Oh. I didn’t know that. I don’t use Apple products and just read the news, I must have missed how the story turned out, so thanks for the info.
Technically I suppose it doesn’t make a huge difference. It still gets scanned by Apple software. And sent to them if it’s deemed conspicuous. And the algorithm on a device is probably limited by processing power and energy budget. So it might even be less accurate. But this is just my speculation. I think all of that is more of a marketing stunt. This way the provider reduces cost, they don’t need additional servers to filter the messages and in the end it doesn’t really matter where exactly the content is processed if it’s a continuous chain like in the Apple ecosystem.
The last story I linked about the dad being incriminated for sending the doctor a picture would play out the same way, regardless.
Edit: I googled it and it seems the story with Apple has changed multiple times. The last article I read says they don’t even do on-device scanning. Just a ‘nude filter’. Whatever that is. I’m cautious around cloud services anyways. And all of that might change and also affect old pictures. We just avoided mandatory content filtering in the EU and upload filters and things like that are debated regularly. Also the US has updated their laws regarding internet crime and prevention of child exploitation in the last years. I’m generally unsure where we’re headed with this.
The proposal was only for photos stored on iCloud. Apple has a legitimate interest in not wanting to actually host abuse material on their servers. The plan was also calibrated for one in one trillion false positives (it would require multiple matches before an account could be flagged), followed by a manual review by an employee before reporting to authorities. It was so very carefully designed.
Do you happen to know a good source for information on this? I don’t want to highjack this discission, since it’s not that closely related to the original subject… But I’d be interested in more technical information. Most news articles seem to be a bit biased and I get it, both privacy and protection of children are sensible topics and there are feelings envolved.
One in a trillion sounds like a probability of a hash collision. So that would be just checking if they already have the specific image in their database. It’ll trigger if someone downloaded an already existing image and not detect new images taken with a camera. I’m somewhat fine with that.
And I was under the impression that iPhones connected to the iCloud sync the pictures per default? So “only for photos stored on iCloud” would practically mean every image you take, unless you deliberately changed the settings on your iPhone?
Do you happen to know a good source for information on this?
Apple released detailed whitepapers and information about it when originally proposed but they shelved it so I don’t think they’re still readily available.
One in a trillion sounds like a probability of a hash collision.
Basically yes, but they’re assuming a much greater likelihood of a single hash collision. The system would upload a receipt of the on-device scan along with each photo. A threshold number of matches would be set to achieve the one in a trillion confidence level. I believe the initial estimate was roughly 30 images. In other words, you’d need to be uploading literally dozens of CSAM images for your account to get flagged. And these accompanying receipts use advanced cryptography so it’s not like they’re seeing “oh this account has 5 potential matches and this one has 10”; anything below the threshold would have zero flags. Only when enough “bad” receipts showed up for the same account would they collectively flag it.
And I was under the impression that iPhones connected to the iCloud sync the pictures per default?
This is for people who use iCloud Photo Library, which you have to turn on.
