But then you would need an IR camera instead of using the phone's camera. An IR camera should be able to find some hidden cameras passively by detecting a heat source.
There are SWIR, MWIR, and LWIR cameras among IR cameras. SW is just regular camera with the filter removed and they can't see heat. Somewhere between SWIR and MWIR are uncooled IR cameras that use MEMS heat sensor ish arrays built on top of a camera sensor that can actually see heat by differentiating between previous and current frames, with the caveat that they cannot do it indefinitely but must use a mechanical shutter to periodically cool down to operational conditions.
MWIR and LWIR cameras are often cooled and uses more exotic sensing mechanisms, sometimes even vacuum tube based, nowadays usually semiconductor based but not regular CMOS. Some require mechanical shutters obscuring view every other frame(that, I think, is where BHOT/WHOT switch came from; it must be switching whether to show odd or even frames).
You need the MEMS types or better to see heat; they're more often referred to as thermal cameras than IR cameras. They are also unable to see through regular soda-lime glasses, that might pose its own challenge as well.
Depends on how cheap you go - most of the cheap ones that take images where the blacks look grey likely do not have an IR filter on them. Most quality phones will use a camera with IR filters on them - blacks look like blacks.
Perhaps to avoid tipping off the entity recording you by blasting their hidden cameras with bright lights. Granted, the PoC device in the article is not exactly subtly looking, but if you could turn it into a sleek device it would be more useful. Not playing your hand while you're under surveillance lets you control the information they're receiving.
Though the bigger issue with my theory is that while most cell phone and webcam devices have IR filters, many surveillance cameras intentionally do not.
If you're being surveilled in a way that you don't want to tip the observers is one thing, but if you're in an AirBnB type place, fuck 'em. I'd even be fine with running some lasers in the place that ruins the sensor.
Walk around your neighborhood and see who has security cameras.
Security camera through PVS14 https://youtu.be/gEWniEhtE2k
But then you would need an IR camera instead of using the phone's camera. An IR camera should be able to find some hidden cameras passively by detecting a heat source.
There are SWIR, MWIR, and LWIR cameras among IR cameras. SW is just regular camera with the filter removed and they can't see heat. Somewhere between SWIR and MWIR are uncooled IR cameras that use MEMS heat sensor ish arrays built on top of a camera sensor that can actually see heat by differentiating between previous and current frames, with the caveat that they cannot do it indefinitely but must use a mechanical shutter to periodically cool down to operational conditions.
MWIR and LWIR cameras are often cooled and uses more exotic sensing mechanisms, sometimes even vacuum tube based, nowadays usually semiconductor based but not regular CMOS. Some require mechanical shutters obscuring view every other frame(that, I think, is where BHOT/WHOT switch came from; it must be switching whether to show odd or even frames).
You need the MEMS types or better to see heat; they're more often referred to as thermal cameras than IR cameras. They are also unable to see through regular soda-lime glasses, that might pose its own challenge as well.
Can’t phone cameras pick up IR?
the raw sensor can, but there's usually an IR blocking filter in the lens assembly.
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I’d think so. My iPhone can see my remote’s IR.
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Depends on how cheap you go - most of the cheap ones that take images where the blacks look grey likely do not have an IR filter on them. Most quality phones will use a camera with IR filters on them - blacks look like blacks.
Pining for the days when phones had IR blasters (e.g. galaxy s6); that would work perfectly for this
some more modern phones from xiaomi still have IR blasters
Why would that be more useful?
Perhaps to avoid tipping off the entity recording you by blasting their hidden cameras with bright lights. Granted, the PoC device in the article is not exactly subtly looking, but if you could turn it into a sleek device it would be more useful. Not playing your hand while you're under surveillance lets you control the information they're receiving.
Though the bigger issue with my theory is that while most cell phone and webcam devices have IR filters, many surveillance cameras intentionally do not.
If you're being surveilled in a way that you don't want to tip the observers is one thing, but if you're in an AirBnB type place, fuck 'em. I'd even be fine with running some lasers in the place that ruins the sensor.
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Unless the hidden camera has IR capabilities.
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