[FFmpeg-devel] [PATCH] avutil/mathematics: speed up av_gcd by using Stein's binary GCD algorithm
michael at niedermayer.cc
Sun Oct 11 00:26:35 CEST 2015
On Sun, Oct 11, 2015 at 12:10:39AM +0200, James Darnley wrote:
> On 2015-10-10 23:06, Ganesh Ajjanagadde wrote:
> > ...
> Is the greatest common denominator (yes, I had to look that up) actually
> used anywhere that is slow and needs to be fast?
> All the uses of 'av_gcd' found by grep appear be dealing with timing. I
> see framerate, timebase, scale. I do see uses in rational.c which
> implies uses through AVRational, how many codecs are using rational
> numbers in their processing?
some of the timebase related code does run per packet and some
audio codecs have rather short duration packets so it could be
that in case of such codecs on embeded hw the timebase related
calculations are not as insignificant as one might expect but
I dont know
Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
The real ebay dictionary, page 1
"Used only once" - "Some unspecified defect prevented a second use"
"In good condition" - "Can be repaird by experienced expert"
"As is" - "You wouldnt want it even if you were payed for it, if you knew ..."
-------------- next part --------------
A non-text attachment was scrubbed...
Size: 181 bytes
Desc: Digital signature
More information about the ffmpeg-devel