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OpenMLTD / MLTDTools

Tools for THE iDOLM@STER Million Live! Theater Days (MLTD/MiriShita/ミリシタ) / 偶像大师百万演唱会剧场时光工具箱
BSD 3-Clause Clear License
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HCA decrypt result inconsistent with libcgss #42

Open nulla2011 opened 4 years ago

nulla2011 commented 4 years ago

There's a little bit difference between the wave file extracted by HcaDec.exe in this repository and the wave file extracted by hca2wav.exe in libcgss . I put them in two tracks , invert the phase of one of them and found the differences is mostly above 7kHz frequency.

image

So which one is correct ?

btw , this project's decrypt result is the same with DereTore .

hozuki commented 4 years ago

Yes MLTDTools still uses DereTore's decoder, which is a direct port of the original decoder in C++. libcgss integrated some of Ishotihadus' improvements (see his repo). So... I guess Isho's is correct in high frequency.

nulla2011 commented 4 years ago

OK. I made a comparation. The result of libcgss' latest version is the closest to the CD version. 39. But I found it is almost monaural in high frequency, I dont know why.

hozuki commented 3 years ago

BTW for a mathematically correct encoder/decoder please refer to VGAudio.