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Ghost Font: A font that humans can read but AI cannot

mixfont.com

121–130 of 188 posts

Re: Ghost Font: A font that humans can read but AI cannot

#121
To mitigate the LLM's learning how to decode the Ghost Font perhaps it could change each time for each client in a way that makes learning difficult to adapt to. Variable noise, variable directions, variable angles, variable blur, variable colors, variable pixel sizes. Seed the variability with the first two octets or hextets of their IP and the time of day to increase difficulty in learning through brute force. assuming this will not mess with people that have sensitivity to seizure inducing patterns.

Out of curiosity can any of the LLM's:

- reach this [1] directly

- and decode it?

If so, which LLM's can reach it and which ones can decode it? It's just a static HTML file, nothing fancy. If any of them can reach it directly then I have homework to do. Created using:

    echo -en '\nA I\n\nT e s t\n\n' | toilet --metal -f pagga --html | brotli --best -fncv > /dev/shm/test.html.br
[1] - https://nochan.net/test.html

Re: Ghost Font: A font that humans can read but AI cannot

#122
post #99

GPT-5.6 had no problem seeing the text when giving it a video recording of it. "No problem" as in using temporal analysis with optical flow and vertical-displacement maps to estimate how the image moved, and combine those into a motion map with increased contrast to see the text. I didn't give it any instructions though, just asked it what it said.

I threw it at Fable with the prompt "What does the message say?" and it also figured out without issue. Thought process is interesting https://imgur.com/a/GToXs6W

That's the decoy message, "written in ghost font".

Re: Ghost Font: A font that humans can read but AI cannot

#123

Took me a long time to realise that "Written In Ghost Text" wasn't actually the text I was meant to be reading, and that was only the decoy message. I can barely read the actual message, and it's about as "readable" to me as the Magic Eye 3D pictures. Actually I think I have a headache from looking at it on a mobile screen. As a research idea it's cool though. But I do wonder if/when AI models will figure out how to…

> ”Took me a long time to realise that "Written In Ghost Text" wasn't actually the text I was meant to be reading, and that was only the decoy message.” Wait, what? Seriously? That’s the only text I can see. Am I an AI?

Have you ever visited the cloud city of Zalem, by any chance? Got any interesting tattoos done on your forehead?

Re: Ghost Font: A font that humans can read but AI cannot

#124

Took me a long time to realise that "Written In Ghost Text" wasn't actually the text I was meant to be reading, and that was only the decoy message. I can barely read the actual message, and it's about as "readable" to me as the Magic Eye 3D pictures. Actually I think I have a headache from looking at it on a mobile screen. As a research idea it's cool though. But I do wonder if/when AI models will figure out how to…

Funny, for me it is exactly the opposite: I can read the actual text very easily, but the “Written in Ghost Text” is barely perceptible to the point I would have completely missed it, if it were not for the comment pointing it out here.

Same, I had no sense of the decoy message at all until I read that comment.

Re: Ghost Font: A font that humans can read but AI cannot

#125
post #99

GPT-5.6 had no problem seeing the text when giving it a video recording of it. "No problem" as in using temporal analysis with optical flow and vertical-displacement maps to estimate how the image moved, and combine those into a motion map with increased contrast to see the text. I didn't give it any instructions though, just asked it what it said.

I threw it at Fable with the prompt "What does the message say?" and it also figured out without issue. Thought process is interesting https://imgur.com/a/GToXs6W

[dead]

Re: Ghost Font: A font that humans can read but AI cannot

#126
post #89
post #82

> For example, it would be interesting to incorporate Ghost Font into CAPTCHA systems, as most systems are easily solved by AI today. It seems to me like it should be easy enough to take Ghost Font, apply normal video compression techniques, and analyze the compressed signal to recover the visual outline of the letters, which you would then analyze with OCR (or an AI I guess ...). In other words, a novel CAPTCHA tech…

I.e. there’s an ffmpeg incantation out there to do it.

An LLM can output it pretty quick, I imagine.

Re: Ghost Font: A font that humans can read but AI cannot

#127
post #82

> For example, it would be interesting to incorporate Ghost Font into CAPTCHA systems, as most systems are easily solved by AI today. It seems to me like it should be easy enough to take Ghost Font, apply normal video compression techniques, and analyze the compressed signal to recover the visual outline of the letters, which you would then analyze with OCR (or an AI I guess ...). In other words, a novel CAPTCHA tech…

I took just two screenshots and applied some filters and got

https://fingswotidun.com/images/GhostFont_2_samples.jpg

https://fingswotidun.com/images/GhostFont_b_2_samples.jpg

An AI would be able to take consecutive frames rather than hamfistedly pressing the screenshot button, then accumulate enough samples to clearly make out the text from a clip shorter than the time it would take for a human to read it.

Re: Ghost Font: A font that humans can read but AI cannot

#128

It is smart, but it is not impossible to crack algorithmically imo. In particular, one can take two consecutive frames and run perturbations moving one frame around (ie shift the indexes) to find where the difference between the two consecutive frames minimises. Then subtract these two (perturbed) frames and ocr it. Works easily if the movement is linear/one-directional. I did this in 20 lines of code (checking only…

Do you mind sharing the code?

Sure! It is in matlab (I know...) so I assume you may want to ask an llm to translate it to python or sth but it should be fairly simple

https://pastebin.com/n1mvcxP1

Re: Ghost Font: A font that humans can read but AI cannot

#129
post #127
post #82

> For example, it would be interesting to incorporate Ghost Font into CAPTCHA systems, as most systems are easily solved by AI today. It seems to me like it should be easy enough to take Ghost Font, apply normal video compression techniques, and analyze the compressed signal to recover the visual outline of the letters, which you would then analyze with OCR (or an AI I guess ...). In other words, a novel CAPTCHA tech…

I took just two screenshots and applied some filters and got https://fingswotidun.com/images/GhostFont_2_samples.jpg https://fingswotidun.com/images/GhostFont_b_2_samples.jpg An AI would be able to take consecutive frames rather than hamfistedly pressing the screenshot button, then accumulate enough samples to clearly make out the text from a clip shorter than the time it would take for a human to read it.

[deleted]

Re: Ghost Font: A font that humans can read but AI cannot

#130

Earlier quoted context omitted.

I threw it at Fable with the prompt "What does the message say?" and it also figured out without issue. Thought process is interesting https://imgur.com/a/GToXs6W

That's the decoy message, "written in ghost font".

I swear people are dumber than the models now, we reached ASI.
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