On 23/07/2010 11:19, alan.b.pearce@stfc.ac.uk wrote:
>> Are you sure about 4 million surveillance cameras? Who has the ability
>> to review all of that video? Are all of those just run by the police
>> or is that a total of all security cameras owned by anyone? This
>> figure would mean something like 1 for every 10 people, right?
> Probably not a wrong count. Much of it is video surveillance of shopping
> centres and the like, and goes to live screens in a control room
> somewhere. It may well be recorded, for use as evidence in trials, but
> the recordings are not actively watched later apart from the control
> room staff monitoring it, live unless being searched for evidence later.
> I don't know what the overwrite period would be.
Indeed most is useless for evidence. The Irish police (garda) brought me 
a tape to enhance.

The head was 4 pixels. A cheap 35mm camera connected to Motion detector 
in the warehouse would have captured a suitable image as that is roughly 
2000 x1000 pixels or more.
Most security cameras in analogue days about 1/2 PAL resolution or less 
and after analogue VHS time lapse about 250 x 576.

Modern CCD + HDD are often barely 640x480.

Also there has been no major studies to show how much CCTV deters crime 
or assists in detection or prosecution. I have met people that wanted to 
pay me to fit CCTV and I told them a solid fence at rear was a better 
investment.

I had CCTV to monitor "undesirables" in my driveway. They threw a rope 
up and hauled off the camera! I didn't replace it. Activity decreased, 
maybe they liked performing for the Camera?


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