this post was submitted on 18 Sep 2024
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[–] [email protected] 22 points 1 month ago* (last edited 1 month ago) (3 children)

looks dubious

The problem here is that if this is unreliable -- and I'm skeptical that Google can produce a system that will work across-the-board -- then you have a synthesized image that now has Google attesting to be non-synthetic.

Maybe they can make it clear that this is a best-effort system, and that they only will flag some of them.

There are a limited number of ways that I'm aware of to detect whether an image is edited.

  • If the image has been previously compressed via lossy compression, there are ways to modify the image to make the difference in artifacts in different points of the image more visible, or -- I'm sure -- statistically look for such artifacts.

  • If an image has been previously indexed by something like Google Images and Google has an index sufficient to permit Google to do fuzzy search for portions of the image, then they can identify an edited image because they can find the original.

  • It's possible to try to identify light sources based on shading and specular in an image, and try to find points of the image that don't match. There are complexities to this; for example, a surface might simply be shaded in such a way that it looks like light is shining on it, like if you have a realistic poster on a wall. For generation rather than photomanipulation, better generative AI systems will also probably tend to make this go away as they improve; it's a flaw in the image.

But none of these is a surefire mechanism.

For AI-generated images, my guess is that there are some other routes.

  • Some images are going to have metadata attached. That's trivial to strip, so not very good if someone is actually trying to fool people.

  • Maybe some generative AIs will try doing digital watermarks. I'm not very bullish on this approach. It's a little harder to remove, but invariably, any kind of lossy compression is at odds with watermarks that aren't very visible. As lossy compression gets better, it either automatically tends to strip watermarks -- because lossy compression tries to remove data that doesn't noticeably alter an image, and watermarks rely on hiding data there -- or watermarks have to visibly alter the image. And that's before people actively developing tools to strip them. And you're never gonna get all the generative AIs out there adding digital watermarks.

  • I don't know what the right terminology is, but my guess is that latent diffusion models try to approach a minimum error for some model during the iteration process. If you have a copy of the model used to generate the image, you can probably measure the error from what the model would predict -- basically, how much one iteration would change an image or part of it. I'd guess that that only works well if you have a copy of the model in question or a model similar to it.

I don't think that any of those are likely surefire mechanisms either.

[–] [email protected] 3 points 1 month ago

The problem here is that if this is unreliable...

And the problem if it is reliable is that everyone becomes dependent on Google to literally define reality.

[–] [email protected] 1 points 1 month ago* (last edited 1 month ago)

Fun fact about AI products (or any gold rush economy) it doesn't have to work. It just has to sell.

I mean this is generally true about anything but it's particularly bad in these situations. Also PT Barnum had a few thoughts on this as well.

[–] [email protected] -2 points 1 month ago (2 children)

I guess this would be a good reason to include some exif data when images are hosted on websites, one of the only ways to tell an image is true from my little understanding.

[–] [email protected] 3 points 1 month ago (1 children)
[–] [email protected] -3 points 1 month ago* (last edited 1 month ago) (1 children)

I guess, but the original image would be somewhere to be scraped by google to compare and see an earlier version. Thats why you don’t just look at the single image, you scrape multiple sites looking for others as well.

Theres obviously very specific use cases that can take advantage of brand new images that are created on a computer, but theres still ways of detecting that with other methods as explained by the user I responded to.

[–] [email protected] 0 points 1 month ago (1 children)

It seems like you’re assuming that file modified times are fixed…? Every piece of metadata like that can be altered. If you took a picture and posted it somewhere, I could take it and alter it to my liking, then add in some fake exif data as well as make it look like I modified the image before your actual original version.

You can’t use any of that metadata to prove anything.

[–] [email protected] 0 points 1 month ago* (last edited 1 month ago) (1 children)

No, but it seems like you’re assuming they would look at this sandboxed by itself…? Of course there is more than one data point to look at, when you uploaded the image would noted, so even if you uploaded an image with older exif data, so what? The original poster would still have the original image, and the original image would have scraped and documented when it was hosted. So you host the image with fake data later, and it compares the two and sees that your fake one was posted 6 months later, it gets flagged like it should. And the original owner can claim authenticity.

Metadata provides a trail and can be used with other data points to show authenticity when a bad actor appears for your image.

You are apparently assuming to be looking at a single images exif data to determine what? Obviously they would use every image that looks similar or matches identical and use exif data to find the real one. As well as other mentioned methods.

The only vector point is newly created images that haven’t been digitally signed, anything digitally signed can be verified as new, unless you go to extreme lengths to fake and image and than somehow recapture it with a digitally signed camera without it being detected fake by other methods….

[–] conciselyverbose 1 points 1 month ago (1 children)

No, the default should be removing everything but maybe the date because of privacy implications.

[–] [email protected] -3 points 1 month ago* (last edited 1 month ago) (1 children)

include some EXIF data

Thats what I said.

Date, device, edited. That can all be included, location doesn’t need to be.

[–] conciselyverbose 3 points 1 month ago (1 children)

The device is no more anyone else's business than anything else.

It should absolutely not be shared by default.

[–] [email protected] -3 points 1 month ago (1 children)

To prove the legibility of the image? It’s a great data point that’s pretty anonymous, they don’t need to include the Mac, sim, serial or other information.

[–] conciselyverbose 0 points 1 month ago (1 children)

A. It's not even the weakest of weak evidence of whether a photo is legitimate. It tells you literally zero.

B. Even if it was concrete proof, that would still be a truly disgusting reason to think you were entitled to that information.

