8 ms·

"DO NOT COMPRESS ANY DATA WITH THIS PROGRAM UNLESS YOU ARE PREPARED TO ACCEPT THE POSSIBILITY, HOWEVER SMALL, THAT THE DATA WILL NOT BE RECOVERABLE." So why wo

"DO NOT COMPRESS ANY DATA WITH THIS PROGRAM UNLESS YOU ARE PREPARED TO ACCEPT THE POSSIBILITY, HOWEVER SMALL, THAT THE DATA WILL NOT BE RECOVERABLE." So why would anybody, hobbyist or enterprise, use this? Or does something older like 7zip also have this caveat that I've never experienced.

fmx 9d ago
This big warning gave me pause, too. Why not have a compression option that automatically checks the data after compression (by decompressing and checking against a hash of the original data), which would reduce the probability of undetected errors to that of a hash collision? i.e. like `7z a` followed by `7z t`, but in one command.
jubilanti 9d ago
Is that all that different than the standard MIT License: > THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE....
- ibejoeb 9d ago
  Practically, no. But that specific disclaimer could lead on to think that there may have been some observed data corruption in practice that isn't disclosed. I have no idea if there is, but I'm not keen to discover it myself. Also practically, this isn't MIT. It is LGPL 3, which I believe includes the warranty terms of GPL 3, i.e., no warranty. So we're in the same place anyway.
palaiologos 9d ago
Tool author here. bzip2 also has this clause, in fact it has been lifted from its dist tarball README verbatim. So does lzma, xz, or in practice any open source program that you use.
- IvanK_net 9d ago
  Hey, I am the creator of https://www.photopea.com https://www.photopea.com and if a user decides to publish their work, it compresses PSD files (inside a browser) and sends them to the server for storing. Right now, we have about 2 TB of files. I use the DEFLATE compression which I fully implemented myself (compressor and decompressor, inside a library called UZIP.js). I wish I could use something better :D but it must be implemented in Javascript to run inside a browser, and the library should not be too large (mine is about 8 kB ZIPped). I would love to switch to ZSTD once someone implements a compressor in Javascript that is under 40 - 60 kB. Or do you think that bzip3 could be re-implemented easily in JS using some AI? I really admire you for being so smart at such a young age :) I wish you best of luck in your scientific career! I visited Warsaw this year, but I am not sure if that is where you are from :D
  - palaiologos 8d ago
    Hi Ivan, Please send me an e-mail! Perhaps we can figure something out.

fmx 9d ago

This big warning gave me pause, too. Why not have a compression option that automatically checks the data after compression (by decompressing and checking against a hash of the original data), which would reduce the probability of undetected errors to that of a hash collision? i.e. like `7z a` followed by `7z t`, but in one command.

jubilanti 9d ago

Is that all that different than the standard MIT License: > THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE....

ibejoeb 9d ago
Practically, no. But that specific disclaimer could lead on to think that there may have been some observed data corruption in practice that isn't disclosed. I have no idea if there is, but I'm not keen to discover it myself. Also practically, this isn't MIT. It is LGPL 3, which I believe includes the warranty terms of GPL 3, i.e., no warranty. So we're in the same place anyway.

palaiologos 9d ago

Tool author here. bzip2 also has this clause, in fact it has been lifted from its dist tarball README verbatim. So does lzma, xz, or in practice any open source program that you use.

IvanK_net 9d ago
Hey, I am the creator of https://www.photopea.com https://www.photopea.com and if a user decides to publish their work, it compresses PSD files (inside a browser) and sends them to the server for storing. Right now, we have about 2 TB of files. I use the DEFLATE compression which I fully implemented myself (compressor and decompressor, inside a library called UZIP.js). I wish I could use something better :D but it must be implemented in Javascript to run inside a browser, and the library should not be too large (mine is about 8 kB ZIPped). I would love to switch to ZSTD once someone implements a compressor in Javascript that is under 40 - 60 kB. Or do you think that bzip3 could be re-implemented easily in JS using some AI? I really admire you for being so smart at such a young age :) I wish you best of luck in your scientific career! I visited Warsaw this year, but I am not sure if that is where you are from :D
- palaiologos 8d ago
  Hi Ivan, Please send me an e-mail! Perhaps we can figure something out.