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Apple plans to scan US iPhones for child abuse imagery

ft.com

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Re: Apple plans to scan US iPhones for child abuse imagery

#341

Post by Retric »

runjake wrote: post #326
Retric wrote: post #172

Earlier quoted context omitted.

There is zero AI classification involved, it’s a lookup vs hashes of known child porn images. You would need a hash collision, misidentified photo in the dataset, or legitimate use case to end up with a false positive.

You are wrong. It's AI. Citation: https://www.apple.com/child-safety/pdf/CSAM_Detection_Techni...

It’s perceptual hashing not AI classification. “NeuralHash is a perceptual hashing function that maps images to numbers.”

The perceptual hashing is based on AI techniques. “The system computes these hashes by using an embedding network to produce image descriptors and then converting those descriptors to integers using a Hyperplane LSH (Locality Sensitivity Hashing) process.”

The difference is AI classification is based on defining something as say a “Cat” and then the AI spits some association with how cat like the image is. This extracts features from an image then compares lists of features to specific images.

Re: Apple plans to scan US iPhones for child abuse imagery

#342

Post by cududa »

jtbayly wrote: post #226
Retric wrote: post #172

Earlier quoted context omitted.

There is zero AI classification involved, it’s a lookup vs hashes of known child porn images. You would need a hash collision, misidentified photo in the dataset, or legitimate use case to end up with a false positive.

Zero AI involved? Simple hashes? Source needed. From what I read, you are making false claims.

The PhotoDNA platform doesn’t offer the participating organization raw photos, just hashes. The AI part is stitching photos with matching edges together, incase someone cropped them into different parts.

Again, Apple nor any company, have access to the source data, just hashes.

Re: Apple plans to scan US iPhones for child abuse imagery

#343

Post by [deleted] »

devwastaken wrote: post #122

Reminder that even accusations of abuse imagery will get you in cuffs and your children taken away (see article at the end) Linux truly is the last bastion of sanity. I am so glad that linux desktops took off and work as well as they do. Last thing I should be worrying about is if an employee at Microsoft or Apple decides their "automated system with no errors" decides that a hash collision or a picture of a baby is…

[deleted]

Re: Apple plans to scan US iPhones for child abuse imagery

#344

Post by cududa »

GeekyBear wrote: post #337
partiallypro wrote: post #289

Earlier quoted context omitted.

Again, that is not the same as scanning a local machine for it. That is all things that are on Microsoft's own servers or in their search results. Microsoft, Google, Cloudflare all have features like this. It's not the same as scanning local machines.

Again, the Windows 10 TOS extended that to scanning the local machine as well.

When you download an app it compares hashes locally to source material published hash. This is absolutely no different

Re: Apple plans to scan US iPhones for child abuse imagery

#345

Post by cududa »

tyingq wrote: post #294
heavyset_go wrote: post #265

Earlier quoted context omitted.

They aren't using file hashes like SHA1, but perceptual hashes and then a fuzzy metric like hamming distance to make a fuzzy match. It's entirely possible for two images that have nothing to do with each other to have similar hashes.

Yes, that's what I was alluding to. It's a perceptual hash, so you could probably take a flagged image and superficially alter it (contrast/color/crop/whatever) until it wasn't anything visually objectionable on it's own. But it would still match the perceptual hash.

The poor souls that do the work of entering the images into the database select identification blocks, not showing the victim (a lamp, wall paper, etc), that reviewers on the “client” side check against

Re: Apple plans to scan US iPhones for child abuse imagery

#346

Post by runjake »

Retric wrote: post #341
runjake wrote: post #326

Earlier quoted context omitted.

You are wrong. It's AI. Citation: https://www.apple.com/child-safety/pdf/CSAM_Detection_Techni...

It’s perceptual hashing not AI classification. “NeuralHash is a perceptual hashing function that maps images to numbers.” The perceptual hashing is based on AI techniques. “The system computes these hashes by using an embedding network to produce image descriptors and then converting those descriptors to integers using a Hyperplane LSH (Locality Sensitivity Hashing) process.” The difference is AI classification is ba…

It sure sounds a lot like AI to me. Saying its just hashes seems misleading to me.

