[FFmpeg-devel] [PATCH v2 1/8] aacpsy: use a different metric for the spread of a band

[Michael Niedermayer]

On Thu, Jul 02, 2015 at 11:56:15PM -0300, Claudio Freire wrote:
> On Thu, Jul 2, 2015 at 3:13 PM, Rostislav Pehlivanov
> <atomnuker at gmail.com> wrote:
> > This commit modifies 02dbed6 to use band->active_lines to better gauge how much information is contained within a single band and thus allow the perceptual noise subsitution to more accurately determine which bands to code as noise. The spread[w+g] used before this patch behaved more like a low-pass filter for PNS band_types, which could mistakingly mark some low frequency bands as noise.
> >
> > Reviewed-by: Claudio Freire <klaussfreire at gmail.com>
> > ---
> >  libavcodec/aacpsy.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/libavcodec/aacpsy.c b/libavcodec/aacpsy.c
> > index 78232d4..b16f6b9 100644
> > --- a/libavcodec/aacpsy.c
> > +++ b/libavcodec/aacpsy.c
> > @@ -787,7 +787,7 @@ static void psy_3gpp_analyze_channel(FFPsyContext *ctx, int channel,
> >
> >              psy_band->threshold = band->thr;
> >              psy_band->energy    = band->energy;
> > -            psy_band->spread    = spread_en[w+g];
> > +            psy_band->spread    = band->active_lines * 2.0f / band_sizes[g];
> >          }
> >      }
> 
> 
> Can't say much since I proposed it myself, so... LGTM ;-)

applied

thanks

[...]
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Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

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