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CCTV project update; another classic mistranslation
The Q-See DVR arrived today, and I think I may finally have a working system now - minus motion detection. I hooked the DVR's quad-screen output up to my TV card, with an app pushing a frame grab to the web server every 60 seconds. Geeking out pretty bad here, I know. The web image looks like junk, mainly because of the analog-to-digital-to-compressed-jpg that the image is going through before it is uploaded. The actual individual camera feeds are being recorded in full-screen, and they don't look all that bad when things are lit well. The camera looking down at the car is having trouble getting its infrared beam to show much of anything there at night. I might experiment with some IR LEDs installed closer to the street to see if that helps.
So, in the end I dropped $100 on the DVR and another $60 on a 320GB IDE hard drive from Tiger Direct (the DVR didn't come with a drive). Including the cameras, this whole system came to around $250. (I wasted about $60 messing around with the PC and USB DVR cards). With the DVR recording full-res video at 30fps on four channels simultaneously (over 7 days of continuous recording on my 320GB drive), this setup actually may have some application as a cheap mobile system for observing (or just vehicle security). Four camera views and you'd never have to worry about tape running out.
As for the motion detection - the noise on the camera feeds wasn't a problem for the PC webcam software, but too much for the DVR's built-in detector app. It would trigger and record constantly on one sensitivity setting, then not detect any motion at all on the next sensitivity level. So, I just have the thing recording continuously. But as I said, it will take 7 days of recording to fill up the 320GB drive at 4 x 30fps, so that's doable. I think I'm going to turn down the framerate to 15 or 10 fps to double or triple the capacity.
So, to summarize this saga - if you need CCTV, a standalone DVR looks like the minimum that you can do to get something working reliably with multiple cameras. Just stay away from the PC and USB cards, they are all junk.
The best mistranslation ever?
This is what happens when people rely on the automatic web translators too much.