[FFmpeg-user] Concatenated H.264 or H.265 might not play correctly.drop=#

Luke Davis l1 at newanswertech.com
Wed Jul 23 21:49:34 CEST 2014

On Tue, 22 Jul 2014, Carl Eugen Hoyos wrote:

> Luke Davis <l1 <at> newanswertech.com> writes:
>>>> 1.  What damage is actually happening to my outgoing
>>>> stream here, and is this a problem that can eventually
>>>> disrupt the stream?  I assume it is frames being
>>>> dropped?
> Only you can look at (analyze) the input stream
> and compare the frame count with the output file
> to see if frames are dropped.
> The way I understand the warning (I did not check
> the actual commit) is that frames may be lost.

Any idea _why_ they might be dropped?  I don't think it is a UDP transport 
issue, or I would be seeing timing oddities. It would not appear to be a 
processor or memory issue either, since neither is used nearly to capacity while 
this is going on.
Again, I'm reading separate audio and video streams (AAC, H.264), and mixing 
them into a  segmented mpegts output.

It seems to be a systematic process, dropping about 1 frame every minute or so, 
at least according to the errors.  Over two hours, it does not seem to have a 
pronounced effect on the resulting stream, but over 4-6 hours it might.

If I can figure out why it's happening, maybe there is a buffer size or the like 
I can manipulate to avoid the problem.

I believe it's coming from mov.c, in function mov_skip_multiple_stsd, line 1638. 
But I still haven't figured out what's going on in there.


More information about the ffmpeg-user mailing list