qtza?

mattgolsen's picture

I'm not sure if any of you all have seen this, but I ran across the program PulpMotion the other day, and realized that the majority of the themes etc. were built in Quartz Composer. When you view the package contents you'll eventually come across the source composition, with the extension .qtza, which I think is some sort of compressed file type.

Any idea what it might be?

smokris's picture
Probably proprietary encrypted container

I'm guessing it's some sort of proprietary encrypted composition container format --- they probably don't want end-users (or demo-users) to be able to extract assets from it.

OS X's 'file' command doesn't return anything useful:

% file /Applications/gfx/misc/PulpMotion Advanced.app/Contents/PlugIns/Compositions/Autumn.pmCompo/Contents/Resources/Autumn.qtza 
Autumn.qtza: data

...which probably means it's some homebrew.

cwright's picture
protection

Further, the compositions probably perform the watermarking, and have inputs to control whether it marks it or not -- if you could open/edit the composition, you could control that.

Doing a bit more analysis, hexdumping the qtza files gives pretty common headers, so if you can find the algorithm it's probably simple to extract the key given some chosen plaintext (a simple cryptanalytic technique). It might be a simple stream cipher, a position-dependent cipher, or something as simple as an xor cipher.

[EDIT: should disable future comments to prevent possible dmca-takedown-worthy discussion on this topic...]