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What's the meaning of the binomial coefficients in G.723.1 LPC analysis?

Started by Yidan Zhou October 27, 2002
Hi all,
Now I am reading the standard documents and reference source code
of G.723.1. There is an extra windowing multiplication in between the
Levinson-Durbin recursion and autocorrelation coefficient
calculation. But I do not know why this extra step is necessary.
Could anybody give me clue?
Thanks in advance!

Best regards,

Yidan Zhou



Now I know the answer to it.
This extra windowing is called 'Lag windowing'. Its purpose is to
smooth the short-term spectral envolope when the pitch is shorter
than one frame.
Yidan Zhou
--- In , "Yidan Zhou" <yidanzhou@y...>
wrote:
> Hi all,
> Now I am reading the standard documents and reference source code
> of G.723.1. There is an extra windowing multiplication in between
the
> Levinson-Durbin recursion and autocorrelation coefficient
> calculation. But I do not know why this extra step is necessary.
> Could anybody give me clue?
> Thanks in advance!
>
> Best regards,
>
> Yidan Zhou