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The Problem with Perceptual Hashes

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Re: The Problem with Perceptual Hashes

#81

Post by seph-reed »

marcinzm wrote: post #27

Given all the zero day exploits on iOS I wonder if it's now going to be viable to hack someone's phone and upload child porn to their account. Apple with happily flag the photos and then, likely, get those people arrested. Now they have to, in practice, prove they were hacked which might be impossible. Will either ruin their reputation or put them in jail for a long time. Given past witch hunts it could be decades be…

Someone is going to figure out how to make false positives, and then an entire genre of meme will be born from putting regular memes through a false positive machine, just for the lulz.

Someone else could find a way to make every single possible mutation of false positive Goatse/Lemonparty/TubGirl/etc. Then some poor Apple employee has to check those out.

Re: The Problem with Perceptual Hashes

#82

Post by KarlKemp »

yellow_lead wrote: post #61

Regarding false positives re:Apple, the Ars Technica article claims > Apple offers technical details, claims 1-in-1 trillion chance of false positives. There are two ways to read this, but I'm assuming it means, for each scan, there is a 1-in-1 trillion chance of a false positive. Apple has over 1 billion devices. Assuming ten scans per device per day, you would reach one trillion scans in ~100 days. Okay, but not al…

Do you really believe that if they scan your photo library at 10am and don't get any false positives, another scan five hours later, with no changes to the library, has the same chance of getting false positives as the first one, independent of that result?

Re: The Problem with Perceptual Hashes

#83

Post by brian_herman »

Fortunately I have a cisco router and enough knowledge to block the 17.0.0.0/8 ip address range. This combined with an openvpn vpn will block all apple services from my devices. So basically my internet will look like this:

Internet CISCO ASUS ROUTER with openvpn Network The cisco router will block the 17.0.0.0/8 ip address range and I will use spotify on all my computers.

Re: The Problem with Perceptual Hashes

#84

Post by slapfrog »

zxcvbn4038 wrote: post #54
stickfigure wrote: post #10

I've also implemented perceptual hashing algorithms for use in the real world. Article is correct, there really is no way to eliminate false positives while still catching minor changes (say, resizing, cropping, or watermarking). I'm sure I'm not the only person with naked pictures of my wife. Do you really want a false positive to result in your intimate moments getting shared around some outsourced boiler room for…

Rookie mistake. Three rules to live by: 1) Always pay your taxes 2) Don’t talk to the police 3) Don’t take photographs with your clothes off

> 2) Don’t talk to the police

2b) Don't buy phones that talk to the police.

Re: The Problem with Perceptual Hashes

#86

Post by brian_herman »

brian_herman wrote: post #83

Fortunately I have a cisco router and enough knowledge to block the 17.0.0.0/8 ip address range. This combined with an openvpn vpn will block all apple services from my devices. So basically my internet will look like this: Internet CISCO ASUS ROUTER with openvpn Network The cisco router will block the 17.0.0.0/8 ip address range and I will use spotify on all my computers.

Disregard comment I don't want to edit it because I am lazy. You can do all of this inside the asus router underneath the routes page just put this inside the asus router: Ip address 17.0.0.0 Subnet 255.0.0.0 Destination 127.0.0.1

Re: The Problem with Perceptual Hashes

#87

Post by TchoBeer »

vineyardmike wrote: post #29
stickfigure wrote: post #10

I've also implemented perceptual hashing algorithms for use in the real world. Article is correct, there really is no way to eliminate false positives while still catching minor changes (say, resizing, cropping, or watermarking). I'm sure I'm not the only person with naked pictures of my wife. Do you really want a false positive to result in your intimate moments getting shared around some outsourced boiler room for…

> Do you really want a false positive to result in your intimate moments getting shared around some outsourced boiler room for laughs? these people also have no incentive to find you innocent for innocent photos. If they err on the side of false-negative, they might find themselves at the wrong end of a criminal search ("why didn't you catch this"), but if they false-positive they at worse ruin a random person's life…

Does claiming a false positive not run the risk of libel?

Re: The Problem with Perceptual Hashes

#88

Post by mattnewton »

jdavis703 wrote: post #60
vineyardmike wrote: post #29

Earlier quoted context omitted.

> Do you really want a false positive to result in your intimate moments getting shared around some outsourced boiler room for laughs? these people also have no incentive to find you innocent for innocent photos. If they err on the side of false-negative, they might find themselves at the wrong end of a criminal search ("why didn't you catch this"), but if they false-positive they at worse ruin a random person's life…

Even still this has to go to the FBI or other law enforcement agency, then it’s passed on to a prosecutor and finally a jury will evaluate. I have a tough time believing that false positives would slip through that many layers. That isn’t to say CASM scanning or any other type of drag net is OK. But I’m not concerned about a perceptual hash ruining someone’s life, just like I’m not concerned about a botched millimete…

By the time it has reached a jury you're already publicly accused of having CSAM which is a life ruining moment on its own, and no one before the jury has much incentive to halt the process on your behalf.

Re: The Problem with Perceptual Hashes

#89

Post by vineyardmike »

TchoBeer wrote: post #87
vineyardmike wrote: post #29

Earlier quoted context omitted.

> Do you really want a false positive to result in your intimate moments getting shared around some outsourced boiler room for laughs? these people also have no incentive to find you innocent for innocent photos. If they err on the side of false-negative, they might find themselves at the wrong end of a criminal search ("why didn't you catch this"), but if they false-positive they at worse ruin a random person's life…

Does claiming a false positive not run the risk of libel?

IANAL but i doubt it - they just forward to law enforcement

Re: The Problem with Perceptual Hashes

#90

Post by iratewizard »

x-shadowban wrote: post #79
iratewizard wrote: post #55

Earlier quoted context omitted.

I don't even have nude photos of my wife. The only person who might would be the NSA contractor assigned to watch her.

what function does the word "even" perform in this sentence?

It's used to emphasize the concept that if anyone would have nudes of my wife, it would be me, her husband. Here's another example of "even" used as an emphasizing word.

>I don't know how to answer that.

>Even I don't know how to answer that.

Hope that helps you with your ESL tests!

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