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
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.
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.
Made me wonder how easy it is to embed QR codes inside everyday images/objects without them being visible until you scan the object.
Does this mean you could make a gif which is a valid QR code playing Bad Apple?
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.
Made me wonder how easy it is to embed QR codes inside everyday images/objects without them being visible until you scan the object.
Does this mean you could make a gif which is a valid QR code playing Bad Apple?
Yes: https://www.reddit.com/r/touhou/comments/ueo304/i_played_bad...
https://news.ycombinator.com/item?id=40377122
A series of QR codes that each link to the next frame of bad apple is the logical conclusion to me