Interested in reversing 2d-image formats

Textures, recreate headers, conversions, algorithms and parsing of image files
Anexenaumoon
Posts: 119
Joined: Sun Dec 27, 2015 10:22 pm

Interested in reversing 2d-image formats

Post by Anexenaumoon »

Hey guys, I don't know who can help me (most likely Acewell can get me started, I don't really know xD), but I'm interested in learning how to reverse 2-d image formats. Does anyone have any pointers on where I can start learning how to/examples to trace of how it's done? I have a basic understanding in archives, and I'm looking to expand my knowledge into textures/image formats. Can anyone offer up some advice for a noobie like me?
TheUkrainianBard
Posts: 121
Joined: Sun May 01, 2016 10:06 pm

Re: Interested in reversing 2d-image formats

Post by TheUkrainianBard »

It depends on engine used and platform it was developed for but I'd say it starts with data and visual patterns.
There aren't that many de-facto used compression schemes for textures with BC (Block Compression, aka DXTC or S3TC) being the most ubiquitous.
Acewell
Posts: 706
Joined: Fri Aug 08, 2014 1:06 am

Re: Interested in reversing 2d-image formats

Post by Acewell »

i have about a hundred scripts in their simplest form floating around you can reference along with samples provided in the same threads. :)
you can apply same steps you know from archive extraction to figuring out image formats.
in the headers i look for any combination of width, height, some kind of format ID and datasize.
i usually start with opening samples in TextureFinder to see if anything displays on a common format,
then if no satisfying results i will use Noesis built-in format functionality to identify anything exotic.
and from there just start forming a script and let the tools do the work, not a whole lot to it. :D