From the PDF:

"The system generates NeuralHash in two steps. First, an image is passed into a convolutional neural network to generate an N-dimensional, floating-point descriptor. Second, the descriptor is passed through a hashing scheme to convert the N floating-point numbers to M bits. Here, M is much smaller than the number of bits needed to represent the N floating-point numbers. NeuralHash achieves this level of compression and preserves sufficient information about the image so that matches and lookups on image sets are still successful, and the compression meets the storage and transmission requirements.

The neural network that generates the descriptor is trained through a self-supervised training scheme. Images are perturbed with transformations that keep them perceptually identical to the original, creating an original/perturbed pair. The neural network is taught to generate descriptors that are close to one another for the original/perturbed pair. Similarly, the network is also taught to generate descriptors that are farther away from one another for an original/distractor pair. A distractor is any image that is not considered identical to the original. "

Re: Apple plans to scan US iPhones for child abuse imagery

#347

Post by Retric »

diebeforei485 wrote: post #229
Retric wrote: post #172

Earlier quoted context omitted.

There is zero AI classification involved, it’s a lookup vs hashes of known child porn images. You would need a hash collision, misidentified photo in the dataset, or legitimate use case to end up with a false positive.

The article says that Apple calls this system neuralMatch. I'm not sure why that name gives you confidence that there is zero AI involved?

They are using AI techniques as part of perceptual hashing. In other words it’s trying to match files with specific images rather than abstract concepts.

Re: Apple plans to scan US iPhones for child abuse imagery

#348

Post by syshum »

lstamour wrote: post #53
syshum wrote: post #34

Earlier quoted context omitted.

Plain file hashing for this kind of thing has not been used for years (or even decades), Microsoft came out with Photo DNA along time ago, and I am sure now days they have something ML powered to do it. I am not sure the accuracy of these systems but even if they are pretty accurate there is something off putting about this trend. This very much feels like a Guilty until proven innocent type of program... "if you hav…

> Guilty until proven innocent type of program But this software doesn’t make arrests? A comparison would be police asking for what cellphones were in an area. There should be a lot of due process that happens before anything comes of this. I imagine police won’t look into one photo, they would want to match more than one. I agree though, the scary part might be how to clear your name after an overreaction occurs, si…

So are you in Favor of installing Camera's in every room in your home, that you do not control, and that the police and review anytime?

If in the US Do you like the concept behind 4th amendment? being free from unreasonable searches unless probable cause can be articulated that you have committed a crime?

It is very scary how effect the "think of the children" narrative is to get people to willing give up their liberty

Re: Apple plans to scan US iPhones for child abuse imagery

#349

Post by smsm42 »

So, how long before the same technology is used to fight "misinformation" and "domestic terrorism" (e.g. memes that disagree with official point of view)? How long until it's used to ban "hateful speech", or any speech unapproved by the gov^H^H^HReal Government - the Almighty Apple?

Re: Apple plans to scan US iPhones for child abuse imagery

#350

Post by smsm42 »

Crontab wrote: post #150
imroot wrote: post #3

https://towardsdatascience.com/black-box-attacks-on-perceptu... I mean, who's to say that my hash is actually what they think it is... ...and if it's not uploaded to iCloud for someone to manually review what the image is, is that going to be enough to get a search warrant for my phone? "AUSA SOMEONE: But, Your Honor, The Defendant's phone has an image that matched a hash of a CSAM picture!" "DEFENDANT: I'm not going…

I have always been concerned that this system could be weaponized as a way gain access to someone's account. For example: - Add the hash of a non-pornographic image to the database - Using a burner email address, email the non-pornographic image to the target's Gmail address. The target wouldn't think anything of it. - The innocent image would trigger a CP alert, giving law enforcement the pretense it needs to access…

This is how the police gets warrantless searches "for drugs" - having identified the subject, call for a dog and have it "alert" on the subject (or the vehicle belonging to the subject), after which there's a probable cause for a search and everything that is found can be used against the subject. The fact that there was no drugs is irrelevant.

Now let's translate it to digital world and eliminate the non-scalable components - and you get AI "alerting" on the content of your account and it's a probable cause for searching you.

But the best part is of course the Apple doesn't even need a probable cause to search you - they aren't the police, so they are free to search anything at their pleasure and then report to the police. And this report, by itself, would be the probable cause, of course.

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