Speex dev - Feb 2010 - Fwd: Re: Fixed Point on wideband-mode: Single Frame loss on 2000 Hz sine causes "freak off"

Hi Jean-Marc,

dBFS means dB relative to digital full scale. In other words: a sine value of
-42 dBFS will, on a 16 bit PCM signal, swing between 131 and -131 only (16384 *
10^(-42/20))
So we are far below +/-8000.

At the moment, I'm out of ideas how to debug systematically. That even very
small rounding errors alter pitch values fundamentally makes the situation worse
for me, because it means that the huge differences in pitch between fixed and
floating point are not neccessary part of the problem.
Do you have some tips for me how to proceed?

cheers,
Frank
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Quoting Frank Lorenz <Frank_wtal at web.de>:

Can you look at the residual signal? i.e. what it looks like after the pitch is
removed. Any significant difference there? Also, the pitch gain can be
informative.

    Jean-Marc
> Hi Jean-Marc,
>
> dBFS means dB relative to digital full scale. In other words: a sine value
of
> -42 dBFS will, on a 16 bit PCM signal, swing between 131 and -131 only
(16384
> * 10^(-42/20))
> So we are far below +/-8000.
>
> At the moment, I'm out of ideas how to debug systematically. That even
very
> small rounding errors alter pitch values fundamentally makes the situation
> worse for me, because it means that the huge differences in pitch between
> fixed and floating point are not neccessary part of the problem.
> Do you have some tips for me how to proceed?
>
> cheers,
> Frank
> ______________________________________________________
> GRATIS f?r alle WEB.DE-Nutzer: Die maxdome Movie-FLAT!
> Jetzt freischalten unter http://movieflat.web.de
>
>
>