[KGIII]

Doesn't the QR standard allow lowercase via hex and have a miniature version? I know it has error correction, but I'm not sure if it is tunable. I know it can embed kanji, so it seems odd that lowercase would be much of a problem?

Thanks!

I am pretty grateful I'm not tasked with implementing these.

[masklinn]

It's not that lowercase is a problem, it's that aztec is more efficient at it.

Note that GP is incorrect that you need lowercase to express URLs and qrcode has an "alphanumeric" mode (based around uppercases which works fine), but even then qrcode's alphanumeric mode is slightly less efficient as it needs 5.5 bits per character versus 5 for Aztec.

Kanji has its own qrcode encoding mode (the qrcode encoding modes are numeric, alphanumeric[0], byte, kanji, structured append[1], ECI[2] and Code128[3]).

[0] digits, uppercase ascii letters and 9 symbols

[1] to split messages across multiple codes

[2] additional "local" encodings: https://strokescribe.com/en/ECI.html

[3] https://en.wikipedia.org/wiki/Code_128

[KGIII]

I don't really like HN for the links. I can find those anywhere.

What I do like about HN is the comments. Someone here usually knows what they are talking about and can explain it well.

Thanks!

[zo1]

QR codes have variable-level error-correction, from 7-30%.

https://en.wikipedia.org/wiki/QR_code#Error_correction

[KGIII]

Thanks! As mentioned above, I am so glad I'm not one of the folks who has to implement this stuff.

I'd ask why they didn't just improve QR codes, instead of making yet another format, but I'm not sure I want to know the answer(s).