flipnote-collective / kwz-parser Goto Github PK

We still haven't quite nailed the KWZ audio section. It seems to be very similar to the audio format used in Flipnote Studio for DSi -- monochannel ADPCM with nibbles flipped, just sampled at 16364Hz. However, the output sounds much worse than what can be heard in the app and includes random bursts of static. You can try this for yourself using kwzAudio.py.

I'm pretty sure we're on the right track, since tables needed for ADPCM decoding can be found in the app's binary:

(light blue shows index tables while dark blue and purple are step tables)

Nintendo is probably doing something a little weird here, though :/ We'd appreciate any help we can get.

When running kwzAudio.py, it errors out when it reaches line 252 of kwz.py with the error: UnicodeDecodeError: 'utf-8' codec can't decode byte 0xdc in position 0: invalid continuation byte. This can be remedied by removing .decode("utf-8") on line 250 of kwz.py.

Command run was kwzAudio.py cmz2mklg0c1zqcceks5wrmbp5ien.kwz 0 outputAudio.wav

Looks like the latest commit 5196b6f removed the ins from a bunch of for a in range constructs, thus ending up as invalid syntax.

This means that no one has ever tested or even used this code in a few months, since that syntax error would have been resolved already if so. Until today, where someone linked this code in a Discord server I'm in because they were trying to use it.