[FFmpeg-devel] [PATCH] Common ACELP code & G.729 [6/7] - G.729 postfilter

Vladimir Voroshilov voroshil
Wed May 14 04:39:00 CEST 2008


Michael Niedermayer wrote: 
> On Wed, May 14, 2008 at 12:25:24AM +0700, Vladimir Voroshilov wrote:
> > 2008/5/12 Michael Niedermayer <michaelni at gmx.at>:
> > >

[...]

> > +                /*
> > +                  Compute numerator of pseudo-normalized correlation R'(k)
> > +                  (4.2.1, Equation 81)
> > +                */
> 
> > +                sum = 0;
> > +                for(n=0; n<subframe_size; n++)
> > +                    sum += delayed_signal[k][n+i] * sig_scaled[n + RES_PREV_DATA_SIZE];
> 
> duplicate of sum_of_squares()

Hm. where ?

delayed_signal[k] has fractional offset (k+1)/8,
sum_of_squares can't be used here (it is applicapable
to integer offsets only).

[...]

> > +        /*
> > +          Compute R'(k) correlation's numerator
> > +        */
> 
> > +        sum = 0;
> > +        for(n=0; n<subframe_size; n++)
> > +            sum += residual_filt[n] * sig_scaled[n + RES_PREV_DATA_SIZE];
> 
> duplicate of sum_of_squares()

Hm. same as above: residual_filt has fractional offset

 
-- 
Regards,
Vladimir Voroshilov mailto:voroshil at gmail.com
Omsk State University
JID: voroshil at jabber.ru
ICQ: 95587719




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