[FFmpeg-cvslog] lavf: fix multiplication overflow in avformat_find_stream_info()

[Mans Rullgard]

ffmpeg | branch: release/0.8 | Mans Rullgard <mans at mansr.com> | Tue Nov 15 22:33:49 2011 +0000| [d6f763659c6115e91d2fa981faffdb041d93f7a4] | committer: Anton Khirnov

lavf: fix multiplication overflow in avformat_find_stream_info()

Converting to double before the multiplication rather than after
avoids an integer overflow in some cases.

Signed-off-by: Mans Rullgard <mans at mansr.com>
(cherry picked from commit 52767d891c665ab1124fe4ce82d99b59673de7d2)

Signed-off-by: Anton Khirnov <anton at khirnov.net>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=d6f763659c6115e91d2fa981faffdb041d93f7a4
---

 libavformat/utils.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/libavformat/utils.c b/libavformat/utils.c
index d155599..aa3ca59 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -2368,7 +2368,7 @@ int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options)
                 for (i=1; i<FF_ARRAY_ELEMS(st->info->duration_error); i++) {
                     int framerate= get_std_framerate(i);
                     int ticks= lrintf(dur*framerate/(1001*12));
-                    double error= dur - ticks*1001*12/(double)framerate;
+                    double error = dur - (double)ticks*1001*12 / framerate;
                     st->info->duration_error[i] += error*error;
                 }
                 st->info->duration_count++;