You can switch modes. (Yes that costs a dozen bits if you were otherwise able to stay in the same mode the entire time. Oh well, but I'd say it's worth it to avoid base45.)
And base45 is less efficient than looking at the efficiency of raw alphanumeric.
Alphanumeric is the most efficient QR code encoding mode.
(Just to further make this clear, for QR Byte encoding uses ISO/IEC 8859-1, where 65 characters are undefined, so 191/256, which is ~75%. If character encoding isn't an issue, than byte encoding is the most efficient, 256/256, 100%, but that's a very rare edge case. Also, last time I did the math on Kanji it was about 81% efficient. *I have not dug too deep into Kanji and there may be a way to make it more efficient than I'm aware of. I've never considered it useful for my applications so I have not looked.)
Dylan16807|1 year ago
And base45 is less efficient than looking at the efficiency of raw alphanumeric.
Zamicol|1 year ago
Not according to my math:
Numeric: 1000/1024 = 98%
Alphanum: 2025/2048 = 99%
Byte: 191/256 = 75%
Kanji: 13/16 = 81%*
Alphanumeric is the most efficient QR code encoding mode.
(Just to further make this clear, for QR Byte encoding uses ISO/IEC 8859-1, where 65 characters are undefined, so 191/256, which is ~75%. If character encoding isn't an issue, than byte encoding is the most efficient, 256/256, 100%, but that's a very rare edge case. Also, last time I did the math on Kanji it was about 81% efficient. *I have not dug too deep into Kanji and there may be a way to make it more efficient than I'm aware of. I've never considered it useful for my applications so I have not looked.)