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Show HN: The text disappears when you screenshot it

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You can take TWO screenshots, moments apart, open in GIMP, paste one over the other and choose any one of these laying modes:

Lighten, Screen, Addition, Darken, Multiply, Linear burn, Hard Mix, Difference, Exclusion, Subtract, Grain Extract, Grain Merge, or Luminance.

https://ibb.co/DDQBJDKR

4 months agoby axiolite

This game disappears if you pause it: https://youtube.com/watch?v=Bg3RAI8uyVw

4 months agoby xnx

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

4 months agoby Syntonicles

Others have mentioned Branta Games, but I first saw the effect here: https://youtu.be/TdTMeNXCnTs

4 months agoby shannifin

Reminds me a bit of the album cover of _Any Minute Now_ by Soulwax

https://upload.wikimedia.org/wikipedia/en/a/ab/AnyMinuteNow....

4 months agoby geordieboozer

If anybody implements that to antiscrenshot some sensitive data, somebody else will use another phone, a tablet or a camera to record a video of it. Nice idea though.

4 months agoby pmontra

https://gist.github.com/jncornett/d7cb397ce3ceff268a0ee1b86f...

On iPhone: screenrecord. Take screenshots every couple seconds. Overlay images with 50% transparency (I use Procreate Pocket for this part)

4 months agoby catlifeonmars

This makes me feel motion-sick, which is kind of impressive because I'm normally not easily susceptible to that.

4 months agoby kemayo

As soon as I read the title I knew it would be akin to "Bad Apple that disappears when you pause it"

https://www.youtube.com/watch?v=bVLwYa46Cf0

And another version of this, using apples instead of white noise

https://www.youtube.com/watch?v=r40AvHs3uJE

4 months agoby Anonyneko

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

4 months agoby dylan604

This should have an epilepsy warning. Or something of that kind. It certainly made me feel sick.

4 months agoby Aeolun

I'm wondering. Can we also come up with something the other way around? Text you cannot read, unless you take a screenshot?

4 months agoby landgenoot

Nobody seems to have answered yet that you can also use ImageMagick "compare" on two screenshots.

    compare image1 image2 -compose src diff.png

4 months agoby LLyaudet

Nice one, the good (great?) thing is that you can save this as a plain old html and you've got the whole code :-) It hasn't got any type of license included or any other info as comments, so perhaps the creator or the OP can let us know.

4 months agoby NKosmatos

I don't see any text: just a scrolling down screen of random black/white pixels.

4 months agoby oniony

> let textString = `hello`

I think further obfuscation could be possible by uglifying the script and providing a SVG path that stores the text as some vector image.

Self modifying code could be useful too, to delete the SVG data once it is in the canvas.

I fully expect this to still be defeated by AI though, such is my presumption that AI is smarter than me, always. It won't care about uglification and it would just laugh to itself at my humble efforts to defeat Skynet.

Regarding practical applications, nowadays kids sell weed online quite brazenly on platforms such as Instagram. Prostitutes also sell their services on Telegram. It is only a matter of time before this type of usage gets clamped down on, so there may come a time when this approach will be needed to thwart the authorities.

4 months agoby Theodores

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.

4 months agoby zikero

I think there are usecases for this.

Some countries switched to identity apps instead of plastic identity cards. You could make sensitive data non-screenshottable and non-photographable.

A modern variant to the passport anti identity fraud cover: https://merk.anwb.nl/transform/a9b4e52a-9ba1-414b-b199-29085...

The hotel you are checking in doesn't need to know your DOB, length, SSN, birth place, validity and document number. But they will demand a photo of the ID anyway.

4 months agoby landgenoot

Neat! I've seen stuff like this that works as a magic eye thing. So you cross your eyes (or make them parallel, depending on the type of image) and it makes a 3d animation appear in front of the page.

4 months agoby andai

Firefox on Android seems to just be a static image, I can't see any text.

4 months agoby Izkata

You can pass in different text. eg:

https://unscreenshottable.vercel.app/?text=Bonjour

4 months agoby ape4

Cool. I used the Windows snipping tool and just screen-recorded it.

4 months agoby vivegi

On my Chrome-descended browser, the initial screen is populated by something that appears to be some sort of downsampled grid image, resulting in black and white, but also various shades of grey. However the scrolling text is pure black and white. It also seems the canvas is persistent, so the result is that text on the canvas is leaving a shadow for me, where I can still read the shadow. Somehow the initial noise is not coming out as just black and white pixels.

4 months agoby jerf

Doesn't even show anything on LibreWolf, probably disabled WebGL as usual. I thought it was a nice error screen, but apparently it was intended, just without the text :P

4 months agoby wink

Not technically a screenshot, I guess, but trivially easy to do with software I had lying around all the same. https://media4.giphy.com/media/v1.Y2lkPTc5MGI3NjExYXloZ3Z0NT...

4 months agoby alanfalcon

Instead of having the pixels on the letters scrolling down, wouldn't it also work if the pixels were simply re-randomized every frame?

4 months agoby marcodiego

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 :)

4 months agoby cryptoz

I have no idea about anyprogramming at all, but i tried to make chatgpt make a wolfenstein-like game using this concept. It doesnt work but perhaps someone will be interested in the concept: https://pastebin.com/SKAnBPMg

4 months agoby captain123456

I don't see any text, just something like scrolling white noise. I'm able to screenshot it. Am I missing something?

4 months agoby throwaway81523

Ha cool! How’s it work?

4 months agoby bix6

Fun!

I always wanted to make text that couldn't be recorded with a video recorder, but that doesn't seem possible.

Maybe if you knew the exact framerate that the camera was recording at, you could do the same trick, but I don't think cameras are that consistent.

4 months agoby creata

I have to admit it's a pretty cool idea.

At first I was worried that there was a (stupid) API in web browsers just like on mobiles to prevent users from screenshotting something by blanking the screen in the screenshot.

4 months agoby jiehong

It's a nice effect, but I don't think it's usable in practice, because it's not accessible for visually impaired users: not enough contrast between foreground text and background

4 months agoby giamma

This idea has made me think of another subject - would it be possible to overload a face / car plate scanning camera by using a pattern, like qr code for exampl? Or a jacket made of qr codes?

4 months agoby p0w3n3d

So windows 11 easily bypasses this when taking a screenshot. Just switch to video mode. (Yeah yeah. Not technically a screenshot but same default software built in to windows.)

4 months agoby birdman3131

What i am supposed to see here? Its just static noisy background

4 months agoby dgan

Could someone please post what this disappeared bit is supposed to look like? Looks legible to me when I screenshot and open in Preview on MacOS 15.6.1 (Firefox).

4 months agoby shrikant

Even is some have found a workaround, this is a cool feature