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Decayfmt – a file format that corrupts itself a little every time you open it

44 points by unprovable 7 hours ago | 15 comments

This is NOT a file format that corrupts itself. This is a file reader that corrupts files. There's a big difference. Nothing about the format itself causes or requires corruption. A better tagline would be "decayfmt is a social contract enforced by pinky promise".

serbuvlad 2 hours ago

Basically what you want is a custom PCIe device that can P2P DMA the DRM-encrypted frame data to GPU DRM-protected memory directly, more corrupted each time.

Can still be replayed, but would likely require special hardware to do so.

aureate 3 hours ago

Dammit! This renders it completely unusable.

jasonpeacock 4 hours ago

Reminds me of Tie::Hash::Cannabinol:

  Tie::Hash::Cannabinol is a completely useless demonstration of how to use Tie::StdHash to 
  pervert the behaviour of Perl hashes. Once a hash has been tied to Tie::Hash::Cannabinol, 
  there is a 25% chance that it will forget anything that you tell it immediately and a 
  further 25% chance that it won't be able to retrieve any information you ask it for. Any 
  information that it does return will be pulled at random from its keys.
  
  Oh, and the return value from exists isn't to be trusted either :)

[1] https://metacpan.org/pod/Tie::Hash::Cannabinol

fnordlord 33 minutes ago

From what I remember, MS Paint do something similar when you would save the image as a jpeg. It would apply the algorithm each save and the image would degrade a bit each time. It was super fun.

jolmg 5 hours ago

> This is a social contract

What's the other side of the contract? Why would a reader oblige to corrupt?

mdp2021 17 minutes ago

Probably satire. Like: "social contract: you will allow fools to choose your government".

angeldimitrov94 5 hours ago

Seems like there is no mechanism to allow non-corrupting reads from authorized processes? Begs the question then of what the point of this is. Pure novelty, or truly something that could be used in practice?

dang 5 hours ago

Kind of like how human memory works, if I understand correctly.

yboris 2 hours ago

A better analogy would be if every time you played the video file, the mechanism hallucinated a little, bringing in your current feelings as input to change the emotional undertones (and possibly characters and events) depicted in the video.

NDlurker 5 hours ago

Should have patented it and licensed it to Snap

m3047 4 hours ago

You might look into (Norbert) Weiner functions.

m3kw9 5 hours ago

I thought something like this should be part of the file system to make it even more laborious to by pass

dylan604 4 hours ago

A company I was at had a disk array that would do something like this. It wasn't a documented feature mind you. During writes, it would randomly zero out data within a file. So at least it didn't get progressively worse, but it was a bear to isolate. These were large media files so a quick look at the head/middle/tail could easily miss the problem areas.

M95D 4 hours ago

Would you please stop inventing more ways to enshittify the world?