Show HN: The text disappears when you screenshot it

36 zikero 25 9/18/2025, 2:18:45 AM unscreenshottable.vercel.app ↗

Comments (25)

shannifin · 3m ago
Others have mentioned Branta Games, but I first saw the effect here: https://youtu.be/TdTMeNXCnTs
xnx · 42m ago
This game disappears if you pause it: https://youtube.com/watch?v=Bg3RAI8uyVw
vunderba · 34m ago
This is great - seems to be the same effect of hiding a shape using an animated noise pattern on a background of static noise.

They even provide the source code for the effect:

https://github.com/brantagames/noise-shader

Syntonicles · 27m ago
I first saw this effect in a video from Branta Games.

https://www.youtube.com/watch?v=Bg3RAI8uyVw

The effect is disrupted by introducing rendering artifacts, by watching the video in 144p or in this case by zooming out.

I'd love to know the name of this effect, so I can read more about the fMRI studies that make use of it.

What I've found so far:

Random Dot Kinematogram

Perceptual Organization from Motion (video of Flounder camouflage)

https://www.youtube.com/watch?v=2VO10eDIyiE

dylan604 · 50m ago
Has anyone tried a long exposure to see if the motion smears into something discernible? Obviously harder to expose a bright screen without some ND since the shutter speed is the phone's main exposure control
markasoftware · 41m ago
same thing, but a game: https://brantagames.itch.io/motus
Izkata · 1h ago
Firefox on Android seems to just be a static image, I can't see any text.
zikero · 40m ago
Another idea I had with this concept is to make an LLM-proof captcha. Maybe humans can detect the characters in the 'motion' itself, which could be unique to us?

- The captcha would be generated like this on a headless browser, and recorded as a video, which is then served to the user.

- We can make the background also move in random directions, to prevent just detecting which pixels are changing and drawing an outline.

- I tried also having the text itself move (bounce like the DVD logo). Somehow makes it even more readable.

I definitely know nothing about how LLMs interpret video, or optics, so please let me know if this is dumb.

squigz · 11m ago
As if captchas aren't painful enough for visually impaired users...
kemayo · 55m ago
This makes me feel motion-sick, which is kind of impressive because I'm normally not easily susceptible to that.
dylan604 · 48m ago
My eyes went straight into seeing 3D image mode. It's the easiest one I've seen yet! /s
kps · 32m ago
The text reappears when I screenshot it twice.
alliancedamages · 47m ago
You can also break it by recording the screen, of course.
altcognito · 1h ago
Fun side effect: staring at the letters for a bit makes the rest of the image move.
bix6 · 1h ago
Ha cool! How’s it work?
Lalabadie · 1h ago
The only way to see the text is in the movement. The pattern across any single frame is entirely random noise.
UltraSane · 33m ago
Seems trivial to diff multiple screenshots to identify what parts move. Or just use a compression algorithm to do the same.
cryptoz · 1h ago
Had a lot of fun trying to break this. Turns out you can screenshot real easily by zooming out. Maybe there are other ways but I stopped trying :)
sans_souse · 1h ago
Not sure what you mean - I can screenshot it freely that's not the point the point is if you look then at the screenshot you cant discern the text because its a single frame now
esafak · 56m ago
He's right. This is zoomed out: https://imgur.com/a/G7CKZ94

This is on MacOS 15.6, Chromium (BrowserOS). Since I was asked about the zoom factor, I now tried simply capturing it at 100% and it was still perfectly readable...

I guess the trick doesn't work on this browser.

dylan604 · 43m ago
I zoomed out to 90% and could make out something was there but wasn't easy to read. Zooming out further went back to just being noise. I also tried zooming in but with no success. What zoom level did you use and I guess we have to ask the standard what browser/version/OS/etc?? My FFv142 on macOS never took a screen grab like you did
dwg · 1h ago
Zooming out before taking screenshot and the text is no longer obfuscated. I tried and confirmed it works. In fact, the text is perhaps even more readable than the original.
anigbrowl · 57m ago
It depends how fast or slow your GPU is. I tried it and saw the effect you described, but within a second or two it started moving and was obscured again. Obviously you could automate the problem away.
dylan604 · 42m ago
Mine freezes the animation on zoom change. Not sure you could automate against that
vunderba · 41m ago
yeah - I actually was initially confused since I wasn't having any issues screenshotting it but had forgotten that I have the default site zoom set to ~65%.