4 ms·

I am fascinated by the Truecrypt file histogram. I'd be interested to see a histogram of an encrypted partition or whole file system. Hmm, may not get any work

• dchest 15y ago
  All properly encrypted things should have the same almost uniform distribution.
• jannes 15y ago
  All binary file formats should be randomly distributed along the spectrum if their file size is large enough. Also, I am not sure that this sort of diagram would be suitable to tell certain file types apart, there is probably always a better way to do that. You should notice that the histogram of a zip file, for example, should level out (like the truecrypt histogram does) if the file were as big as the truecrypt file. The look of these histograms is largely influenced by the file size. So, I think only the peaks are worth to interpret.
  • wladimir 15y ago
    All binary file formats should be randomly distributed along the spectrum if their file size is large enough Why would that be the case? - Executables: some opcodes are more common than other, and usually contain text/messages - Zip files / compressed images / mp3s: compression might have a distinct "signature" that has peaks, for example block headers - Database files: not all values are equally common in records (probably peaks around zero, because of fixed-size integers and string padding) And so on...
    • jannes 15y ago
      When I wrote that previous comment I assumed that most binary data would probably use an encoding that is longer/shorter than 8 bit (that's what was examined here). But thinking about it, that might not be true. I don't know.