On 2 March 2016 at 04:04, Ganesh Ajjanagadde <gajja...@gmail.com> wrote:
> On Tue, Mar 1, 2016 at 7:52 AM, Derek Buitenhuis > <derek.buitenh...@gmail.com> wrote: > > On 3/1/2016 3:21 AM, Ganesh Ajjanagadde wrote: > > > > [...] > > > >> --- > >> libavcodec/aacenc_utils.h | 3 +-- > >> 1 file changed, 1 insertion(+), 2 deletions(-) > > > > Cool. Looks like an obvious/easy win, assuming it's identical. > > They are not precisely identical, and in fact the change results in > slightly better accuracy wrt the mathematical expression, simply > because sqrtf(q * sqrtf(q)) is not always a correctly rounded float. I > vaguely recall negligible ~ 2/3 ulp differences. The table is > correctly rounded; I tested that while speeding up the tablegen. > > Added a small line to this effect in the notes. > > I did test it for a few test tracks and the results had the exact same SHA1 as before. Either the differences are only affecting in very extreme cases or we've cracked SHA1. _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
