultaneous playback and recording Playback with sophisticated search functions (by camera, events, time/date)Snap shoot with print and save Alarm & Motion Detection Alarm I/O interface for alarm triggered recording Motion detection recording Pre-alarm recording Scheduled alarm and motion detection function Remote Playback & Online ViewIntelligent remote player through telephone dial up, LAN and Internet connectivityVideo transmission server function provide online viewing of live video with password logon control and event logRecording in remote client machinePlayback recorded videos (both local recorded and server recorded files) Alarm alert function Pretty impressive huh!
Clearly the majority of these features relate to software which at this stage I had no idea was included with the board. Result!
But will any of it work?
CCTV is UseFul For People..