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Comment by gruez | Hacker News Reader

>turned out the password protection is useless, all assets and everything are in there unprotected, including the 3D models inside

That's only true for the edit protection password, which obviously can't be implemented in a foolproof way, and therefore it's an honor system.

https://en.wikipedia.org/wiki/Microsoft_Office_password_prot...

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Why “obviously”? The file could contain two parts, one encrypted PowerPoint part with all data and original assets, and the latter just the “rendered” version with everything pruned down to what is needed to display the content. Pair this with some hashing which is signed/stuffed in the encrypted part and any PowerPoint copy would be able to detect tampering as well. Seems obviously trivial.

It's non-trivial to determine "what is needed to display the content". The closest you have is something like "print/save to pdf", which is too lossy for some (eg. you lose animations and comments), and isn't 100% foolproof either (eg. if you use rectangle tool to redact some text, you can still recover what's underneath).

If you have animations the result can be rendered as a video before storing.

One could argue that the reader of a password protected presentation also shouldn’t have access to the contents etc.

If it is allowed to, this could even be exported to a separate section with a different password.

> you lose animations

lol. lmao, even.

https://mirrors.mit.edu/CTAN/macros/latex/contrib/animate/an...

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