How to rip games ressources fron adf files ?

[Piru]

I'm planning to rewrite, with SDL, some of the old Amiga classic games and I'm looking for a way to get/rip ressources (gfx, sound....) from a ".adf" file.

You must contact the artwork copyright owner for permission first. You can't reuse artwork even if the game is released for community.

Does someone can explain me how to remove this protection and access to game's data ?

There are no free rides here.

It's painstaking reverse engineering of the game loaders, decrypters and decoders. You need to be able to interpret m68k assembly code and write your own loaders/decoders to load the data. If you want to use music, you need SDL audio modplayer that is able to play the moduleformat used in the game.

I hope, I won't be obliged to use an hex editor !

Hex editor won't help you.

[Piru]

The game's editor doesn't exist anymore, and no one has bought game's rights so I think it will be OK...

It's not.

It's not about the game's editor being gone or game not being sold anymore. It's about intellectual rights of the original artists, their copyright. The copyright does not expire even if the game is abadoned.

If any game license or distribution right expires, the artwork rights automagically return to original author (unless if otherwise agreed, but if unknown, you must assume this is the case).

Contact the artwork author for permission. For such project, you're likely to get the permission, esp. if it's used just for non-public demostration purposes, and the graphics are to be replaced later.