[Vorbis-dev] vorbis and MP3 window function

[hkato]

<20040704144224.3c07a8f6.hkato at beige.ocn.ne.jp>
Message-ID: <20040717111623.46374b0d.hkato at beige.ocn.ne.jp>

Dear,

I have a basic question why vorbis window function is different
from MP3's,which is more complex than MP3's.

Because MDCT guarantees perfect reconstruction with any window function
if the window functions satisfy the relations.

h(x):MDCT window function
f(x):Inverse MDCT window function
f(x)=h(x)
h(K-1-x)=h(x)
f(r+K/2)^2+f(r)^2=2


If does anyone know the reason,please teach me.


P.S.
I made MDCT calculatin Excel sheet (although only 32point).
I hope it will be good to confirm MDCT.

Check
http://www9.ocn.ne.jp/%7Ehkato111/math7/node1.html


hkato