Hacking GameCube Shrinking for DiosMios

[papermanzero]

Hi everyone,

I have one question concerning the shrinking of GameCube games (especially due to DiosMios)
There are several discussion about how to shrink, how to parse, how to scrub or how to compress games.
But there is no description about the differences and the best method of "making GameCube games smaller in size".

Every GameCube Game has an iso size of 1,35GB.
Now the question is: What's the best way to reduce the disc data in order to get the real game size.

On the wii it's simple:
The user has the WBFS format which is the real wii game size.
Furthermore the user is able to convert the WBFS format (reduced size) to the original iso size (4,7 GB or 8,4 GB).
So it's possible to switch between the compressed WBFS format and the real iso size without losing information.

But what about on the GameCube?
There are several tools to rip or dump Gamecube images.
The best way to get a clean GameCube image is CleanRip.
To reduce the size there are several tools:
GCMutility, DiscEx, GCReEx, WiiScrubber, FSTFIX...

But all tools are using a different algorithm to reduce the original iso size.
This results in different compressed (iso or gcm) formats.

To make it clear, If you use a MD5 verifier you can create the checksum of the games.
For example Pokemon Colosseum:
If the user shrinks the original CleanRip image (file1) with GCMutility (file2) or DiscEx (file3) you have the same iso size but different checksums.
If we go one step further and use FSTFIX to create the original image again we will get 2 completely new images with 2 new checksums.

A short overview:
file 1: "\original\Pokemon Colosseum.iso" -> 1,459,978,240 bytes -> original MD5 checksum
file 2: "\gcmutility\Pokemon Colosseum.iso" -> 660,794,288 bytes -> MD5 checksum is different to file 3
file 3: "\discex\Pokemon Colosseum.iso" -> 660,794,288 bytes -> MD5 checksum is different to file 2
file 4: "\gcmutility\Pok_fstfix.iso" -> 1,459,978,240 bytes -> MD5 checksum is different to original MD5 and to file 5
file 5: "\discex\Pok_fstfix.iso" -> 1,459,978,240 bytes -> MD5 checksum is different to original MD5 and to file 4

All in all the main question is: why?
I believe most of us would like to reduce GameCube games to the optimal size but don't want to lose important information which may causes problems with for example dios mios.

Is there a way to compress GameCube games to the real game size in an effective way?
Furthermore is it possible to get the original game (size) back without changed data?
Does anybody know a tool which can handle GameCube backups in this way?

 

[Gnarmagon]

I recommend gcit.exe (Gamecube Iso Tool)

Edit: Export ISO as trimmed

 

[Mazamin]

Q: Furthermore is it possible to get the original game (size) back without changed data?
A: If you trim, then you'll lose the garbage, the garbage is random filled, so you can't get the original garbage back once you trim an iso, hence the md5 will be different but the size the same, cause the iso will be filled with 00s or FFs(or maybe random).

 

[driverdis]

Why not use Nintendon't over Dios Mios?

 

[Wuigi]

Once you have trimmed the games you can also use them in nintendont which is significantly better than diosmios in terms of compatibility and it was even developed by the same guy crediar and fix94 and other developers have made an even better application out of it.

 

[spotanjo3]

To me, I prefer to leave it alone in an original size.

 

[driverdis]

To me, I prefer to leave it alone in an original size.

I do this for most games but for really small ones that are a few hundred meg or smaller, I shrink them as it makes zero sense to leave them wasting a gig of space for nothing.

 

[spotanjo3]

I do this for most games but for really small ones that are a few hundred meg or smaller, I shrink them as it makes zero sense to leave them wasting a gig of space for nothing.

I understand. To me, I don't mind.