4 ms·

I was talking with my roommate about this yesterday. Similarly to how in the article there was a cat picture that the NN said was guac, I wonder if we will star

I was talking with my roommate about this yesterday. Similarly to how in the article there was a cat picture that the NN said was guac, I wonder if we will start to see the rise of "booby trapped images" where you might be downloading a wallpaper but unknown to you, that image contains CSAM hashes.

treis 5y ago
Hash collisions are theoretically impossible. It's a completely different issue than a NN misclassifying an image. It reflects poorly on the author that they made this argument.
- jpablo 5y ago
  I'm sorry, but this is 100% incorrect. In fact the opposite is true. Hash collisions are 100% impossible to avoid. You are mapping an infinite set (the set of all possible images) to a finite set (a fixed length number). Cryptographic hashes are designed so that collisions are hard to construct at will. But this is not a cryptographic hash at all and I wouldn't be surprised that constructing an image that matches a given hash is easy.
  - treis 5y ago
    >I'm sorry, but this is 100% incorrect. In fact the opposite is true. >Hash collisions are 100% impossible to avoid. You are mapping an infinite set (the set of all possible images) to a finite set (a fixed length number). If you want to be needlessly pedantic I guess. But for 99.999999% of usage hash collisions don't exist in practice. >Cryptographic hashes are designed so that collisions are hard to construct at will. But this is not a cryptographic hash at all and I wouldn't be surprised that constructing an image that matches a given hash is easy. You got a cite to back this up? Because they claim otherwise.
    - gnulinux 5y ago
      > If you want to be needlessly pedantic I guess. But for 99.999999% of usage hash collisions don't exist in practice. Oh right, that very soothing. The very device I spent $1000 on has 0.0001% of ruining my life by causing a no-knock raid due to a false positive. They should put this stuff on their ads, makes me wanna buy more Apple products. I'd much rather sell all my current Apple devices and permanently switch to linux than do this.
      - deleted 5y ago
        [deleted]
      - treis 5y ago
        No, it's one of the 99.999999% of times where there's 0 risk.
        gnulinux 5y ago
        I'm pointing out that it is technologically possible to do so, and I do not want to bet my life that Apple's code has no bugs. I've been writing code for 20 years, no one can convince me this shit won't ruin at least one life in the next decade after its release.
      - marcus_holmes 5y ago
        There are probably a billion Apple devices out there [0]. Each of those devices has at least a couple hundred unique images on it [1]. If you're correct, and the chance of a hash collision is 0.0001% then for each hash in the database, that's 200,000 collisions. Assuming the database has 1,000 hashes [2] and there's no overlap in collisions for any given person, that 200 million peoples' lives ruined. [0] rough guess based on: https://www.statista.com/statistics/276306/global-apple-iphone-sales-since-fiscal-year-2007/ https://www.statista.com/statistics/276306/global-apple-ipho... the exact number might be off but I think the order of magnitude is about right. [1] My gf has taken at least 3 photos every day for the last 5 years at least (so well over 5000 unique photos) - 200 is very conservative. [2] Again, very conservative. This is a collection of all known child porn images. I wouldn't be surprised if the number is actually two orders of magnitude higher. [edit] replied to the wrong comment. Bugger. Hopefully contributed to the conversation anyway.
- YeBanKo 5y ago
  If you are talking about cryptographic hashes, then yes. But perceptual hashes are design to be similar if the images are similar. I still have to read the tech paper, but most likely it uses some sort of perceptual hashing or AI recognition.

treis 5y ago

Hash collisions are theoretically impossible. It's a completely different issue than a NN misclassifying an image. It reflects poorly on the author that they made this argument.

jpablo 5y ago
I'm sorry, but this is 100% incorrect. In fact the opposite is true. Hash collisions are 100% impossible to avoid. You are mapping an infinite set (the set of all possible images) to a finite set (a fixed length number). Cryptographic hashes are designed so that collisions are hard to construct at will. But this is not a cryptographic hash at all and I wouldn't be surprised that constructing an image that matches a given hash is easy.
- treis 5y ago
  >I'm sorry, but this is 100% incorrect. In fact the opposite is true. >Hash collisions are 100% impossible to avoid. You are mapping an infinite set (the set of all possible images) to a finite set (a fixed length number). If you want to be needlessly pedantic I guess. But for 99.999999% of usage hash collisions don't exist in practice. >Cryptographic hashes are designed so that collisions are hard to construct at will. But this is not a cryptographic hash at all and I wouldn't be surprised that constructing an image that matches a given hash is easy. You got a cite to back this up? Because they claim otherwise.
  - gnulinux 5y ago
    > If you want to be needlessly pedantic I guess. But for 99.999999% of usage hash collisions don't exist in practice. Oh right, that very soothing. The very device I spent $1000 on has 0.0001% of ruining my life by causing a no-knock raid due to a false positive. They should put this stuff on their ads, makes me wanna buy more Apple products. I'd much rather sell all my current Apple devices and permanently switch to linux than do this.
    - deleted 5y ago
      [deleted]
    - treis 5y ago
      No, it's one of the 99.999999% of times where there's 0 risk.
      - gnulinux 5y ago
        I'm pointing out that it is technologically possible to do so, and I do not want to bet my life that Apple's code has no bugs. I've been writing code for 20 years, no one can convince me this shit won't ruin at least one life in the next decade after its release.
    - marcus_holmes 5y ago
      There are probably a billion Apple devices out there [0]. Each of those devices has at least a couple hundred unique images on it [1]. If you're correct, and the chance of a hash collision is 0.0001% then for each hash in the database, that's 200,000 collisions. Assuming the database has 1,000 hashes [2] and there's no overlap in collisions for any given person, that 200 million peoples' lives ruined. [0] rough guess based on: https://www.statista.com/statistics/276306/global-apple-iphone-sales-since-fiscal-year-2007/ https://www.statista.com/statistics/276306/global-apple-ipho... the exact number might be off but I think the order of magnitude is about right. [1] My gf has taken at least 3 photos every day for the last 5 years at least (so well over 5000 unique photos) - 200 is very conservative. [2] Again, very conservative. This is a collection of all known child porn images. I wouldn't be surprised if the number is actually two orders of magnitude higher. [edit] replied to the wrong comment. Bugger. Hopefully contributed to the conversation anyway.
YeBanKo 5y ago
If you are talking about cryptographic hashes, then yes. But perceptual hashes are design to be similar if the images are similar. I still have to read the tech paper, but most likely it uses some sort of perceptual hashing or AI recognition.