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universal cellular automata or

category: code [glöplog]
baah: nice :)
added on the 2012-03-10 14:47:55 by rudi rudi
ok, finally i managed to decrypt xor patterns by using a cellular automata. this one only (maybe unfortunately) need one bit on each row to specify how the whole pattern will be in the end. but it only need the one dimension. that is in a 640x320 grid it needs the 320 bitvalues to generate the reverse-engineered grid of the original pattern. a pattern that for example was generated with random initial values.

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added on the 2012-03-10 16:18:24 by rudi rudi
Why the mirroring?
Btw, I'm making some code for this as well.
added on the 2012-03-10 17:25:14 by nitro2k01 nitro2k01
raymarching 3d cellular automatons evolving in real time in 3.. 2..
raytraced
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added on the 2012-03-10 20:38:47 by Hyde Hyde
Damn that's cool.
nitro2k01: the upper part of the image is the cellullar automata that generates the xor pattern. the lower part is the decrypted pattern. thats why it is mirrored.
added on the 2012-03-10 21:04:14 by rudi rudi
if i where to go backwards then it wouldnt have been mirrored, but the image was just to show that the patterns are equal from the last row of cells (which are the initial configuration of the decrypted algorithm).
added on the 2012-03-10 21:12:52 by rudi rudi
So, I made a program which generates this kind of pattern. Pic dump:

This is after a round in phl0tosharp.
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Other various raw images and experiments. Some are straight rule 30/110. Others are my own experiements. I've mostly seeded them with 1's at prime number places.

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[imghttp://i.imgur.com/R9J0n.png][/img]

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added on the 2012-03-10 21:13:46 by nitro2k01 nitro2k01
nitro2k01: aweness
added on the 2012-03-10 21:23:22 by rudi rudi
I wonder what that sounds like when fed to a soundbuffer in a good way...
Tried opening the output from my program as an audio file, (1 bit per pixel) and no luck. Sounds mostly like high pitched digital noise (which it is). Maybe there are other ways to get useful sounds out of this, but they're no trivial. (Maybe for example interpreting the bits as 8 bitd in s byte. Might just work. :) )
added on the 2012-03-10 22:05:43 by nitro2k01 nitro2k01
I was thinking, maybe you could take the input and play it as if it was a spectrogram.
@Hyde: cool new view...
added on the 2012-03-11 10:47:58 by baah baah
there. now i dont need bit for each column. now i can decrypt the whole pattern with another CA-rule :P
added on the 2012-03-11 11:46:51 by rudi rudi
baah: thanks, used Exposure Render:
http://code.google.com/p/exposure-render/

It's good fun, dl the binary, create your volume data and store it in a test.raw file, add a .mhd file that contains something like the following:
Code: ObjectType = Image NDims = 3 BinaryData = True BinaryDataByteOrderMSB = False CompressedData = False TransformMatrix = 1 0 0 0 1 0 0 0 1 Offset = 0 0 0 CenterOfRotation = 0 0 0 ElementSpacing = 1 1 1 DimSize = 128 128 128 AnatomicalOrientation = ??? ElementType = MET_SHORT ElementDataFile = test.raw


and load the .mhd-file in Exposure Render.
(this mhd-file specifies 16 bit ints, so the density voxels in .raw should be of that type.)
added on the 2012-03-11 13:30:02 by Hyde Hyde
after a day of painfull work i finally managed it.
this is the result of rule30 encryption. it starts reverse-engineering of the last row of the original rule30-generation, encrypts the resulting row on each time step to finally come back to the original initial black cell:

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added on the 2012-03-11 21:11:31 by rudi rudi
Awesome, the pattern looks like a bird or something.
i don't know what wolfram means with cryptanalysis. the decryption of rule 30 is very simple. its almost as simple as generating the random numbers of the center column in rule30 in the first place. now i havent checked whether this works at longer sequences, but i guess that it is as complete as it can be.
added on the 2012-03-11 22:18:43 by rudi rudi
rudi: Where does it say anything about cryptanalysis? Maybe you just wrote ca first and WA decided to interpret that as cryptanalysis instead of cellular automaton?
added on the 2012-03-12 00:00:58 by nitro2k01 nitro2k01
nitro2k01: no, sorry. it wasnt Wolfram who said that, but someone else. here: http://forum.wolframscience.com/archive/topic/show/231

Quote:
Richard Feynman tried to cryptanalyse rule 30 without success. Some partial progress on decrypting rule 30 sequences given enough information was made in the early 90s (see note on page 1087), but requires essentially a complete column of the rule's evolution. If you can find any significant deviation of the behavior of the center column of rule 30 from perfect randomness, it would be news.


I just wonder what it this means?

What I am at the time being just out after if someone has allready done this. I have not the NKS-book. I will order it as soon as possible so I can read and find out. If anyone allready knows please tell me. I've tried to search this info without finding that much about it.

My plan is to try this on rule 54 because i've read that it is irreversible.
added on the 2012-03-12 01:15:47 by rudi rudi
if someone has this book and read page 1087, please tell me about it! hehe
added on the 2012-03-12 01:16:54 by rudi rudi
What does "Feynman tried to cryptanalyse rule 30" even mean. Reverse it?
Lord Graga: I think so, but i am not sure. Someone should confirm if this is true.

one does not need the complete column, one only need half of the last row. one can go back as many times as the exact evolution of cells one got. to get the CA one needs atleast the last half row of cells (including the center).
added on the 2012-03-12 10:08:38 by rudi rudi
i have yet to read and understand this: http://www.mathpages.com/home/kmath439/kmath439.htm if its the same technique that i am using and if it really is a method to reverse it, but it seems to be more complicated to understand. or atleast the definitions they use for me are a bit to formal to understand.
added on the 2012-03-12 10:16:27 by rudi rudi

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