[FFmpeg-devel] [PATCH 3/3] lavu/rational: add more info regarding floor(x+0.5) usage
Ganesh Ajjanagadde
gajjanag at gmail.com
Thu Feb 25 03:20:11 CET 2016
Add some more verbose info regarding why the imprecise and slow floor(x+0.5) hack
is used; helpful for future maintenance.
Signed-off-by: Ganesh Ajjanagadde <gajjanag at gmail.com>
---
libavutil/rational.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/libavutil/rational.c b/libavutil/rational.c
index 3e841ad..22cf665 100644
--- a/libavutil/rational.c
+++ b/libavutil/rational.c
@@ -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);
--
2.7.1
More information about the ffmpeg-devel
mailing list