[FFmpeg-user] Problems getting the very last frames of videos using av_read_frame

Peter Rennert p.rennert at cs.ucl.ac.uk
Thu Oct 30 14:48:20 CET 2014

Hi Moritz,

Thanks for looking into this.

On 30/10/14 13:40, Moritz Barsnick wrote:
> On Thu, Oct 30, 2014 at 12:15:34 +0000, Peter Rennert wrote:
>> except for the last frames. It seems as av_read_frame only reads until
>> the last key frame and does not go beyond it.
> Do you ever see "Unable to decode video picture: %d" from
> https://bitbucket.org/groakat/ffvideo/src/b45143f755ac8da1e6ed4f52a11217af1e093d54/ffvideo/ffvideo.pyx?at=default#cl-233
> ???
No, I never saw that Error being raised.

> There's an example in ffmpeg's doc/ directory, named
> demuxing_decoding.c, which uses your described av_read_frame() loop,
> and succeeds at reading all 1000 frames.
Thanks for that lead. I will follow that up and report the results later.

> So the issue is probably somewhere in the python wrapper.
>> ffmpeg version 2.2.git Copyright (c) 2000-2014 the FFmpeg developers
>>     built on Apr  9 2014 16:32:16 with gcc 4.8 (Ubuntu/Linaro 4.8.1-10ubuntu9)
> This is quite a bit too old to gain support on this list. :)
I will rebuild ffmpeg, and see if it persists.

>>     WARNING: library configuration mismatch
> and is apparently using libraries from a different build, which is not
> a good idea.
> The first suggestion would be to build lastest git, and ensure you're
> not using "stale" libraries from older installs.
> (I don't have enough knowledge to tell you more about how to use libav
> properly, I only know the examples. Anyway, there's a separate list for
> libav issues: https://ffmpeg.org/mailman/listinfo/libav-user )
To my knowledge I am not using libav. At least when I last checked ;).

> Moritz
> _______________________________________________
> ffmpeg-user mailing list
> ffmpeg-user at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-user

More information about the ffmpeg-user mailing list