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Re:Sega Saturn CD – Cracked after 20 years (2016) [video] by jaywalk on Thursday June 16, 2022 @10:02AM (#31766153)
Part of the copy protection includes physical features of the disc that must be pressed into it when it's produced, meaning a BluRay writer has no way of replicating it.
Re:Sega Saturn CD – Cracked after 20 years (2016) [video] by dundarious on Thursday June 16, 2022 @11:23AM (#31767137)
My understanding is that the PS1 copy protection encoded the first pits and peaks in a way that a normal CD drive’s error correction logic would tolerate, but in such a way that the special firmware on the PS1 could detect the profile of the “errors” and ensure they matched expectations.

Consumer CD Burners didn’t have firmware (or maybe even the physical capability) to reproduce these “errors”.

Imagine a vinyl record where the start of the track has a groove that isn’t perfectly tracing the perimeter, but is actually a low amplitude sine wave of a certain frequency, waving in to the center and out to the perimeter. Any record player could trace the groove correctly, despite the fact that there is a low amplitude sine wave, and you’d hear the audio correctly (error correction). But a special record player could even detect the sine wave and reject records that don’t have it. I’m hand-waving away the fact that you’d get a little bit of wow and flutter from the sine wave, but you get the idea.

Re:Sega Saturn CD – Cracked after 20 years (2016) [video] by rasz on Thursday June 16, 2022 @09:26PM (#31773044)
https://en.wikipedia.org/wiki/Wobble_frequency

Afaik Wobble is pre molded in polycarbonate layer and cant be altered by CD Writer no matter the firmware.

https://en.wikipedia.org/wiki/Absolute_Time_in_Pregroove

Re:Sega Saturn CD – Cracked after 20 years (2016) [video] by Thoreandan on Thursday June 16, 2022 @01:40PM (#31768813)
Excellent analogy. You could, if you had a full CD pressing & mastering plant, copy those discs with "wobble groove" and all. But it's a clever clever side channel. https://archive.ph/LuPaY#:~:text=they%20track%20the%20%27-,w...
Re:Sega Saturn CD – Cracked after 20 years (2016) [video] by eatbitseveryday on Thursday June 16, 2022 @02:20PM (#31769248)
Awesome, I learned a lot in this thread. Thank you (plural) for the answers and your time to reply to my question!
Re:Sega Saturn CD – Cracked after 20 years (2016) [video] by bombcar on Thursday June 16, 2022 @10:24AM (#31766413)
This is usually what they add, though the Nintendo Gamecube used a DVD-similar format at a different size to make it harder to copy. They also ran at CAV (constant angular velocity) instead of constant linear velocity (CLV) which lead to the rumor that they "spin backwards".