Comment by wernsey
15 hours ago
The blog just leads to https://research.swtch.com/qr/draw/, which is the demo page of the blogs [1] and [2] written by Russ Cox many years ago about putting pictures in QR codes by manipulating the error correction codes in them
[1]: https://research.swtch.com/qart [2] https://research.swtch.com/field
Hey thanks a lot, that should be the actual link behind the submission. Very interesting technique that boils down to encode a url with a ton of carefully shaped random numbers hidden in the fragment to generate the actual art.
That's the example url from the linked blog introducing this technique http://swtch.com/pjw/#123456789...
Source Code (Go) is here: https://github.com/rsc/qr/tree/master/qart
Messing with that demo page, it seems to manipulate the URL you put in there too adding some numbers after an anchor tag (#) at the end, rather than just error correction.
Interesting I was wondering about this, if you control the domain and web server technically you could even make a full path of arbitrary data that then redirects to the real target.