[HN Gopher] Pentagon testing mass surveillance balloons across t...
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Pentagon testing mass surveillance balloons across the US (2019)
Author : TheFreim
Score : 37 points
Date : 2023-02-12 20:22 UTC (2 hours ago)
(HTM) web link (www.theguardian.com)
(TXT) w3m dump (www.theguardian.com)
| perihelions wrote:
| These freedom balloons or whatever, they have a neat trick I
| remember reading about. In principle, if you're at very high
| altitude, you can simultaneously image everything over hundreds
| of square miles, with the right optics and an extremely large
| camera array (many gigapixels). You're close enough to identify
| faces (unlike orbiting satellites 200 km+ up). And you can stare
| at everything forever, 24/7, except that the firehose of data is
| unmanageable (even just a direct downlink would be impossible).
| So the solution, the trick, is a large FPGA on the balloon that
| classifies small pixel regions, according to whether "these
| pixels are static"; "these pixels might contain a human"; or
| "these pixels are non-static but probably not human". And the
| result is to select small windows out of the firehose for real-
| time downlink, while discarding the rest (or just updating it at
| low refresh rate).
|
| I don't know if this was common knowledge or not: but the effect
| is you can continuously stare at incredibly large swaths of land
| at once, with the illusion of a pseudo-100+ Gbps video feed,
| through the right combination of vehicle/optics/camera/signal
| processing.
| anigbrowl wrote:
| _You 're close enough to identify faces_
|
| I seriously doubt that even with black-projects AI assistance.
| I have no experience with hi-altitude fancy photography, but a
| lot with the limits of terrestrial photography of human
| subjects.
| tonyarkles wrote:
| I work on aerial imaging hardware and... I'll bite, just for
| a few minutes. At this point I'm at 50/50 and just want to
| know the answer at "napkin resolution"
|
| https://www.axis.com/learning/web-articles/identification-
| an... Suggests something like a 2mm-4mm GSD would be
| required.
|
| The small city I live in has an area of 179km^2. Assuming
| it's a square and we're taking a square photo, that's 13.37km
| x 13.37km (nice number!). In each axis this is 13.37e3 m /
| 2e-3 m/px = 66.85e6 pixels. Squaring that gives us... if I'm
| counting right, a 4.4 Exapixel image. If we used the 4mm GSD
| instead of the 2mm GSD it would still be a 1.1 Exapixel
| image.
|
| On a modest budget (maybe $200-300k) the kit I work with
| could be scaled up to do real-time gigapixel imaging at maybe
| 20-30 fps. But that's still short by a factor of 1M both in
| image sensor real estate and in processing capacity.
|
| I agree that this seems implausible. That being said, the
| gigapixel rig could still be quite scary in the wrong hands,
| just not at the city scale. You could do video that covers
| about a 350ft x 350ft area and be able to retroactively go
| back and do face identification on everyone whose faces you
| can see. It's a completely parallel problem too and the costs
| scale linearly with the area unless you start running into
| second-order effects like diffraction limits or obliquely
| angles.
|
| Edit: option 2 now that I think about it a little more would
| be to have a lower resolution broad image with servoable high
| resolution units. Point the 350x350ft camera at a specific
| ROI and filter down from there. That $200-300k budget
| includes about a dozen onboard high performance ML engines.
| Depending on the actual frame rate you want processed, you
| could either do light object recognition at a reasonable
| rate, or heavy inference at maybe 0.5-1fps.
| [deleted]
| moose_man wrote:
| Yes, but notice how they did not test them in Chinese airspace.
| puffoflogic wrote:
| Notice that we have zero evidence that the recent objects were
| Chinese in origin except the admin has said so. And we know
| they never lie about anything.
| more_corn wrote:
| It would be funny if they turned out to be ours. A case of
| the right hand not knowing what the left hand was doing.
| moose_man wrote:
| The Chinese said it was their balloon last week. They want it
| back. If we just go with the prevailing trend, China is the
| most likely explanation for these by a long shot.
| roundandround wrote:
| If China lied about its balloons (over Beijing) being from
| the US, would the US attempt to do the impossible and prove
| that something never existed or agree and ask for them
| back?
| coldtea wrote:
| Didn't they?
| moose_man wrote:
| No, the Chinese get aggressive if anyone flies in the South
| China Sea let alone over China proper.
| kurthr wrote:
| Exactly, China was boasting about it's ability to shoot
| down high altitude balloons in 2019. You can still find
| some stuff in Mandarin, but everything in english, has been
| taken down. They were boasting about their high altitude
| surveillance balloons a year ago, and again you can still
| find some original material, but all of the english
| language articles have been removed. The propaganda machine
| is spinning on it's head now.
| hackerlight wrote:
| What would be the purpose of surveillance balloons if not to
| use them on your rivals...
| kQq9oHeAz6wLLS wrote:
| When the citizenry has the ability to remove you from power,
| they become your rivals
| moose_man wrote:
| It is cost benefit trade off. Sure US could get some benefit
| but at the expense of the similar scenario that is playing
| out now here. Using balloons over national territory is
| highly escalatory. Whatever they're getting intelligence wise
| it can't be worth the fallout. Building a capability is not
| the same as employing it. We have nukes and yet we don't
| regularly bring them out.
| nyc_data_geek1 wrote:
| To surveil your population, as most "first world" governments
| seem so keen on?
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