[FFmpeg-devel] av_ctz optimization

Ronald S. Bultje rsbultje at gmail.com
Sun Oct 11 13:01:54 CEST 2015


Hi,

On Sat, Oct 10, 2015 at 10:50 PM, James Almer <jamrial at gmail.com> wrote:

> On 10/10/2015 11:44 PM, Ganesh Ajjanagadde wrote:
> > Hi all,
> >
> > Turns out that the De-Bruijn method can be used to speed up av_ctz as
> > well. But before going about it, I was curious as to why such an
> > interface is actually public. It makes absolutely zero sense to me:
> > usage is limited exactly to one location, namely libavcodec/flacenc.c.
> > Was this an accident?
> >
> > Regards,
> > Ganesh
>
> It's not really public since intmath.h is not an installed header.
> Why it exists and is used instead of ff_ctz, i don't know.


Looks like it was added for use in flacenc, and we typically don't share
ff_ symbols between libraries. However, since it's inlined anyway, I'm not
sure anyone cares. Maybe time to remove it?

Ronald


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