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> While folks are thinking about CDs: I've not been able to get an F2/F3-frame CD image. If anyone has such a thing (not copyrighted, just a CD containing a text file or public domain music piece is fine), I'd love to get it so I can implement a CIRC encoder/decoder!

I don't know if you've already seen this, but I've heard of someone getting an image like this. They used it to discover what the AccurateRip drive offset values mean in terms of the physical location of the subchannel data and interleaved main channel data on the disc. There's a vague description of their process in there as well.

https://club.myce.com/t/offsets-handling-syncing-of-audio-da...

> Using my neat hardware setup I now have captured a precious 0.1 seconds worth of 588-bit channel data frames from a pristine audio CD, each frame containing, among other things, a subchannel byte and 24 bytes of audio data.

> I can reproduce the CIRC, get the de-interleaved audio data, and also do the Reed-Solomon C1/C2 stuff in software from my analog laser readouts - showing an error-free read, identical to what I get with my Plextor using somewhat more conventional methods.



That is exactly what I need, but unfortunately the post is from 2004, and he didn't link to that precious sample of data =(

Still, some very interesting info there. It looks like if and when I get this data, I may need a follow-up article that goes even deeper.


Hmm, poking around on that website, there's some more:

https://club.myce.com/t/announcing-laser2wav-a-software-only...

That tarball seems to have fallen off the internet, but there's also this. Check out laserbits.txt. I wonder if that's the data.

https://github.com/sidneycadot/Laser2Wav/tree/master/python




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