Guide: Extracting And Recompiling CDI Images

Moderator: VasiliyRS

Posts: 30

Re: Guide: Extracting And Recompiling CDI Images

Post#131 » Sat Nov 03, 2018 9:32 pm

Thank you for replying. I am going to read the instruction. I hope it works.

Posts: 30

Re: Guide: Extracting And Recompiling CDI Images

Post#132 » Sun Nov 11, 2018 3:41 pm

DR TEAMCAST wrote:@zombie this isn't a guide for Creating a CDI from scratch, there's a lot of extra steps involved like finding LBA specific hex values in the binary (primitive copy protections), downsampling dreamcast specific formats like ADX audio or SFD video, etc

this is a guide for extracting a working pre-made CDI image for the purpose of modding or research

if you want to make a CDI from scratch, refer to this guide, its how i learned all this

LBA 45000 is the standard LBA from almost all retail GD-ROMs

Hi, I don't mean to bump this thread. I want to ask you a question. Should I just skip step 12? He or she doesn't say which files should I drag to newfile.exe or dummy.exe and where does "subtract that number from 684647810" come from.


Before step 12, he or she mentioned this line "cd e4 436a needs to be changed to 0900 0900 and 1032 0d8b needs to be changed to 0800 0d8b. Both of these last two should only occur once...if for some reason they pop up more than once, you have something else going on and it's something i quite frankly haven't encountered."

I looked for cd e4 436a and 1032 0d8b in 1st_read.bin via hex editor. I use wxhex editor. It said that hex codes can't be found. Should I skip that too? I won't mind making a new thread if you believe the questions are off topic. Thank you.

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Re: Guide: Extracting And Recompiling CDI Images

Post#133 » Mon Nov 12, 2018 1:23 pm

those hex codes are for changing the LBA to a new LBA. there can be other copy protections too

you don't really need a dummy file, its just padding. dummy files are only useful if you really know what you're doing and place them in various parts of the CD to speed up load times based on files that are accessed more frequently

yeah making a new thread and being specific about what game you're doing would help
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