> Huh? I don't necessarily care about an exact "base45", I care about QR code alphanumeric
> I suspect your referring specifically to RFC base45
> For more detail of my work, my BASE45 predates the RFC by 2 years in 2019
The RFC was linked in the comment I originally replied to. The same comment where you saw the term "base45", because I didn't repeat it in my original reply.
> The way we calculate this, for example, 2025/2048, we've termed "bit space efficiency". I'm not sure how commonly adopted this term is used in the rest of the industry.
It's not a good metric when the size can vary.
3/4 uses 75% of the bit space, and 512/1024 uses 50% of the bit space. But if you give 20 bits to each, the first method can encode 59049 combinations and the second method can encode 262144 combinations.
> which is somewhat absurd considering that the bit is the quantum of information, again as shown by Shannon. There is no such thing as a partial bit that can be communicated, since information is fundamental to communication, so the fractional representation we've found to be more informative and easier to work with.
You can use any base and the math is roughly the same.
Distinguishing between two symbols is just the minimum. You can't transmit .3 bits but you can easily transmit 2.3 bits. If your receiver can distinguish between 5 symbols at full speed then 2.3 bits at a time is the most natural communication method.
> There are other considerations, like padding and escaping, that makes exact calculation more difficult than it's worth. I just needed to "most of the time" calculation and that's where I stopped.
Yeah, that's fine. They're both efficient. My deciding factor is not the tiny difference in efficiency, it's the ill-behaved symbols in alphanumeric.
> I suspect your referring specifically to RFC base45
> For more detail of my work, my BASE45 predates the RFC by 2 years in 2019
The RFC was linked in the comment I originally replied to. The same comment where you saw the term "base45", because I didn't repeat it in my original reply.
> The way we calculate this, for example, 2025/2048, we've termed "bit space efficiency". I'm not sure how commonly adopted this term is used in the rest of the industry.
It's not a good metric when the size can vary.
3/4 uses 75% of the bit space, and 512/1024 uses 50% of the bit space. But if you give 20 bits to each, the first method can encode 59049 combinations and the second method can encode 262144 combinations.
> which is somewhat absurd considering that the bit is the quantum of information, again as shown by Shannon. There is no such thing as a partial bit that can be communicated, since information is fundamental to communication, so the fractional representation we've found to be more informative and easier to work with.
You can use any base and the math is roughly the same.
Distinguishing between two symbols is just the minimum. You can't transmit .3 bits but you can easily transmit 2.3 bits. If your receiver can distinguish between 5 symbols at full speed then 2.3 bits at a time is the most natural communication method.
> There are other considerations, like padding and escaping, that makes exact calculation more difficult than it's worth. I just needed to "most of the time" calculation and that's where I stopped.
Yeah, that's fine. They're both efficient. My deciding factor is not the tiny difference in efficiency, it's the ill-behaved symbols in alphanumeric.