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Topic review (newest first)

4

An MD5 hash is a string given by a (although fairly broken) hash function, given some input bitstring. Unfortunately, since hash functions are not one-to-one, it is quite difficult to reconstruct the source data (ISO) from just the hash, but with the magic of mathematics, we can, theoretically, convert an MD5 hash to a valid, playable ISO, via the axiom of choice! Allow me to explain.

Let H be our MD5 hash that we want to convert to a playable ISO, and M a Turing machine that accepts the set of bitstrings B that consists of playable ISOs for some fixed system S. We can simply assert the existence of such a machine by the axiom of choice (AC), but we can do even better: we can construct such a machine simply by looking at the code of any emulator for S!

Let MD5 be the MD5 hash function that maps some bitstring b to a hash h

Then, let B (bold and italics are different variables!) be the set of all bitstrings. We simply need to refine this set such that for all bitstrings b in B, MD5(b) = H. Lets call such a set H.

We're basically done at this point. All you have to do is find a bitstring in H that M accepts, and you have your ISO!

3

Or you can see it with numbers:
MD5 data: 32 bytes
SHA1 data: 40 bytes

Smallest bin file: 2116800 bytes (Oretachi Geesen Zoku - Karate-dou (Japan) (Track 2).bin)
Smallest data track: 11056752 bytes (NetFront (Japan).bin)
Average bin file: 2451972041 bytes

2

What are you talking about? MD5 is an algorithm used for file verification purposes. An MD5 file is just a file type that includes the name of the file you want to check and next to it goes the checksum, in this case an MD5 checksum.

If you downloaded an MD5 file from redump, expecting to get an ISO, you're simply so wrong. Redump simply offers a way to make sure that your self-obtained rip (by whatever method you decided to do so) is the same as the one that has redump considered correct.

1

how to covert md5 to iso Original ps2 game

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