[Gllug] [OT] TFT displays

[Sean Burlington]

Liam Smit wrote:
> 
> Well I assume that they think they will get to the point where there
> will be no devices capable of recording analog. Not very realistic
> seeing as how the world is in analogue so every video camera, sound
> recorder, etc will be able to do the job by virtue of the nature of
> its purpose...
> 
> Not very realistic are they? ;-)
> 


They can't stop all the people all the time - but maybe most of the
people most of the time...

It is often possible to create a system that attacks some vulnerability
of a recording system.


This from New Scientist on a system to prevent photography of museum
exhibits

----------------

The IR projectors illuminate everything within 10 metres, and the camera
detects any infrared bouncing back from objects within this range and
feeds the information back to the computer. The PC can pick out a camera
phone because the light it reflects is brighter than any other
reflections around it. This is because all camera phones and cheap
digital cameras use a "retro-reflective" silicon sensor to capture
images. This means the cameras reflect light straight back to its
source, rather than in multiple directions like most surfaces, so the
reflected light is much more concentrated.

When the PC detects a camera phone, it instructs the ordinary projector
to shine a 5 to 10 centimetre square beam of flashing and
colour-changing visible light directly at it. This ensures that any
photo appears bleached-out as the camera does not have enough time to
adjust its light meter to the changing colour and brightness of the light.

------------

-- 

Sean

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