Acmlm's Board - I2 Archive - Rom Hacking - How does one decompress...
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Fyxe
Posts: 36/1160 |
Thanks guys, this has been quite helpful. ^-^ Still seems like a heck of alot of work for the games for which the offsets are not available... Sniff, eh? I hope I can get it working when I need to. Thanks again. |
Ok Impala!
Posts: 31/383 |
Ok!
Never thought of that last point before, stupid me. 
Many thanks for that hint Chickenlump!  |
Chickenlump
Posts: 110/722 |
For those games that Lunar Compress does support, use the Sniff program that comes with Lunar Compress. It's reletively easy to load up a rom, and have Sniff compile a huge text file listing all possible compressed locations. It's even customizeable, you can tell it to omit results based on compressed file sizes, and much more, to cut down on false results
(not everything that is compressed is graphics though, map data, palettes, text and who knows what else can be compressed also).
If you suspect that an unsupported rom is compressed, feel free to try it anyway, it may be possible that some games share compression techniques (only if your desperate, something tells me not many will, unless it's made by the same company of a supported game ....... ).
Also, don't dismiss any file you decompress and view in a tile editor, and the graphics don't show up right away, remember to switch between graphics modes, as some simple graphics and fonts can be viewed only in Gameboy and NES modes. |
JLukas
Posts: 3/51 |
Here's a quick tutorial on using Lunar Decompress. Let's say you wanted to decompress graphics in Chrono Trigger.
1. Open the LunarDLL.h file with Notepad or whatever, and scroll halfway down. You'll find a Compression Format Table. There you'll see the format, game and usage and description. You'll see Chrono Trigger is format LZ_LC13.
2. Open LunarDLL.def with Notepad. Right at the top you see LZ_LC13 followed by 12, the number Lunar Decompress assigns to that format.
3. Open a DOS prompt and type
Decomp.exe chronotrigger.smc output.bin 166C12 12 0
4. Open the output file in Tile Layer Pro or other program and you'll find you decompressed the graphics for a Nu. But how do you know the offset to start from is 166C12? That's where you look at an offsets guide that lists where things are stored.
If the game you want to decompress doesn't have an offsets guide, you'll have to find where the compressed graphics are on your own. Your main goal would be to find a pointer table(s) that the game uses to locate where the compressed graphics are. Then just work your way through the pointer list, decompressing each offset as you go along.
Hope this helps. |
Darth Coby
Posts: 435/1371 |
You need to write an application that can perform the decompression routine, that one you'll first have to find though.  |
JaCory
Posts: 167/323 |
There are many compression types and decompressors. What games gfx are you trying to decompress? |
Sokarhacd
Posts: 78/1757 |
lunar compress decompresses some of the gfx in certain roms, although I havent had any luck with it...buy you can try if you want, its at fusoya's site. |
Fyxe
Posts: 23/1160 |
Graphics in a ROM to make them viewable in programs like Tile Layer Pro and the like? There is an insane amount of games with compressed graphic files. I have Lunar Compress, but what I have to do to decompress a ROM is completely lost on me (the help files seem to be designed for someone who already has a heap of knowledge about HEX and the like...).
Thanks in advance to anyone who can help. I just need some basics...
EDIT: What, no responses yet? Aren't you people meant to be ROM hackers? >.> |
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hukka
