[FFmpeg-user] video delay after audio fix

Andrey Utkin andrey.krieger.utkin at gmail.com
Tue Mar 6 10:59:10 CET 2012

2012/3/5 funtastic <officemab at gmail.com>:
> ffmpeg -i rtsp:// -vcodec copy
> -acodec copy -ss 0.0001 -t 30 -y share.mp4

AFAIK -ss without transcoding shows bad precision/accuracy results/
because it seeks to closest key frame. This can result in +/- several
seconds from desired time point. I'd like somebody else to
check/correct me, though.

Regarding root of you problem, bad timestamps from Wowza :) I also
have this sort of problem with RTMP/FLV streams from wowza. I try to
workaround it using video filter
which should not allow non-monotonity of decoded frames pts.
If you feel you understand the problem, and cannot solve it with
ffmpeg utility, you can go deeper and make up an application that uses
ffmpeg API.
Hope this helps.

PS Carl is right, if you use libav.org version, go to list
libav-tools at libav.org , there are people to help, too. To ask for help
here, use ffmpeg.org last version.

Andrey Utkin

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