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Check if a file was made with Claude

claude.com

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Re: Check if a file was made with Claude

#91

Post by Retr0id »

panarky wrote: post #89
Retr0id wrote: post #68

Earlier quoted context omitted.

Camera C2PA can never meaningfully confirm that a photo is authentic, it bears about as much credence as EXIF metadata. It's like saying the existence of DRM confirms that a movie hasn't been pirated.

C2PA cryptographically guarantees that the bytes came from a hardware/software signer and that the signed payload has not been modified since that signature was applied. So no, C2PA is not as easy to spoof as EXIF. And no, the existence of DRM doesn't validate the integrity or the provenance of the bytes.

And what happens when someone tells the hardware signer to sign the bytes of a fake image?

What happens when someone extracts the signing key?

The presence of cryptography doesn't magically make something trustworthy.

Re: Check if a file was made with Claude

#92

Post by _--__--__ »

fph wrote: post #85
coffeecoders wrote: post #46

What is interesting to me is that stripping the C2PA data is easy, but faking it is hard. You can resave the file and the "made with Claude" signal disappears, but you cannot make a random file pass as Claude-made without Anthropic's signing key. So the useful guarantee is one-way. No signature means almost nothing.

And it's one-way in the direction that typically no one cares about.

Anthropic's legal team cares

Re: Check if a file was made with Claude

#95

Post by HoldOnAMinute »

aero-glide2 wrote: post #67
hughw wrote: post #65

Earlier quoted context omitted.

Or just write a 6 line program to remove the metainfo from the file?

very difficult to remove text watermarking

There must be some set of outputs that is completely resistant to watermarking. For example if I told Claude to output "Hello, World"

Re: Check if a file was made with Claude

#96

Post by panarky »

Retr0id wrote: post #91
panarky wrote: post #89

Earlier quoted context omitted.

C2PA cryptographically guarantees that the bytes came from a hardware/software signer and that the signed payload has not been modified since that signature was applied. So no, C2PA is not as easy to spoof as EXIF. And no, the existence of DRM doesn't validate the integrity or the provenance of the bytes.

And what happens when someone tells the hardware signer to sign the bytes of a fake image? What happens when someone extracts the signing key? The presence of cryptography doesn't magically make something trustworthy.

Just because you can imagine how a thing could theoretically be broken does not make it broken.

It's like saying a prisoner has the same freedoms as everyone else because he could theoretically escape.

Re: Check if a file was made with Claude

#97

Post by huhtenberg »

For anyone wondering who the text watermarking works:

  Instead of using an arbitrary random number generator
  to pick the next word, watermarking uses a secret key
  and a few words that come before to settle what
  word the model should pick.
https://www.anthropic.com/news/claude-text-watermark

* Edited the above from initially asking if anyone has any ideas how it works. Found the answer, rewrote the comment.

Re: Check if a file was made with Claude

#98

Post by dgellow »

pixl97 wrote: post #63
dgellow wrote: post #43

> Knowing where content came from, and whether AI was involved, makes it easier to trust what you see online. That’s a cute way to imply their service is used to generate misinformation. They are basically saying to not trust the AI content made from their own product :)

I mean, if we're developing an AGI do you expect it not to be able to generate misinformation?

I have no idea how you’re reading that from my comment

Re: Check if a file was made with Claude

#99

Post by lanyard-textile »

panarky wrote: post #96
Retr0id wrote: post #91

Earlier quoted context omitted.

And what happens when someone tells the hardware signer to sign the bytes of a fake image? What happens when someone extracts the signing key? The presence of cryptography doesn't magically make something trustworthy.

Just because you can imagine how a thing could theoretically be broken does not make it broken. It's like saying a prisoner has the same freedoms as everyone else because he could theoretically escape.

It's not an apt analogy. The prisoner's every move is guarded; the camera is free in your hands to be disassembled.

Re: Check if a file was made with Claude

#100

Post by bilalq »

mhitza wrote: post #33
Tiberium wrote: post #5

This is just C2PA for Claude-processed files, apparently. It's not related to their text watermarking. C2PA is file metadata and can be trivially stripped away, unlike hidden watermarks, e.g. SynthID.

That is where their responsibility ends in terms of the EU AI Act. And that is fine and how it should be, no secret watermarks.

There's no way text watermarking isn't causing a degradation in writing quality.
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