[Libav-user] Erratic encoding issue: Crazy framerates.

Robert Krüger krueger at lesspain.de
Thu Sep 3 17:29:35 CEST 2015

On Thu, Sep 3, 2015 at 10:23 AM, Talgorn François-Xavier <
fxtalgorn-at-yahoo.fr at ffmpeg.org> wrote:

> Hi all,
> Thank you in advance for your help.
> I wrote a program that takes videos as input (H264), process filters on it
> and encode a modified video in MP4 (simple profile).
> Everything works fine but the fact that some videos are encoded with crazy
> frame rates, like 2500 or 24000 fps.
> I assume the problem is related to the way I manage timestamps. I tried
> tens of workarounds to no avail.
> Here is the resulting infos of both an example that fails and another that
> is OK.
If I were you I would start by checking the timestamps and timebases of the
encoded files that cause trouble by running ffprobe on them and output
stream timebases and packet timestamps to see what's actually in them
that's screwing up the fps. maybe you just used an incorrect timebase or
something like that. One thing that many people overlook is to check
whether your muxer has changed the time base after initialization. you have
to deal with that case (and rescale your packet timestamps to that new
timebase) and the mov/mp4 muxer does that under certain circumstances.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://ffmpeg.org/pipermail/libav-user/attachments/20150903/cee4c752/attachment.html>

More information about the Libav-user mailing list