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randygordon / rdac

RDAC decoding
GNU Lesser General Public License v3.0
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Documentation of RDAC format/algorithm? #4

Open markaudacity opened 1 year ago

markaudacity commented 1 year ago

Do you have notes/documentation of the RDAC algorithm separate from the code itself? My DSP knowledge isn't good enough to parse the structure from just reading the code.

Thanks for the effort you must have put into the original code, and for sharing it on Github.

randygordon commented 1 year ago

Sorry, the code is all I have. At the time I was reverse engineering it and introducing prototypes to the community there was some discussion at http://www.vsplanet.com/ubbthreads/ubbthreads.php. You might find some historical information there. You can read the Roland patents, though they are quite vague. They do give an idea of the general principle involved in the encoding. I wouldn't consider is DSP, but more of a compression algorithm.

On Sat, Dec 17, 2022 at 2:38 PM markaudacity @.***> wrote:

Do you have notes/documentation of the RDAC algorithm separate from the code itself? My DSP knowledge isn't good enough to parse the structure from just reading the code.

Thanks for the effort you must have put into the original code, and for sharing it on Github.

— Reply to this email directly, view it on GitHub https://github.com/randygordon/rdac/issues/4, or unsubscribe https://github.com/notifications/unsubscribe-auth/AG6ID3KYL6BZL4I6V3R5E73WNY6H3ANCNFSM6AAAAAATCFP2DA . You are receiving this because you are subscribed to this thread.Message ID: @.***>

markaudacity commented 1 year ago

Thanks for the quick response.

I appreciate your efforts nonetheless, and I’ll take a look at the patent documents to see if I can glean anything there.

If you don’t mind my asking, what was the process you used to figure out the format and the decoding? I’m working on trying to decode card backups from the Boss SP-202, which I understand to store RDAC-coded wave data, and I can use any help or ideas I can get!

Thanks much, mark

randygordon commented 1 year ago

A good hex editor and a lot of deep concentration. You will figure it out!

On Sun, Dec 18, 2022 at 8:35 AM markaudacity @.***> wrote:

Thanks for the quick response.

I appreciate your efforts nonetheless, and I’ll take a look at the patent documents to see if I can glean anything there.

If you don’t mind my asking, what was the process you used to figure out the format and the decoding? I’m working on trying to decode card backups from the Boss SP-202, which I understand to store RDAC-coded wave data, and I can use any help or ideas I can get!

Thanks much, mark

— Reply to this email directly, view it on GitHub https://github.com/randygordon/rdac/issues/4#issuecomment-1356833100, or unsubscribe https://github.com/notifications/unsubscribe-auth/AG6ID3INJY3SH4YMBEZUSRLWN44OBANCNFSM6AAAAAATCFP2DA . You are receiving this because you commented.Message ID: @.***>

samuel-attaya commented 10 months ago

@markaudacity did you even happen to make any progress with decoding the SP202 backups? I came across https://www.reddit.com/r/32kHz/comments/znnz5b/imaged_the_smartmedia_card_from_my_sp202_this_is/ which looks to have someone going through it with a hex editor but it looks like that account isn't active on reddit so I can't ask how far they got.