[–] [email protected] -2 points 1 month ago* (last edited 1 month ago) (1 children)

You can use metadata to prove an image is real, you can’t prove something is real without it, so it’s the only current option. It tells you a lot, you just don’t want people to know it apparently, but that doesn’t change it can be used to legitimatize an image.

What’s disgusting about knowing if an image was taken on a Sony dslr, and Android or an iPhone? And entitled…? This is so you can prove your image is real? The hell you talking about here?

[–] conciselyverbose 1 points 1 month ago* (last edited 1 month ago) (1 children)

No, you cannot use metadata as even extremely weak evidence that an image is real. It is less than trivial to fake, and the second anyone even hints at making it a standard approach, it will be on every photo anyone uses to mislead anyone.

Most photos on the internet are camera phones, and you absolutely are not entitled to know what phone someone has. Knowing someone's phone has infinitely more value to fingerprinting a user than including metadata could ever theoretically have to demonstrate whether a photo is legitimate or not.

Photos without a specific, on record provenance from a credible source are no longer useful for evidence of anything. You cannot go back from that.

[–] [email protected] -2 points 1 month ago* (last edited 1 month ago) (1 children)

Meta data creates a string, if you want to claim ownership of an image and I show an image with earlier metadata, who’s is the real one? Yes it can be faked, but it can also be traced. Thats not a reason to not do something, the hell? That’s like suggesting you can’t police murders because someone can fake a murder.

What is identifiable about the type of phone you have…? Anyone that sees you in public has that information lmfao, there’s far more “fingerprintable” data in the exif than the device that anyone can visually see you have….. that’s the strangest privacy angle I’ve seen and you’re talking like it’s this big huge issue? I’ve asked you to explain and you haven’t, why is this?

And without that exif data you can’t prove any of that… you realize this… yeah…?

What is your point here? That you’re concerned that you might have someone knowing your phone? You realize you can scrub that information yourself if you’re not worried about proving authenticity…? Yeah…?

[–] conciselyverbose 2 points 1 month ago (1 children)

You very clearly have no idea whatsoever what you're talking about. This is all complete nonsense.

Anyone can write exif data to say anything they want it to. You "showing an image with earlier metadata" is completely arbitrary and doesn't tell anyone literally anything about which one is more likely to be "real". Again, it's not "weak" or "bad" evidence. It is literally not capable of being evidence.

[–] [email protected] -3 points 1 month ago* (last edited 1 month ago) (1 children)

So you gonna address what’s identifiable about a phone… or are you just gonna ignore this and scream about the one thing we know can prove authenticity of an image? I’ve addressed the can be faked… you gonna address any of my points…?

I said I had a little knowledge, do you have a point here or you just gonna scream that exif data can be faked? I was trying to have a civil conversation about this.

If there’s an image with two different exifs data, this will flag it, problem solved, what’s your issue…? Isn’t that the point? Flag fake images…?

[–] conciselyverbose 1 points 1 month ago (1 children)

What device you use is one of the biggest data points advertisers and trackers use to fingerprint you across the internet. No, "I use a Google Pixel 9" does not, by itself, de-anonymize you, but it does make a big dent when combined with other information.

You keep talking about "proving the authenticity of an image" with something that does not even move you .00000001% towards an image being legitimate. It is literally zero information about that question in every possible context. It is, eventually, if you throw out every camera on the planet and use heavy cryptography, theoretically possible to eventually, in the future, provide some evidence that some future picture came from some specific camera, but it will still not be proof that what that camera processed wasn't manipulated.

[–] [email protected] -3 points 1 month ago* (last edited 1 month ago) (1 children)

….

https://arstechnica.com/information-technology/2024/09/google-seeks-authenticity-in-the-age-of-ai-with-new-content-labeling-system/

Its literally the method that’s used…

group of tech companies created the C2PA system beginning in 2019 in an attempt to combat misleading, realistic synthetic media online. As AI-generated content becomes more prevalent and realistic, experts have worried that it may be difficult for users to determine the authenticity of images they encounter. The C2PA standard creates a digital trail for content, backed by an online signing authority, that includes metadata information about where images originate and how they've been modifie

For 5 fucking years already….

Okay, what does an image metadata and advertising have to do with each other…? I’m not here for conspiracy theories, I’m here to have a discussion, which you clearly can’t do.

You claim I don’t know much… I stated as much… yet you don’t know how images are verified …? The fuck…? Go off on whatever tangent you want, but exit data is the only way to determine if a photo is legitimate… yes it can be faked… congrats for pointing that out and only that this entire time… even though I already mentioned that…

What’s your point dude? Seriously I’m blocking you if you can’t have a discussion. Proof of ownership and detecting fakes are two mutually inclusive things, they can both be used to help the others legitimacy, why are you only looking at this from one angle here? Exif is for ownership, the methods in the comment I responded to are for other things. I mentioned THIS previously as well….

[–] conciselyverbose 1 points 1 month ago (1 children)

You realize that your article says it's a pipe dream right? Because even Google, pushing it, has no interest in actually supporting it in its tools, and neither does anyone else?

Advertising tracking is the primary space your privacy is invaded online. The fact that what phone you use is one of the most valuable data points they have that isn't "you actively being signed in somewhere that shares it" is the evidence that telling people what phone you have to share a photo is a massive privacy issue. Because what phone you have is a lot of information.