sound/swp00.cpp: Improved DPCM sample decompression #12300
Merged
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Through reverse engineering the ROMs of the MU50 and related sound modules I think I've figured out that the magic number that the MU50 stores along with the sample format isn't the fractional part of the loop point, but instead holds an offset and scale for DPCM decompression (which I guess makes it ADPCM).
I guess some of the related sound devices (like maybe the SWP30?) cloud also use this patch.