Author Topic: Set Sprucing  (Read 2918 times)

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Offline Zandro

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Re: Set Sprucing
« Reply #15 on: June 16, 2017 - 07:09:10 »
Nope, it does not match the hash I specified.  It wasn't whether GoodGBA accepts it, it's HOW it's accepted.

Offline yeahimdukenukem

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Re: Set Sprucing
« Reply #16 on: June 16, 2017 - 08:35:44 »
Doesn't it use SHA-1 per default?
And why is it accepted when it doesn't match?

Offline Zandro

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Re: Set Sprucing
« Reply #17 on: June 16, 2017 - 15:30:00 »
I heard Good insight and found CUE's bag of packers.  The ROM is LZSS encoded.  Decoding gives the correct hash.
« Last Edit: June 16, 2017 - 15:31:36 by Zandro »

Offline yeahimdukenukem

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Re: Set Sprucing
« Reply #18 on: June 16, 2017 - 16:08:38 »
I've just tested GoodSNES with both Dennis ROMs.
I see that they have different CRCs, but both are accepted as the same ROM by GoodSNES.
I still don't understand that. A binary diff of the ROMs is showing large parts that are equal, but obviously not everything. The size is the same, too.
Both do not run in emulators. They say bad checksum, but are listing C88748DB as the 'correct'(?) checkum for both ROMs. ZSNES tells me to deinterleave the ROMs.
So what's going on here? Please help me understand that.

Offline yeahimdukenukem

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Re: Set Sprucing
« Reply #19 on: June 26, 2017 - 15:17:19 »
Hi Zandro,

I have read and tested even more, but I still don't fully understand.
I now see that the GoodTools do some magic to match the files even if they don't 'perfect' match with CRC or SHA-1.
How can I find out which ROMs are matching 'directly' or how did you do that? Is there any way to get the hashes out of GoodTools?

Many TIA for teaching me :)

Offline Zandro

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Re: Set Sprucing
« Reply #20 on: June 26, 2017 - 18:26:07 »
Your realizations were my own 5 years ago, and my findings are what I made this topic for.  The first post already mentions the common steps, the problems of trying to go further, and that I will not expose the hashes out of respect of the given license.  The GoodTools alleviates the need to learn about a bunch of formats (though they're basically the same). The average user can just use the tools without having to get messy with the roms.  For anyone else, it's about asking the right questions.

By the way, I still could not determine the matching properties for the Dennis rom.  That's why I asked here.
« Last Edit: June 26, 2017 - 18:36:03 by Zandro »