Cornell Researchers Develop Invisible Light-Based Watermark To Detect Deepfakes
- Reference: 0178658408
- News link: https://slashdot.org/story/25/08/12/2214243/cornell-researchers-develop-invisible-light-based-watermark-to-detect-deepfakes
- Source link:
> Programmable light sources such as computer monitors, studio lighting, or certain LED fixtures can be embedded with coded brightness patterns using software alone. Standard non-programmable lamps can be adapted by fitting them with a compact chip -- roughly the size of a postage stamp -- that subtly fluctuates light intensity according to a secret code. The embedded code consists of tiny variations in lighting frequency and brightness that are imperceptible to the naked eye. Michael explained that these fluctuations are designed based on human visual perception research. Each light's unique code effectively produces a low-resolution, time-stamped record of the scene under slightly different lighting conditions. [Abe Davis, an assistant professor] refers to these as code videos.
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> "When someone manipulates a video, the manipulated parts start to contradict what we see in these code videos," Davis said. "And if someone tries to generate fake video with AI, the resulting code videos just look like random variations." By comparing the coded patterns against the suspect footage, analysts can detect missing sequences, inserted objects, or altered scenes. For example, content removed from an interview would appear as visual gaps in the recovered code video, while fabricated elements would often show up as solid black areas. The researchers have demonstrated the use of up to three independent lighting codes within the same scene. This layering increases the complexity of the watermark and raises the difficulty for potential forgers, who would have to replicate multiple synchronized code videos that all match the visible footage.
The concept is called [2]noise-coded illumination and was presented on August 10 at SIGGRAPH 2025 in Vancouver, British Columbia.
[1] https://www.techspot.com/news/109028-researchers-develop-invisible-light-based-watermark-detect-deepfakes.html
[2] https://news.cornell.edu/stories/2025/07/hiding-secret-codes-light-protects-against-fake-videos
What Orwell got wrong (Score:2)
I reread 1984 a few years ago and the thing that really struck me is what Orwell got wrong: the notion that you need to erase evidence of factual data (at great effort/expense) in order to propagate lies. It turns out that you just need to shout a little louder and a lot of folks will eat it up.
Which should have been obvious by then, but which was not even obvious to me when I read it the first time (in HS - around '84). But at this point we've all very much lived through it (and continue to).
The number o
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I read 1984 in 1984 myself :-), it seemed like an interesting thing to do. I think we all knew from the 1930's Germany that repeating lies over and over again makes it true in some peoples mind. Trolls get some kind of joy, I think, in repeating lies. Simply pointing them to a fact check does not seem to matter. That is what this technology does, it points them to a fact check, but I don't think it will matter much. The Nancy Pelozi video where she looked drunk went viral, and all MAGAs seem to rep
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> what Orwell got wrong: the notion that you need to erase evidence of factual data (at great effort/expense) in order to propagate lies
No, he didn't. That, as was made patently clear by the long and tedious dialogs between O'Brien and Smith in the torture room, was a temporary measure while people were trained to deny reality. There was even the break-through scene, really visual:
"'How many fingers do you see, kwerle?' asked the ICE agent gently. And this time, for the first time kwerle saw with clarity two fingers raised" or somesuch.
He even got right the bit that even if social pressure and fake news will do it without the need of physic
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off topic, but that reminds me of when Picard was captured by the Cardassians and was tortured in Star Trek TNG. I never linked it to the book 1984 before.
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> I reread 1984 a few years ago and the thing that really struck me is what Orwell got wrong: the notion that you need to erase evidence of factual data (at great effort/expense) in order to propagate lies. It turns out that you just need to shout a little louder and a lot of folks will eat it up.
That was a time when "photoshop" meant an actual workshop with lenses, cameras, artists, photographers, and so much else that only a government or the exceedingly wealthy could afford. I saw a YouTube video recently on how wealthy women in the days of black and white photography would spend good money to have photos of themselves taken and manipulated to show them as having unnaturally thin waists or whatever was fashionable. Even then they'd take steps to simplify the process by having a blank background
"roughly the size of a postage stamp" (Score:1)
What's a postage stamp?
I'm only half joking as I know what a postage stamp looks like but I'm not sure I put a postage stamp on anything in the last decade. I've sent things in the mail but it's been either in a prepaid envelope or I took something to the post office where they did whatever to indicate postage paid on it. At least they didn't give this in Libraries of Congress, or football fields. If the press is going to use such size comparisons then perhaps they could use something more relatable to t
Ok so the same as power line analysis (Score:2)
So the same way the gov tracks the location of videos. Recorded ac power fluctuations from all power plants detected from small lighting changes in the tracked video.
I seen this on a documentary years ago. Not new.
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I was kind of "yawn" at the thought that this is new nor original, so I started talking about... ok.. this is fake. what now? a portion of the population doesn't seem to care.
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> So the same way the gov tracks the location of videos. Recorded ac power fluctuations from all power plants detected from small lighting changes in the tracked video.
> I seen this on a documentary years ago. Not new.
I'm curious, can someone fill me in on more? I'd like to know more on how and when such techniques were used.
I do recall hearing how secure facilities would break the connection to the electric grid with a motor-generator set. This was to prevent anyone on the outside from picking up signals from the inside on the wires. The idea was that the mass of the spinning motor-generator was a kind of low pass filter that would stop any attempts to pick up data over the wires. Now I see that this works both ways
Researchers don't understand (Score:1)
So entire videos are now being deepfaked. Somehow, they think that noise encoding won't be deepfaked along with it? Strange. Almost as if the researchers don't understand what a deepfake is.
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Personally, I just use common sense to know if a video is deepfaked. I know that almost everything on Bitchute is fake, and almost everything on a credible news source is credible (after checking a few other sources). There does seem to be a disturbingly large percentage of Americans who seem to have let their brains fall out when they tilt their head.
yes but... (Score:2)
will senator Vreenak be able to tell if it's a fake?
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I looked up the reference to that... seems like a good reference: Upon examination of the data rod, however, Vreenak discovered that the evidence was forged, and headed back to Romulus threatening to expose the plot. However, due to sabotage by Garak, Vreenak's shuttle exploded while en route, killing the senator, and at least two of his guards. The subsequent investigation by the Tal Shiar uncovered the fabricated evidence, but its defects appeared to be the result of the explosion. The Romulans logically
This is great and all.. (Score:3)
And it makes common sense. The problem is that there is a percentage of people who like to be lied to, and who will deny a video was manipulated, or won't care.