[FFmpeg-trac] #2836(avcodec:new): Lost video frames when decoding h264 stream

FFmpeg trac at avcodec.org
Mon Aug 5 17:06:30 CEST 2013

#2836: Lost video frames when decoding h264 stream
             Reporter:  Marcin       |                     Type:  defect
               Status:  new          |                 Priority:  normal
            Component:  avcodec      |                  Version:  git-
             Keywords:  h264, lost   |  master
  frame                              |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
 Summary of the bug:

 I'm trying to transcode h264 stream (DVB-T). It happens that properties of
 the input stream changes on the fly. Decoder automatically reinitializes
 context "[h264 @ 0xa29fae0] Reinit context to 720x576, pix_fmt: 0", but
 avcodec_decode_video2 starts loosing frames. First it looses significant
 number (around 40) of frames and than repeatedly returns one frame and
 skips three frames.

 Problem is related to the avcodec it can be observed in ffmpeg, ffplay and
 custom applications.

 Full report from ffmpeg and two examples of input (stream copy) are in the

 How to reproduce:
 % ffmpeg -i video_decoder-lost_frames_in_dvbt-example2.ts -acodec mp3
 -vcodec mpeg4  -b 15000000 out2.mp4
 Verified versions: 2.0, master, 1.2
 Built on Ubuntu 12.04

Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/2836>
FFmpeg <http://ffmpeg.org>
FFmpeg issue tracker

More information about the FFmpeg-trac mailing list