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Comment by olejorgenb | Hacker News Reader

If the goal is to make it easy to see if two strings are equal, why not display a cryptographic hash of them instead? There is of course a very small chance of collision, but ignoring that? Does the drunken bishop produce unique images given the dimensions and input sequence length used?

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I think the idea is that when a human checks to see if two hashes are equal, they usually just check the first few bytes, and maybe the last few bytes. You could attack this by grinding out hashes to find two with the same first few bytes.

Of course, you could do something similar with this visual algorithm, but I guess the idea is you are using more of the human visual system so it's harder.

In that case we can hash the hash :D + some random number I guess, otherwise it doesn't help much.

This is answered in the article:

> As an example let’s compare two hexes:

> fc94b0c1e5b0987c5843997697ee9fb7

> and

> fc94b0c1e5b0937c5843997697ee9fb7

> are they the same? Let’s use the random art to find out.

Sometimes hashes are visually similar and people aren't always able to compare so finding a different way to represent them could help ensure accurate comparison.

What would be interesting though is if you simply chunk the hash into smaller pieces would it be easier to compare?

> fc94 b0c1 e5b0 987c 5843 9976 97ee 9fb7

> fc94 b0c1 e5b0 937c 5843 9976 97ee 9fb7

I'm sure it depends a lot on the size. If it's a longer string the grid becomes easier, but for shorter strings the chunks would probably suffice.

I don't know about you, but it took me a solid 2 minutes to see the difference (even with the chunks), and less than a second to see the other one.

The example given is especially difficult with any sort of dyslexia, which is where an more visual comparison would really shine

I spent quite a bit of time looking for the most devious swap I could. I still struggle to see it!

I thought the parent meant, provide two hashes, the hash itself and a hash of the hash (a check-hash, if you will).

fc94b0c1e5b0987c5843997697ee9fb7

5e81

fc94b0c1e5b0937c5843997697ee9fb7

d1da

You can see the difference v. clearly now. (hash used is md2 reduced to first and last 2 digits).

This is, effectively, displaying a cryptographic hash. But hashes are long and filled with lots of the same thing, so some software [also] turns them into other things, like "random art" or using a word list to turn a hash into a "sentence".

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