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How to Store Data on Paper?

monperrus.net

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Re: How to Store Data on Paper?

#11

Post by spencerflem »

tocs3 wrote: post #3

I have been thinking about this for a long time. Thanks for the link. The biggest advantage of character-based encodings is that they can be decoded by humans (as opposed to dot-based encodings), which means that you don’t need a camera or a scanner to recover the data. This is an interesting point. In our post apocalyptic future scholars will be using their quills to translate archives of these (in my imagination an…

I think for that use-case (copying by quill), just writing plaintext from the start would be the move

Re: How to Store Data on Paper?

#12

Post by usrbinbash »

tocs3 wrote: post #3

I have been thinking about this for a long time. Thanks for the link. The biggest advantage of character-based encodings is that they can be decoded by humans (as opposed to dot-based encodings), which means that you don’t need a camera or a scanner to recover the data. This is an interesting point. In our post apocalyptic future scholars will be using their quills to translate archives of these (in my imagination an…

> In our post apocalyptic future scholars will be using their quills to translate archives of these

Imagine tomes of programming lore, dutifully transcribed by rooms of silent scribes, acolytes carrying freshly finished pages to and fro, each page beautifully illuminated wih pictures of the binary saints, to ward off Beelzebug.

Re: How to Store Data on Paper?

#13

Post by CorrectHorseBat »

mackmgg wrote: post #8
tocs3 wrote: post #3

I have been thinking about this for a long time. Thanks for the link. The biggest advantage of character-based encodings is that they can be decoded by humans (as opposed to dot-based encodings), which means that you don’t need a camera or a scanner to recover the data. This is an interesting point. In our post apocalyptic future scholars will be using their quills to translate archives of these (in my imagination an…

> Is this right? Wouldn't it be base-3 encoding? Three bits of binary can count to 8. Three trits of base three can count to 27. Color has all sorts of disadvantages but maybe a much greater payoff (unless I m mistaken). In this case they're not directly using the color to store information, they just have three differently colored QR codes overlayed on top of each other. With that method you can use a filter to sepa…

>this case they're not directly using the color to store information, they just have three differently colored QR codes overlayed on top of each other. With that method you can use a filter to separate them back out and you've got three separate QR codes worth of data in one place. The way they're added ends up using more than just three colors in that example.

That's only true if you can print and read colors in a higher resolution/don't destroy information at 3x the density with color, I'm not sure if that's generally true.

>If you were truly to use colored dots to store binary information without worrying about using a standard like QR, I think you'd be going from base-2 (white and black) to base-3 (red, blue, green) or more likely base-4 (white, red, blue, green) or even base-8 (if you were willing to add multiple colors on top of each other) in which case yeah you'd have way more than just 3x the data density.

Base 8 is exactly 3x the data density. (Log(8)/log(2))

Re: How to Store Data on Paper?

#14

Post by bartvk »

makeworld wrote: post #6

I wonder if you could add error correction to get around OCR failures.

You could simply add a par2 file but the default setting makes it pretty big. I just tried on an 876 kB Word file. And I got a bunch of par files totaling 1158 kB. The man page says it'll correct up to 100 errors.

Re: How to Store Data on Paper?

#16

Post by Joker_vD »

bartvk wrote: post #14
makeworld wrote: post #6

I wonder if you could add error correction to get around OCR failures.

You could simply add a par2 file but the default setting makes it pretty big. I just tried on an 876 kB Word file. And I got a bunch of par files totaling 1158 kB. The man page says it'll correct up to 100 errors.

You could replicate the Word file twice, using 1752 kB, and it'll correct up to ≈7 million one-bit errors as long as there is at most one error at three equivalent bit offsets.

Re: How to Store Data on Paper?

#17

Post by sweettea »

usrbinbash wrote: post #12
tocs3 wrote: post #3

I have been thinking about this for a long time. Thanks for the link. The biggest advantage of character-based encodings is that they can be decoded by humans (as opposed to dot-based encodings), which means that you don’t need a camera or a scanner to recover the data. This is an interesting point. In our post apocalyptic future scholars will be using their quills to translate archives of these (in my imagination an…

> In our post apocalyptic future scholars will be using their quills to translate archives of these Imagine tomes of programming lore, dutifully transcribed by rooms of silent scribes, acolytes carrying freshly finished pages to and fro, each page beautifully illuminated wih pictures of the binary saints, to ward off Beelzebug.

See also: the first part of A Canticle for Leibowitz.

Re: How to Store Data on Paper?

#18

Post by vubecnevim »

And now imagine you could save not just text or images or music but also more abstract things like emotions and meaning. And now imagine you can do it in a true human readable form so that many people (not just scholars or priest with secret knowledge) in a post apocalyptic or indeed a normal future can read it. And now imagine that only a limited set of characters even very simple ones can store that data even in just one character measuring just enough space so one can read it. How awesome is that? And we already have this system and it was developed thousads of years ago.

Re: How to Store Data on Paper?

#19

Post by bob1029 »

Something like PDF417 would be what I reach for if I needed a very robust physical representation.

I've seen these barcodes scan accurately off dingy plastic cards using webcams.

The information level per symbol is not great (about 1kb), but the error correction and physical layout work really well.

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