Using video cameras to catch taggers and thieves
Like many people in Los Angeles, I've had my house tagged and things
stolen from my car several times, and I wondered whether security systems
could help.
Personal Experience
I'm trying out a home video security system to see if it is effective in
nabbing bad guys.
Experimental Setup
A Lorex
L19WD800 system, recording 352x240 resolution video, with four "450 line resolution" analog cameras, was installed.
Our garden wall and gates are on the north side of our property.
At each of the two garden gates, two cameras were mounted, one
facing northeast, one facing northwest.
The Lorex
bundled software was installed on a Windows computer and used to extract
.avi files when needed.
Recorded Crimes
The camera system recorded the following crimes:
6 June 2010: Wall tagged.
Video, stills, and writeup here.
28 Aug 2010: car radio stolen.
Video here.
Still pictures
one,
two,
three.
4 Feb 2011: garage door tagged.
Video here,
here, and
here.
Still pictures
one,
two,
three,
four,
five.
Happily, these were good enough that showing them to the principal of the nearby completion school allowed her to identify the taggers.
14 Feb 2012: garden wall tagged. See writeup
here.
16 Aug 2013: Neighbor breakin; see writeup with video
clips.
Results
Of the five crimes observed, only in one of the five cases was the video good enough to identify and catch the offender.
Observations
- Two cameras per gate was a good idea, as the field of view of each
camera is not very wide.
- The bundled software for extracting .avi files was tedious to use.
It takes several hours to identify and extract the relevant footage
and save a few still images. One must repeatedly enter in exact time
codes and figure out strange user interfaces, and download an extra
third party tool (e.g. Media Player Classic) to save still images.
- The .avi files exported by the bundled software are lower quality than the video played back on the DVR's built in screen.
- Still images extracted from the .avi files are too poor resolution
to identify people well.
- The bundled software was Windows-only, which is inconvenient, since
most of my computers run Linux.
Resolution bottlenecks
Both camera and video recorder limit the resolution of the recorded video.
Buying a higher resolution camera, like the
Lorex lbc6050, won't do any good if the video recorder only supports
352 lines.
It looks like more recent Lorex DVRs support 640x480 recording.
References
There have been a number of studies over the years about whether surveillance
cameras actually reduce crime. Here are a few links:
