[FFmpeg-devel] [PATCH] avcodec/aac_tablegen: speed up table initialization

wm4 nfxjfg at googlemail.com
Fri Nov 27 13:05:49 CET 2015

On Fri, 27 Nov 2015 06:42:21 -0500
Ganesh Ajjanagadde <gajjanagadde at gmail.com> wrote:

> On Fri, Nov 27, 2015 at 5:35 AM, Rostislav Pehlivanov
> <atomnuker at gmail.com> wrote:
> > LGTM, but could you leave (just comment it out) the old code in there
> > so it's a little easier to follow?  
> >>         //ff_aac_pow2sf_tab[i] = pow(2, (i - POW_SF2_ZERO) / 4.0);
> >>         //ff_aac_pow34sf_tab[i] = pow(ff_aac_pow2sf_tab[i], 3.0/4.0);  
> >
> > The accuracy increase is always nice.  
> Done and pushed. Thanks.
> BTW, do you or others think that the new performance figures are
> sufficient to justify getting rid of config_hardcoded_tables and
> associated ifdefry and C file here?

I think this would be a very good goal. I never understood why there
has to be both, and the complication caused by it is terrible.

I'm not sure if dynamic generation was already the default, but in any
case the init call should be protected with ff_thread_once.

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