It turns out that, at the bottom right of the project page I pointed to in my previous post, there’s a link to a Windows implementation of their system. I hadn’t noticed that; thanks to James Hung-Kuo Chu, first author of the work, for the tip-off. He has a nice example of a colored QR code on his web page.

The Windows program works! Set a URL or text to search, upload a picture, ask for a QR code.

Here’s an example. Blur your eyes to help you figure out what well-known computer graphics image it represents. I find you’ll want to have the QR code be not very large in your camera’s view for it to be detected as one.

A smaller one, of me. Again, blur eyes. When changing the size it’s likely best (?) to “pixel resize” (sample and hold, etc.), not resampling.

Addendum: James Hung-Kuo Chu, the first author on the paper, noted that using the “Apply contrast enhancement” can give a better result. Here’s one with that:

Addendum 5/28/2023: I just noticed this article, pointing to another QR image generator. The color one’s more fun, IMO, but I wanted to scribble down where this other tool is.
And addendum 6/7/2023: this cool QR maker guided by Stable Diffusion (thanks to Andrew Glassner for pointing it out). Actual creator tool here.
Also, 12/14/2023: a research topic is to make a 2D barcode that tries to be more aesthetically pleasing than a QR code. Me, I think that ship has sailed – adopting a new barcode format seems unlikely – but, interesting topic and a view of “what might have been.”