SFX ripping/decoding/dumping features?

[iteachvader]

(06-18-2015, 05:59 AM)jackoalan Wrote: I'd be happy to share any knowledge I can on GameCube audio. I've recently put together a GC-DSPADPCM decoder and encoder that actually works pretty well in multiple games.

https://github.com/jackoalan/audacity/releases

To demystify the DSP format somewhat, it's a proprietary flavor of ADPCM; Each sample is iteratively "predicted" based on the last 2 samples and a set of 8 coefficient pairs (which appear as 16x 16-bit values, or 32-bytes in the file header). The encoder bears the brunt of the complexity, using a discrete-fourier-transform to analyze the audio in the frequency-domain; selecting coefficients with the least error.

If the game in question truly uses MusyX, the SFX are likely bundled in resources known as "sound groups". Metroid Prime 1 and 2 both use MusyX and sound groups for the vast majority of SFX. MrSinistar from M2K2 and myself have reverse-engineered the majority of the sound group format (designated "AGSC" by Retro).

http://www.metroid2002.com/retromodding/wiki/AGSC_(File_Format)

In particular, check out the Pool, Proj, Sample, and SampleDirectory sections. These are the 4 main "chunks" of a MusyX sound group. Different games may arrange them in different orders (in fact, MP1/2 swapped locations of Sample and SampleDirectory), but if you can identify the signature layout of MusyX in a hex-editor, i may be able to modify my "AGSC Extract" tool to help out.

https://github.com/jackoalan/agsc_extract

The game does indeed use the MusyX sound system, but I have no idea how to go about identifying the layout of MusyX in a hex editor. I've used many a hex editor in the past, but never really understood it.

I have the original .DAT files from Rogue Squadron II and III, and was able to extract the one section from each that contains just the sound effects. Is it possible I could supply you with the files while I figure out how to use a hex editor with them? I would appreciate some more advanced assistance; I are dumb.

If I'm supplied with a decoder that can decode all of Rogue Squadron II and III's audio into one big stream, I'll be set. I'll do all the tedious work of isolating each one by hand. I tested the built-in decoder in your Audacity build with Rogue Squadron II's audio, and it still gave me largely garbled audio. However, it was able to decode Namco Museum's music perfectly.