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That’s a problem with NCMEC, not Apple’s proposal today. Furthermore, if it were an actual problem, it would’ve already manifested with the numerous current use

That’s a problem with NCMEC, not Apple’s proposal today. Furthermore, if it were an actual problem, it would’ve already manifested with the numerous current users of PhotoDNA which includes Facebook and Google. I don’t think the database of known CSAM content includes photos that cannot be visually recognized as child abuse.

tsimionescu 5y ago
Why do you not think that? As far as I understand, there is no procedure for reviewing the contents, it is simply a database that law enforcement vouches is full of bad images.
- shuckles 5y ago
  NCMEC, not law enforcement, produces a list of embeddings of known images of child abuse. Facebook and Google run all photos uploaded to their platforms against this list. Those which match are manually reviewed and if confirmed to depict such scenes, are reported to CyberTip. If the list had a ton of false positives, you think they wouldn’t notice that their human reviewers were spending a lot of time looking at pictures of the sky?
  - suizi 5y ago
    It's well-known that this algorithm doesn't have a perfect matching rate. It'd be easy to presume that any false positives are not erroneously tagged images, but the error rate of the underlying algorithm, if all the images were tagged correctly. Who would know? IIRC Wired reported the algorithm "PhotoDNA" worked around 99% of the time a number of years ago, however newer algorithms may be fuzzier. This is not the same algorithm. And even "PhotoDNA" appears to change over time. I doubt reviewers of such content are at a liberty to discuss what they see or don't with anyone here. Standard confidentiality agreements.
cwkoss 5y ago
> it would’ve already manifested How do we know it hasn't? Maybe the people who have seen these situations have received to national security letters that claim to prevent them from even talking to a lawyer about the non-CSAM classified images they've seen in the course of the investigation?

tsimionescu 5y ago

Why do you not think that? As far as I understand, there is no procedure for reviewing the contents, it is simply a database that law enforcement vouches is full of bad images.

shuckles 5y ago
NCMEC, not law enforcement, produces a list of embeddings of known images of child abuse. Facebook and Google run all photos uploaded to their platforms against this list. Those which match are manually reviewed and if confirmed to depict such scenes, are reported to CyberTip. If the list had a ton of false positives, you think they wouldn’t notice that their human reviewers were spending a lot of time looking at pictures of the sky?
- suizi 5y ago
  It's well-known that this algorithm doesn't have a perfect matching rate. It'd be easy to presume that any false positives are not erroneously tagged images, but the error rate of the underlying algorithm, if all the images were tagged correctly. Who would know? IIRC Wired reported the algorithm "PhotoDNA" worked around 99% of the time a number of years ago, however newer algorithms may be fuzzier. This is not the same algorithm. And even "PhotoDNA" appears to change over time. I doubt reviewers of such content are at a liberty to discuss what they see or don't with anyone here. Standard confidentiality agreements.

cwkoss 5y ago

> it would’ve already manifested How do we know it hasn't? Maybe the people who have seen these situations have received to national security letters that claim to prevent them from even talking to a lawyer about the non-CSAM classified images they've seen in the course of the investigation?