[CELT-dev] Inside the psydecay_init function

Osama Fadhil osamaesl at yahoo.com
Fri Apr 22 21:49:55 PDT 2011


Good Morning;

Fo this portion of code in the psydecay_init( ) of CELT (psy.c) :

decayR[i]=Q15ONE*power(0.1f,deriv)   /commented: decay corresponding to -10 
dB/Bark.

decayL[i]=Q15ONE*power(0.0031623f,deriv)   /commented: decay corresponding to 
-25 dB/Bark.


Why 0.1 (or 0.0031623) is being raised to the power of deriv? what is the 
meaning of this? why 0.1(or 0.0031623)  not other number? is it   related to 
(-10, -25 respectively) how we get it?!

Why Q15ONE (which is either 32767 or 1.0f, as I have observed it in the code) is 
being multiplyied by the term also?

Thank you for your attention,

Osama.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.xiph.org/pipermail/opus/attachments/20110422/3f28144c/attachment-0002.htm 


More information about the celt-dev mailing list