Show HN: The text disappears when you screenshot it

(unscreenshottable.vercel.app)

72 points | by zikero 2 hours ago

15 comments

  • alanfalcon 2 minutes ago
    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...
  • xnx 1 hour ago
    This game disappears if you pause it: https://youtube.com/watch?v=Bg3RAI8uyVw
  • Syntonicles 1 hour 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 1 hour 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
  • shannifin 48 minutes ago
    Others have mentioned Branta Games, but I first saw the effect here: https://youtu.be/TdTMeNXCnTs
  • kemayo 1 hour ago
    This makes me feel motion-sick, which is kind of impressive because I'm normally not easily susceptible to that.
    • dylan604 1 hour ago
      My eyes went straight into seeing 3D image mode. It's the easiest one I've seen yet! /s
      • RedShift1 15 minutes ago
        Heh my eyes felt like they started bleeding
  • Izkata 1 hour ago
    Firefox on Android seems to just be a static image, I can't see any text.
  • markasoftware 1 hour ago
    same thing, but a game: https://brantagames.itch.io/motus
  • zikero 1 hour 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 56 minutes ago
      As if captchas aren't painful enough for visually impaired users...
  • bix6 2 hours ago
    Ha cool! How’s it work?
    • Lalabadie 1 hour ago
      The only way to see the text is in the movement. The pattern across any single frame is entirely random noise.
  • altcognito 1 hour ago
    Fun side effect: staring at the letters for a bit makes the rest of the image move.
  • alliancedamages 1 hour ago
    You can also break it by recording the screen, of course.
  • kps 1 hour ago
    The text reappears when I screenshot it twice.
  • cryptoz 2 hours 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 :)
    • vunderba 1 hour 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%.
    • sans_souse 1 hour 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 1 hour ago
        He's right. This is zoomed out: https://imgur.com/a/G7CKZ94

        This is on MacOS 15.6, Chromium (BrowserOS), captured with the OS' native screenshot utility. 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 1 hour 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 1 hour 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 1 hour 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 1 hour ago
            Mine freezes the animation on zoom change. Not sure you could automate against that
  • UltraSane 1 hour ago
    Seems trivial to diff multiple screenshots to identify what parts move. Or just use a compression algorithm to do the same.