opus - May 2011 - Codebook table

Hello,

There is a coodebook for the pitch gains stored in pgain_table.h. How can we get
such a table? I have read in the CELT's paper that the codebook is trained,
but
I do not understand what that realy means. Can anyone give me an idea about 
that? 


Thank you very much.
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> There is a coodebook for the pitch gains stored in pgain_table.h. How
> can we get such a table? I have read in the CELT's paper that the
> codebook is trained, but I do not understand what that realy means. Can
> anyone give me an idea about that?
I don't know what approach Jean-Marc used, but most likely something 
simple and straightforward like Lloyd's algorithm:
http://en.wikipedia.org/wiki/Lloyd's_algorithm
or LBG: http://en.wikipedia.org/wiki/Linde?Buzo?Gray_algorithm

However, CELT no longer uses the pitch predictor described in that 
paper, and thus no longer requires its trained codebooks.