As I'm working as a mobile software technician, a lot of times I need to unpack some Odin firmware to add or remove some files, maybe adding some languages which aren't available in the firmware, then I repack it again so I can flash it with Odin. Thus, I need to understand Samsung firmware structure, I need to know how exactly the system works.
For example, Samsung Galaxy S III I747 is a US phone which comes with only 3 languages. If I want to add some other languages to its firmware, then I need to understand the CSC tree first, so I can edit it and add the desired languages pack.
I've been searching around for some tutorials about that but I couldn't find any. I know how to unpack and repack Odin files, but as I said, I need to understand the system.