Thank you, and yes I do plan to do more/longer C64 cracking tutorials when I get time… although I was hoping someone far more qualified would step in and do some 😛
I have a couple of my cracks documented, for example Turbo Outrun (cyan loader), Project Stealth Fighter (custom DOS) and Katakis.
I use code injection on the auto-boot and execute my own code to decrypt and save all parts automatic. But most of these tutorials are not complete as i never intended to release them. 🙂
It’s good people still make these tutorials for preservation!
If you wanted to complete your tutorials, I’m sure Flashtro would be very grateful 🙂 Anything from someone who was on C64 “back in the day” is most welcome – my only contribution was helping RSI with phonecalls in 1993+, which doesn’t really count 🙂
Especially anything on disk-cracking, so far I’ve only tackled tape loaders.
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5 years ago
“XAKK”, we said.
“Never heard of it”, the guy replied.
“You will”, we said and tried to look cool.
RLE packing was a mistake; you will get much better compression if you crunch directly with the Cruel cruncher (I’m partial to Cruel cruncher 2.5+ from Galleon of Oneway). And if you think about it, it’s logical: a RLE compressed file has a lot less similar bytes to compress, in fact it will be close to a random file, with little to no repeating bytes. So if you want the smallest possible file: 1. link the uncompressed intro to the three files (use XAKK’s Cross linker, it really is the best: https://csdb.dk/release/?id=176544) 2. crunch with the Cruel cruncher. I spent… Read more »
They didn’t quite think it through… I think. There is one transformation you can do before crunching that will actually increase the compression ratio (wasn’t invented back in the day yet), I’ve been trying to remember what it is for the past month to no avail… But I do remember the algorithm is explained on Wikipedia and I think LZMA uses it before compressing data…
Ah, sweet teenage memories! 🙂 I was a proud member of XAKK and a quite productive cracker for a few years during the late eighties.
I always adored your demos my friend. There always were a quality sticker to those XAKK productions.
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Fixed
Thank you WK! Will check it for sure. Hope you’ll do more C64 and also for some other platforms (GBC? DC? 🙂 You have so much to share! 🙂
Very nice tutorial.
I hope you will do some more!
Thank you, and yes I do plan to do more/longer C64 cracking tutorials when I get time… although I was hoping someone far more qualified would step in and do some 😛
I have a couple of my cracks documented, for example Turbo Outrun (cyan loader), Project Stealth Fighter (custom DOS) and Katakis.
I use code injection on the auto-boot and execute my own code to decrypt and save all parts automatic. But most of these tutorials are not complete as i never intended to release them. 🙂
It’s good people still make these tutorials for preservation!
If you wanted to complete your tutorials, I’m sure Flashtro would be very grateful 🙂 Anything from someone who was on C64 “back in the day” is most welcome – my only contribution was helping RSI with phonecalls in 1993+, which doesn’t really count 🙂
Especially anything on disk-cracking, so far I’ve only tackled tape loaders.
“XAKK”, we said.
“Never heard of it”, the guy replied.
“You will”, we said and tried to look cool.
https://www.c64-hof.com/groups/x/xakk/history.htm
RLE packing was a mistake; you will get much better compression if you crunch directly with the Cruel cruncher (I’m partial to Cruel cruncher 2.5+ from Galleon of Oneway). And if you think about it, it’s logical: a RLE compressed file has a lot less similar bytes to compress, in fact it will be close to a random file, with little to no repeating bytes. So if you want the smallest possible file: 1. link the uncompressed intro to the three files (use XAKK’s Cross linker, it really is the best: https://csdb.dk/release/?id=176544) 2. crunch with the Cruel cruncher. I spent… Read more »
It does seem logical, but if you look at 90% of c64 cracks you’ll see they’re ‘char-packed’ first then crunched. I was just following tradition! 😛
They didn’t quite think it through… I think. There is one transformation you can do before crunching that will actually increase the compression ratio (wasn’t invented back in the day yet), I’ve been trying to remember what it is for the past month to no avail… But I do remember the algorithm is explained on Wikipedia and I think LZMA uses it before compressing data…
Found it! You can apply a Burrows-Wheeler transformation to the data before crunching:
https://en.wikipedia.org/wiki/Burrows%E2%80%93Wheeler_transform
Thanks, and thanks for the Xakk cross-linker recommendation too 😛 I’ll use it in future.
Oh you are very welcome. Glad I could be useful.
Thanks for this tutorial, I always like to read this type of thing!! 😉
Thanks for this 🙂
Always nice to get a new tutorial.
Very nice, I am going to read this 🙂
SYS 64738
hit me up! Also, WK 😛