lavu/rational: add more info regarding floor(x+0.5) usage

Add some more verbose info regarding why the imprecise and slow floor(x+0.5) hack
is used; helpful for future maintenance.

Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Ganesh Ajjanagadde <gajjanag@gmail.com>
This commit is contained in:
Ganesh Ajjanagadde 2016-02-24 20:47:00 -05:00
parent 380fd32a8c
commit 7dabc78ce1

View File

@ -115,7 +115,8 @@ AVRational av_d2q(double d, int max)
frexp(d, &exponent);
exponent = FFMAX(exponent-1, 0);
den = 1LL << (61 - exponent);
// (int64_t)rint() and llrint() do not work with gcc on ia64 and sparc64
// (int64_t)rint() and llrint() do not work with gcc on ia64 and sparc64,
// see Ticket2713 for affected gcc/glibc versions
av_reduce(&a.num, &a.den, floor(d * den + 0.5), den, max);
if ((!a.num || !a.den) && d && max>0 && max<INT_MAX)
av_reduce(&a.num, &a.den, floor(d * den + 0.5), den, INT_MAX);