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Show HN: The text disappears when you screenshot it
151–160 of 204 posts
Re: Show HN: The text disappears when you screenshot it
#152You 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
> You can take TWO screenshots, moments apart, open in GIMP, paste one over the other and choose any one of these laying modes: You actually don't need any image editing skill. Here is a browser-only solution: 1. Take two screenshots. 2. Open these screenshots in two separate tabs on your browser. 3. Switch between tabs very, very quickly (use CTRL-Tab) Source: tested on Firefox
You could also just record a video.
Re: Show HN: The text disappears when you screenshot it
#153you can unzoom and then it's screenshotable.
Re: Show HN: The text disappears when you screenshot it
#154Others have mentioned Branta Games, but I first saw the effect here: https://youtu.be/TdTMeNXCnTs
This one is actually more sophisticated because it doesn't rely on scrolling pixels like the OP. So the object doesn't just disappear in screenshots, but also when the animation stops moving! So you can't actually display text that stands still, like the "hello" in the OP.
Yep. He tries text in another video by flipping pixels for one or more frames, so the words disappear very quickly. Definitely harder to read, especially longer words: https://youtu.be/EDQeArrqRZ4
Re: Show HN: The text disappears when you screenshot it
#155Another 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 outli…
Take N screenshots, XOR them pairwise, OR the results, then perform normal OCR.
Yes but this is prohibitively expensive for a large bot network to employ.
Wasn't that the whole point of Anubis?
Re: Show HN: The text disappears when you screenshot it
#156Earlier quoted context omitted.
The only way to see the text is in the movement. The pattern across any single frame is entirely random noise.
> The pattern across any single frame is entirely random noise. This is untrue in at least one sense. The patterning within the animated letters cycles. It is generated either by evaluating a periodic function or by reading from a file using a periodic offset.
They didn't mean random noise as in certifiably truly random in a cryptographic sense... nobody cares about that for a silly demo.
Random noise as in a normal non-tech human cannot see anything discernable to them at all, without the motion component.
Re: Show HN: The text disappears when you screenshot it
#157I'm wondering. Can we also come up with something the other way around? Text you cannot read, unless you take a screenshot?
You could probably do it with timing tricks related to video refresh. Wait until the monitor has finished refreshing, then draw the text into the framebuffer. Leave the text there a short while, but erase it before the monitor starts refreshing again. Repeat.
The screenshot would have a chance of capturing the text, depending on exactly when the screenshot pulls pixel data out of the framebuffer.
This might not work on certain devices. You need access to the refreshing timing information. The capture mechanism used for screenshots might also vary.
Re: Show HN: The text disappears when you screenshot it
#158This game disappears if you pause it: https://youtube.com/watch?v=Bg3RAI8uyVw
Not really a game, but neat all the same.
It reminds me of the mid-1990s video game Magic Carpet.
https://en.wikipedia.org/wiki/Magic_Carpet_(video_game)
This was a pseudo-3D game and on an ordinary display it used perspective to simulate 3D like most games. If you had 3D goggles it could use them, but I didn't.
However, it could do a true 3D display on a 2D monitor using a random-dot stereogram.
https://en.wikipedia.org/wiki/Random_dot_stereogram
If you have depth perception and are able to see RDS autostereograms, then Magic Carpet did an animated one. It was a wholly remarkable affect, but for me anyway, it was really hard to watch. It felt like it was trying to rotate my eyeballs in their sockets. Very impressive, but essentially unplayable and I could only watch for a minute or two before I couldn't stand the discomfort any more.
Re: Show HN: The text disappears when you screenshot it
#159This could be used for Captcha systems. Would current bots be able to decipher these?
Yes, you can make ChatGPT decipher this already.
But doing this on a massive scale would warm the planet.
And it's not friendly accessibility-wise.